2054 lines
80 KiB
Java
2054 lines
80 KiB
Java
/*
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* Copyright (c) 1994, 2021, Oracle and/or its affiliates. All rights reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation. Oracle designates this
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* particular file as subject to the "Classpath" exception as provided
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* by Oracle in the LICENSE file that accompanied this code.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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* or visit www.oracle.com if you need additional information or have any
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* questions.
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*/
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package java.lang;
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import java.lang.annotation.Native;
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import java.lang.invoke.MethodHandles;
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import java.lang.constant.Constable;
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import java.lang.constant.ConstantDesc;
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import java.util.Optional;
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import java.math.*;
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import java.util.Objects;
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// Android-removed: CDS is not used on Android.
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// import jdk.internal.misc.CDS;
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import jdk.internal.vm.annotation.IntrinsicCandidate;
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/**
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* The {@code Long} class wraps a value of the primitive type {@code
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* long} in an object. An object of type {@code Long} contains a
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* single field whose type is {@code long}.
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*
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* <p> In addition, this class provides several methods for converting
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* a {@code long} to a {@code String} and a {@code String} to a {@code
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* long}, as well as other constants and methods useful when dealing
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* with a {@code long}.
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*
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* <!-- Android-removed: paragraph on ValueBased
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* <p>This is a <a href="{@docRoot}/java.base/java/lang/doc-files/ValueBased.html">value-based</a>
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* class; programmers should treat instances that are
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* {@linkplain #equals(Object) equal} as interchangeable and should not
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* use instances for synchronization, or unpredictable behavior may
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* occur. For example, in a future release, synchronization may fail.
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* -->
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*
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* <p>Implementation note: The implementations of the "bit twiddling"
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* methods (such as {@link #highestOneBit(long) highestOneBit} and
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* {@link #numberOfTrailingZeros(long) numberOfTrailingZeros}) are
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* based on material from Henry S. Warren, Jr.'s <i>Hacker's
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* Delight</i>, (Addison Wesley, 2002).
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*
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* @author Lee Boynton
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* @author Arthur van Hoff
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* @author Josh Bloch
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* @author Joseph D. Darcy
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* @since 1.0
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*/
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@jdk.internal.ValueBased
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public final class Long extends Number
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implements Comparable<Long>, Constable, ConstantDesc {
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/**
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* A constant holding the minimum value a {@code long} can
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* have, -2<sup>63</sup>.
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*/
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@Native public static final long MIN_VALUE = 0x8000000000000000L;
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/**
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* A constant holding the maximum value a {@code long} can
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* have, 2<sup>63</sup>-1.
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*/
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@Native public static final long MAX_VALUE = 0x7fffffffffffffffL;
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/**
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* The {@code Class} instance representing the primitive type
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* {@code long}.
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*
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* @since 1.1
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*/
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@SuppressWarnings("unchecked")
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public static final Class<Long> TYPE = (Class<Long>) Class.getPrimitiveClass("long");
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/**
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* Returns a string representation of the first argument in the
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* radix specified by the second argument.
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*
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* <p>If the radix is smaller than {@code Character.MIN_RADIX}
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* or larger than {@code Character.MAX_RADIX}, then the radix
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* {@code 10} is used instead.
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*
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* <p>If the first argument is negative, the first element of the
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* result is the ASCII minus sign {@code '-'}
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* ({@code '\u005Cu002d'}). If the first argument is not
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* negative, no sign character appears in the result.
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*
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* <p>The remaining characters of the result represent the magnitude
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* of the first argument. If the magnitude is zero, it is
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* represented by a single zero character {@code '0'}
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* ({@code '\u005Cu0030'}); otherwise, the first character of
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* the representation of the magnitude will not be the zero
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* character. The following ASCII characters are used as digits:
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*
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* <blockquote>
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* {@code 0123456789abcdefghijklmnopqrstuvwxyz}
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* </blockquote>
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*
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* These are {@code '\u005Cu0030'} through
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* {@code '\u005Cu0039'} and {@code '\u005Cu0061'} through
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* {@code '\u005Cu007a'}. If {@code radix} is
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* <var>N</var>, then the first <var>N</var> of these characters
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* are used as radix-<var>N</var> digits in the order shown. Thus,
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* the digits for hexadecimal (radix 16) are
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* {@code 0123456789abcdef}. If uppercase letters are
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* desired, the {@link java.lang.String#toUpperCase()} method may
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* be called on the result:
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*
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* <blockquote>
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* {@code Long.toString(n, 16).toUpperCase()}
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* </blockquote>
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*
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* @param i a {@code long} to be converted to a string.
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* @param radix the radix to use in the string representation.
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* @return a string representation of the argument in the specified radix.
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* @see java.lang.Character#MAX_RADIX
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* @see java.lang.Character#MIN_RADIX
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*/
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public static String toString(long i, int radix) {
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if (radix < Character.MIN_RADIX || radix > Character.MAX_RADIX)
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radix = 10;
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if (radix == 10)
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return toString(i);
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// BEGIN Android-changed: Use single-byte chars.
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/*
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if (COMPACT_STRINGS) {
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*/
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byte[] buf = new byte[65];
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int charPos = 64;
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boolean negative = (i < 0);
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if (!negative) {
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i = -i;
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}
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while (i <= -radix) {
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buf[charPos--] = (byte)Integer.digits[(int)(-(i % radix))];
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i = i / radix;
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}
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buf[charPos] = (byte)Integer.digits[(int)(-i)];
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if (negative) {
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buf[--charPos] = '-';
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}
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/*
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return StringLatin1.newString(buf, charPos, (65 - charPos));
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}
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return toStringUTF16(i, radix);
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*/
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return new String(buf, charPos, (65 - charPos));
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// END Android-changed: Use single-byte chars.
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}
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// BEGIN Android-removed: UTF16 version of toString(long i, int radix).
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/*
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private static String toStringUTF16(long i, int radix) {
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byte[] buf = new byte[65 * 2];
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int charPos = 64;
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boolean negative = (i < 0);
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if (!negative) {
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i = -i;
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}
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while (i <= -radix) {
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StringUTF16.putChar(buf, charPos--, Integer.digits[(int)(-(i % radix))]);
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i = i / radix;
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}
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StringUTF16.putChar(buf, charPos, Integer.digits[(int)(-i)]);
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if (negative) {
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StringUTF16.putChar(buf, --charPos, '-');
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}
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return StringUTF16.newString(buf, charPos, (65 - charPos));
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}
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*/
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// END Android-removed: UTF16 version of toString(long i, int radix).
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/**
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* Returns a string representation of the first argument as an
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* unsigned integer value in the radix specified by the second
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* argument.
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*
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* <p>If the radix is smaller than {@code Character.MIN_RADIX}
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* or larger than {@code Character.MAX_RADIX}, then the radix
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* {@code 10} is used instead.
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*
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* <p>Note that since the first argument is treated as an unsigned
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* value, no leading sign character is printed.
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*
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* <p>If the magnitude is zero, it is represented by a single zero
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* character {@code '0'} ({@code '\u005Cu0030'}); otherwise,
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* the first character of the representation of the magnitude will
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* not be the zero character.
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*
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* <p>The behavior of radixes and the characters used as digits
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* are the same as {@link #toString(long, int) toString}.
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*
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* @param i an integer to be converted to an unsigned string.
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* @param radix the radix to use in the string representation.
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* @return an unsigned string representation of the argument in the specified radix.
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* @see #toString(long, int)
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* @since 1.8
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*/
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public static String toUnsignedString(long i, int radix) {
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if (i >= 0)
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return toString(i, radix);
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else {
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return switch (radix) {
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case 2 -> toBinaryString(i);
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case 4 -> toUnsignedString0(i, 2);
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case 8 -> toOctalString(i);
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case 10 -> {
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/*
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* We can get the effect of an unsigned division by 10
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* on a long value by first shifting right, yielding a
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* positive value, and then dividing by 5. This
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* allows the last digit and preceding digits to be
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* isolated more quickly than by an initial conversion
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* to BigInteger.
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*/
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long quot = (i >>> 1) / 5;
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long rem = i - quot * 10;
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yield toString(quot) + rem;
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}
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case 16 -> toHexString(i);
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case 32 -> toUnsignedString0(i, 5);
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default -> toUnsignedBigInteger(i).toString(radix);
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};
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}
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}
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/**
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* Return a BigInteger equal to the unsigned value of the
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* argument.
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*/
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private static BigInteger toUnsignedBigInteger(long i) {
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if (i >= 0L)
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return BigInteger.valueOf(i);
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else {
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int upper = (int) (i >>> 32);
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int lower = (int) i;
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// return (upper << 32) + lower
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return (BigInteger.valueOf(Integer.toUnsignedLong(upper))).shiftLeft(32).
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add(BigInteger.valueOf(Integer.toUnsignedLong(lower)));
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}
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}
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// Android-removed: java.util.HexFormat references in javadoc as not present.
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/**
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* Returns a string representation of the {@code long}
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* argument as an unsigned integer in base 16.
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*
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* <p>The unsigned {@code long} value is the argument plus
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* 2<sup>64</sup> if the argument is negative; otherwise, it is
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* equal to the argument. This value is converted to a string of
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* ASCII digits in hexadecimal (base 16) with no extra
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* leading {@code 0}s.
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*
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* <p>The value of the argument can be recovered from the returned
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* string {@code s} by calling {@link
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* Long#parseUnsignedLong(String, int) Long.parseUnsignedLong(s,
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* 16)}.
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*
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* <p>If the unsigned magnitude is zero, it is represented by a
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* single zero character {@code '0'} ({@code '\u005Cu0030'});
|
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* otherwise, the first character of the representation of the
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* unsigned magnitude will not be the zero character. The
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* following characters are used as hexadecimal digits:
|
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*
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|
* <blockquote>
|
|
* {@code 0123456789abcdef}
|
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* </blockquote>
|
|
*
|
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* These are the characters {@code '\u005Cu0030'} through
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* {@code '\u005Cu0039'} and {@code '\u005Cu0061'} through
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* {@code '\u005Cu0066'}. If uppercase letters are desired,
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* the {@link java.lang.String#toUpperCase()} method may be called
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* on the result:
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*
|
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* <blockquote>
|
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* {@code Long.toHexString(n).toUpperCase()}
|
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* </blockquote>
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*
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* @param i a {@code long} to be converted to a string.
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* @return the string representation of the unsigned {@code long}
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* value represented by the argument in hexadecimal
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* (base 16).
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* @see #parseUnsignedLong(String, int)
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* @see #toUnsignedString(long, int)
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* @since 1.0.2
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*/
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public static String toHexString(long i) {
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return toUnsignedString0(i, 4);
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}
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/**
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* Returns a string representation of the {@code long}
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* argument as an unsigned integer in base 8.
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*
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* <p>The unsigned {@code long} value is the argument plus
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* 2<sup>64</sup> if the argument is negative; otherwise, it is
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* equal to the argument. This value is converted to a string of
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* ASCII digits in octal (base 8) with no extra leading
|
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* {@code 0}s.
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*
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* <p>The value of the argument can be recovered from the returned
|
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* string {@code s} by calling {@link
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* Long#parseUnsignedLong(String, int) Long.parseUnsignedLong(s,
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* 8)}.
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*
|
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* <p>If the unsigned magnitude is zero, it is represented by a
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* single zero character {@code '0'} ({@code '\u005Cu0030'});
|
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* otherwise, the first character of the representation of the
|
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* unsigned magnitude will not be the zero character. The
|
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* following characters are used as octal digits:
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*
|
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* <blockquote>
|
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* {@code 01234567}
|
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* </blockquote>
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*
|
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* These are the characters {@code '\u005Cu0030'} through
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* {@code '\u005Cu0037'}.
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*
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* @param i a {@code long} to be converted to a string.
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* @return the string representation of the unsigned {@code long}
|
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* value represented by the argument in octal (base 8).
|
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* @see #parseUnsignedLong(String, int)
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* @see #toUnsignedString(long, int)
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* @since 1.0.2
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*/
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public static String toOctalString(long i) {
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return toUnsignedString0(i, 3);
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}
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/**
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* Returns a string representation of the {@code long}
|
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* argument as an unsigned integer in base 2.
|
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*
|
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* <p>The unsigned {@code long} value is the argument plus
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* 2<sup>64</sup> if the argument is negative; otherwise, it is
|
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* equal to the argument. This value is converted to a string of
|
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* ASCII digits in binary (base 2) with no extra leading
|
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* {@code 0}s.
|
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*
|
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* <p>The value of the argument can be recovered from the returned
|
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* string {@code s} by calling {@link
|
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* Long#parseUnsignedLong(String, int) Long.parseUnsignedLong(s,
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* 2)}.
|
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*
|
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* <p>If the unsigned magnitude is zero, it is represented by a
|
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* single zero character {@code '0'} ({@code '\u005Cu0030'});
|
|
* otherwise, the first character of the representation of the
|
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* unsigned magnitude will not be the zero character. The
|
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* characters {@code '0'} ({@code '\u005Cu0030'}) and {@code
|
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* '1'} ({@code '\u005Cu0031'}) are used as binary digits.
|
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*
|
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* @param i a {@code long} to be converted to a string.
|
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* @return the string representation of the unsigned {@code long}
|
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* value represented by the argument in binary (base 2).
|
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* @see #parseUnsignedLong(String, int)
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* @see #toUnsignedString(long, int)
|
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* @since 1.0.2
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*/
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public static String toBinaryString(long i) {
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return toUnsignedString0(i, 1);
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}
|
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|
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/**
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* Format a long (treated as unsigned) into a String.
|
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* @param val the value to format
|
|
* @param shift the log2 of the base to format in (4 for hex, 3 for octal, 1 for binary)
|
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*/
|
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static String toUnsignedString0(long val, int shift) {
|
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// assert shift > 0 && shift <=5 : "Illegal shift value";
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int mag = Long.SIZE - Long.numberOfLeadingZeros(val);
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int chars = Math.max(((mag + (shift - 1)) / shift), 1);
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|
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// BEGIN Android-changed: Use single-byte chars.
|
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/*
|
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if (COMPACT_STRINGS) {
|
|
*/
|
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byte[] buf = new byte[chars];
|
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formatUnsignedLong0(val, shift, buf, 0, chars);
|
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/*
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return new String(buf, LATIN1);
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} else {
|
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byte[] buf = new byte[chars * 2];
|
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formatUnsignedLong0UTF16(val, shift, buf, 0, chars);
|
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return new String(buf, UTF16);
|
|
}
|
|
*/
|
|
return new String(buf);
|
|
// END Android-changed: Use single-byte chars.
|
|
}
|
|
|
|
/**
|
|
* Format a long (treated as unsigned) into a byte buffer (LATIN1 version). If
|
|
* {@code len} exceeds the formatted ASCII representation of {@code val},
|
|
* {@code buf} will be padded with leading zeroes.
|
|
*
|
|
* @param val the unsigned long to format
|
|
* @param shift the log2 of the base to format in (4 for hex, 3 for octal, 1 for binary)
|
|
* @param buf the byte buffer to write to
|
|
* @param offset the offset in the destination buffer to start at
|
|
* @param len the number of characters to write
|
|
*/
|
|
// Android-changed: dropped private modifier
|
|
static void formatUnsignedLong0(long val, int shift, byte[] buf, int offset, int len) {
|
|
int charPos = offset + len;
|
|
int radix = 1 << shift;
|
|
int mask = radix - 1;
|
|
do {
|
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buf[--charPos] = (byte)Integer.digits[((int) val) & mask];
|
|
val >>>= shift;
|
|
} while (charPos > offset);
|
|
}
|
|
|
|
// BEGIN Android-removed: UTF16 version of formatUnsignedLong0().
|
|
/*
|
|
/** byte[]/UTF16 version *
|
|
private static void formatUnsignedLong0UTF16(long val, int shift, byte[] buf, int offset, int len) {
|
|
int charPos = offset + len;
|
|
int radix = 1 << shift;
|
|
int mask = radix - 1;
|
|
do {
|
|
StringUTF16.putChar(buf, --charPos, Integer.digits[((int) val) & mask]);
|
|
val >>>= shift;
|
|
} while (charPos > offset);
|
|
}
|
|
*/
|
|
// END Android-removed: UTF16 version of formatUnsignedLong0().
|
|
|
|
/**
|
|
* Returns a {@code String} object representing the specified
|
|
* {@code long}. The argument is converted to signed decimal
|
|
* representation and returned as a string, exactly as if the
|
|
* argument and the radix 10 were given as arguments to the {@link
|
|
* #toString(long, int)} method.
|
|
*
|
|
* @param i a {@code long} to be converted.
|
|
* @return a string representation of the argument in base 10.
|
|
*/
|
|
public static String toString(long i) {
|
|
int size = stringSize(i);
|
|
// BEGIN Android-changed: Always use single-byte buffer.
|
|
/*
|
|
if (COMPACT_STRINGS) {
|
|
*/
|
|
byte[] buf = new byte[size];
|
|
getChars(i, size, buf);
|
|
/*
|
|
return new String(buf, LATIN1);
|
|
} else {
|
|
byte[] buf = new byte[size * 2];
|
|
StringUTF16.getChars(i, size, buf);
|
|
return new String(buf, UTF16);
|
|
}
|
|
*/
|
|
return new String(buf);
|
|
// END Android-changed: Always use single-byte buffer.
|
|
}
|
|
|
|
/**
|
|
* Returns a string representation of the argument as an unsigned
|
|
* decimal value.
|
|
*
|
|
* The argument is converted to unsigned decimal representation
|
|
* and returned as a string exactly as if the argument and radix
|
|
* 10 were given as arguments to the {@link #toUnsignedString(long,
|
|
* int)} method.
|
|
*
|
|
* @param i an integer to be converted to an unsigned string.
|
|
* @return an unsigned string representation of the argument.
|
|
* @see #toUnsignedString(long, int)
|
|
* @since 1.8
|
|
*/
|
|
public static String toUnsignedString(long i) {
|
|
return toUnsignedString(i, 10);
|
|
}
|
|
|
|
/**
|
|
* Places characters representing the long i into the
|
|
* character array buf. The characters are placed into
|
|
* the buffer backwards starting with the least significant
|
|
* digit at the specified index (exclusive), and working
|
|
* backwards from there.
|
|
*
|
|
* @implNote This method converts positive inputs into negative
|
|
* values, to cover the Long.MIN_VALUE case. Converting otherwise
|
|
* (negative to positive) will expose -Long.MIN_VALUE that overflows
|
|
* long.
|
|
*
|
|
* @param i value to convert
|
|
* @param index next index, after the least significant digit
|
|
* @param buf target buffer, Latin1-encoded
|
|
* @return index of the most significant digit or minus sign, if present
|
|
*/
|
|
static int getChars(long i, int index, byte[] buf) {
|
|
long q;
|
|
int r;
|
|
int charPos = index;
|
|
|
|
boolean negative = (i < 0);
|
|
if (!negative) {
|
|
i = -i;
|
|
}
|
|
|
|
// Get 2 digits/iteration using longs until quotient fits into an int
|
|
while (i <= Integer.MIN_VALUE) {
|
|
q = i / 100;
|
|
r = (int)((q * 100) - i);
|
|
i = q;
|
|
buf[--charPos] = Integer.DigitOnes[r];
|
|
buf[--charPos] = Integer.DigitTens[r];
|
|
}
|
|
|
|
// Get 2 digits/iteration using ints
|
|
int q2;
|
|
int i2 = (int)i;
|
|
while (i2 <= -100) {
|
|
q2 = i2 / 100;
|
|
r = (q2 * 100) - i2;
|
|
i2 = q2;
|
|
buf[--charPos] = Integer.DigitOnes[r];
|
|
buf[--charPos] = Integer.DigitTens[r];
|
|
}
|
|
|
|
// We know there are at most two digits left at this point.
|
|
q2 = i2 / 10;
|
|
r = (q2 * 10) - i2;
|
|
buf[--charPos] = (byte)('0' + r);
|
|
|
|
// Whatever left is the remaining digit.
|
|
if (q2 < 0) {
|
|
buf[--charPos] = (byte)('0' - q2);
|
|
}
|
|
|
|
if (negative) {
|
|
buf[--charPos] = (byte)'-';
|
|
}
|
|
return charPos;
|
|
}
|
|
|
|
// BEGIN Android-added: char version of getChars(long i, int index, byte[] buf).
|
|
// for java.lang.AbstractStringBuilder#append(int).
|
|
static int getChars(long i, int index, char[] buf) {
|
|
long q;
|
|
int r;
|
|
int charPos = index;
|
|
|
|
boolean negative = (i < 0);
|
|
if (!negative) {
|
|
i = -i;
|
|
}
|
|
|
|
// Get 2 digits/iteration using longs until quotient fits into an int
|
|
while (i <= Integer.MIN_VALUE) {
|
|
q = i / 100;
|
|
r = (int)((q * 100) - i);
|
|
i = q;
|
|
buf[--charPos] = (char)Integer.DigitOnes[r];
|
|
buf[--charPos] = (char)Integer.DigitTens[r];
|
|
}
|
|
|
|
// Get 2 digits/iteration using ints
|
|
int q2;
|
|
int i2 = (int)i;
|
|
while (i2 <= -100) {
|
|
q2 = i2 / 100;
|
|
r = (q2 * 100) - i2;
|
|
i2 = q2;
|
|
buf[--charPos] = (char)Integer.DigitOnes[r];
|
|
buf[--charPos] = (char)Integer.DigitTens[r];
|
|
}
|
|
|
|
// We know there are at most two digits left at this point.
|
|
q2 = i2 / 10;
|
|
r = (q2 * 10) - i2;
|
|
buf[--charPos] = (char)('0' + r);
|
|
|
|
// Whatever left is the remaining digit.
|
|
if (q2 < 0) {
|
|
buf[--charPos] = (char)('0' - q2);
|
|
}
|
|
|
|
if (negative) {
|
|
buf[--charPos] = (byte)'-';
|
|
}
|
|
return charPos;
|
|
}
|
|
// END Android-added: char version of getChars(long i, int index, byte[] buf).
|
|
|
|
/**
|
|
* Returns the string representation size for a given long value.
|
|
*
|
|
* @param x long value
|
|
* @return string size
|
|
*
|
|
* @implNote There are other ways to compute this: e.g. binary search,
|
|
* but values are biased heavily towards zero, and therefore linear search
|
|
* wins. The iteration results are also routinely inlined in the generated
|
|
* code after loop unrolling.
|
|
*/
|
|
static int stringSize(long x) {
|
|
int d = 1;
|
|
if (x >= 0) {
|
|
d = 0;
|
|
x = -x;
|
|
}
|
|
long p = -10;
|
|
for (int i = 1; i < 19; i++) {
|
|
if (x > p)
|
|
return i + d;
|
|
p = 10 * p;
|
|
}
|
|
return 19 + d;
|
|
}
|
|
|
|
/**
|
|
* Parses the string argument as a signed {@code long} in the
|
|
* radix specified by the second argument. The characters in the
|
|
* string must all be digits of the specified radix (as determined
|
|
* by whether {@link java.lang.Character#digit(char, int)} returns
|
|
* a nonnegative value), except that the first character may be an
|
|
* ASCII minus sign {@code '-'} ({@code '\u005Cu002D'}) to
|
|
* indicate a negative value or an ASCII plus sign {@code '+'}
|
|
* ({@code '\u005Cu002B'}) to indicate a positive value. The
|
|
* resulting {@code long} value is returned.
|
|
*
|
|
* <p>Note that neither the character {@code L}
|
|
* ({@code '\u005Cu004C'}) nor {@code l}
|
|
* ({@code '\u005Cu006C'}) is permitted to appear at the end
|
|
* of the string as a type indicator, as would be permitted in
|
|
* Java programming language source code - except that either
|
|
* {@code L} or {@code l} may appear as a digit for a
|
|
* radix greater than or equal to 22.
|
|
*
|
|
* <p>An exception of type {@code NumberFormatException} is
|
|
* thrown if any of the following situations occurs:
|
|
* <ul>
|
|
*
|
|
* <li>The first argument is {@code null} or is a string of
|
|
* length zero.
|
|
*
|
|
* <li>The {@code radix} is either smaller than {@link
|
|
* java.lang.Character#MIN_RADIX} or larger than {@link
|
|
* java.lang.Character#MAX_RADIX}.
|
|
*
|
|
* <li>Any character of the string is not a digit of the specified
|
|
* radix, except that the first character may be a minus sign
|
|
* {@code '-'} ({@code '\u005Cu002d'}) or plus sign {@code
|
|
* '+'} ({@code '\u005Cu002B'}) provided that the string is
|
|
* longer than length 1.
|
|
*
|
|
* <li>The value represented by the string is not a value of type
|
|
* {@code long}.
|
|
* </ul>
|
|
*
|
|
* <p>Examples:
|
|
* <blockquote><pre>
|
|
* parseLong("0", 10) returns 0L
|
|
* parseLong("473", 10) returns 473L
|
|
* parseLong("+42", 10) returns 42L
|
|
* parseLong("-0", 10) returns 0L
|
|
* parseLong("-FF", 16) returns -255L
|
|
* parseLong("1100110", 2) returns 102L
|
|
* parseLong("99", 8) throws a NumberFormatException
|
|
* parseLong("Hazelnut", 10) throws a NumberFormatException
|
|
* parseLong("Hazelnut", 36) returns 1356099454469L
|
|
* </pre></blockquote>
|
|
*
|
|
* @param s the {@code String} containing the
|
|
* {@code long} representation to be parsed.
|
|
* @param radix the radix to be used while parsing {@code s}.
|
|
* @return the {@code long} represented by the string argument in
|
|
* the specified radix.
|
|
* @throws NumberFormatException if the string does not contain a
|
|
* parsable {@code long}.
|
|
*/
|
|
public static long parseLong(String s, int radix)
|
|
throws NumberFormatException
|
|
{
|
|
if (s == null) {
|
|
throw new NumberFormatException("Cannot parse null string");
|
|
}
|
|
|
|
if (radix < Character.MIN_RADIX) {
|
|
throw new NumberFormatException("radix " + radix +
|
|
" less than Character.MIN_RADIX");
|
|
}
|
|
if (radix > Character.MAX_RADIX) {
|
|
throw new NumberFormatException("radix " + radix +
|
|
" greater than Character.MAX_RADIX");
|
|
}
|
|
|
|
boolean negative = false;
|
|
int i = 0, len = s.length();
|
|
long limit = -Long.MAX_VALUE;
|
|
|
|
if (len > 0) {
|
|
char firstChar = s.charAt(0);
|
|
if (firstChar < '0') { // Possible leading "+" or "-"
|
|
if (firstChar == '-') {
|
|
negative = true;
|
|
limit = Long.MIN_VALUE;
|
|
} else if (firstChar != '+') {
|
|
throw NumberFormatException.forInputString(s, radix);
|
|
}
|
|
|
|
if (len == 1) { // Cannot have lone "+" or "-"
|
|
throw NumberFormatException.forInputString(s, radix);
|
|
}
|
|
i++;
|
|
}
|
|
long multmin = limit / radix;
|
|
long result = 0;
|
|
while (i < len) {
|
|
// Accumulating negatively avoids surprises near MAX_VALUE
|
|
int digit = Character.digit(s.charAt(i++),radix);
|
|
if (digit < 0 || result < multmin) {
|
|
throw NumberFormatException.forInputString(s, radix);
|
|
}
|
|
result *= radix;
|
|
if (result < limit + digit) {
|
|
throw NumberFormatException.forInputString(s, radix);
|
|
}
|
|
result -= digit;
|
|
}
|
|
return negative ? result : -result;
|
|
} else {
|
|
throw NumberFormatException.forInputString(s, radix);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Parses the {@link CharSequence} argument as a signed {@code long} in
|
|
* the specified {@code radix}, beginning at the specified
|
|
* {@code beginIndex} and extending to {@code endIndex - 1}.
|
|
*
|
|
* <p>The method does not take steps to guard against the
|
|
* {@code CharSequence} being mutated while parsing.
|
|
*
|
|
* @param s the {@code CharSequence} containing the {@code long}
|
|
* representation to be parsed
|
|
* @param beginIndex the beginning index, inclusive.
|
|
* @param endIndex the ending index, exclusive.
|
|
* @param radix the radix to be used while parsing {@code s}.
|
|
* @return the signed {@code long} represented by the subsequence in
|
|
* the specified radix.
|
|
* @throws NullPointerException if {@code s} is null.
|
|
* @throws IndexOutOfBoundsException if {@code beginIndex} is
|
|
* negative, or if {@code beginIndex} is greater than
|
|
* {@code endIndex} or if {@code endIndex} is greater than
|
|
* {@code s.length()}.
|
|
* @throws NumberFormatException if the {@code CharSequence} does not
|
|
* contain a parsable {@code long} in the specified
|
|
* {@code radix}, or if {@code radix} is either smaller than
|
|
* {@link java.lang.Character#MIN_RADIX} or larger than
|
|
* {@link java.lang.Character#MAX_RADIX}.
|
|
* @since 9
|
|
*/
|
|
public static long parseLong(CharSequence s, int beginIndex, int endIndex, int radix)
|
|
throws NumberFormatException {
|
|
Objects.requireNonNull(s);
|
|
|
|
if (beginIndex < 0 || beginIndex > endIndex || endIndex > s.length()) {
|
|
throw new IndexOutOfBoundsException();
|
|
}
|
|
if (radix < Character.MIN_RADIX) {
|
|
throw new NumberFormatException("radix " + radix +
|
|
" less than Character.MIN_RADIX");
|
|
}
|
|
if (radix > Character.MAX_RADIX) {
|
|
throw new NumberFormatException("radix " + radix +
|
|
" greater than Character.MAX_RADIX");
|
|
}
|
|
|
|
boolean negative = false;
|
|
int i = beginIndex;
|
|
long limit = -Long.MAX_VALUE;
|
|
|
|
if (i < endIndex) {
|
|
char firstChar = s.charAt(i);
|
|
if (firstChar < '0') { // Possible leading "+" or "-"
|
|
if (firstChar == '-') {
|
|
negative = true;
|
|
limit = Long.MIN_VALUE;
|
|
} else if (firstChar != '+') {
|
|
throw NumberFormatException.forCharSequence(s, beginIndex,
|
|
endIndex, i);
|
|
}
|
|
i++;
|
|
}
|
|
if (i >= endIndex) { // Cannot have lone "+", "-" or ""
|
|
throw NumberFormatException.forCharSequence(s, beginIndex,
|
|
endIndex, i);
|
|
}
|
|
long multmin = limit / radix;
|
|
long result = 0;
|
|
while (i < endIndex) {
|
|
// Accumulating negatively avoids surprises near MAX_VALUE
|
|
int digit = Character.digit(s.charAt(i), radix);
|
|
if (digit < 0 || result < multmin) {
|
|
throw NumberFormatException.forCharSequence(s, beginIndex,
|
|
endIndex, i);
|
|
}
|
|
result *= radix;
|
|
if (result < limit + digit) {
|
|
throw NumberFormatException.forCharSequence(s, beginIndex,
|
|
endIndex, i);
|
|
}
|
|
i++;
|
|
result -= digit;
|
|
}
|
|
return negative ? result : -result;
|
|
} else {
|
|
throw new NumberFormatException("");
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Parses the string argument as a signed decimal {@code long}.
|
|
* The characters in the string must all be decimal digits, except
|
|
* that the first character may be an ASCII minus sign {@code '-'}
|
|
* ({@code \u005Cu002D'}) to indicate a negative value or an
|
|
* ASCII plus sign {@code '+'} ({@code '\u005Cu002B'}) to
|
|
* indicate a positive value. The resulting {@code long} value is
|
|
* returned, exactly as if the argument and the radix {@code 10}
|
|
* were given as arguments to the {@link
|
|
* #parseLong(java.lang.String, int)} method.
|
|
*
|
|
* <p>Note that neither the character {@code L}
|
|
* ({@code '\u005Cu004C'}) nor {@code l}
|
|
* ({@code '\u005Cu006C'}) is permitted to appear at the end
|
|
* of the string as a type indicator, as would be permitted in
|
|
* Java programming language source code.
|
|
*
|
|
* @param s a {@code String} containing the {@code long}
|
|
* representation to be parsed
|
|
* @return the {@code long} represented by the argument in
|
|
* decimal.
|
|
* @throws NumberFormatException if the string does not contain a
|
|
* parsable {@code long}.
|
|
*/
|
|
public static long parseLong(String s) throws NumberFormatException {
|
|
return parseLong(s, 10);
|
|
}
|
|
|
|
/**
|
|
* Parses the string argument as an unsigned {@code long} in the
|
|
* radix specified by the second argument. An unsigned integer
|
|
* maps the values usually associated with negative numbers to
|
|
* positive numbers larger than {@code MAX_VALUE}.
|
|
*
|
|
* The characters in the string must all be digits of the
|
|
* specified radix (as determined by whether {@link
|
|
* java.lang.Character#digit(char, int)} returns a nonnegative
|
|
* value), except that the first character may be an ASCII plus
|
|
* sign {@code '+'} ({@code '\u005Cu002B'}). The resulting
|
|
* integer value is returned.
|
|
*
|
|
* <p>An exception of type {@code NumberFormatException} is
|
|
* thrown if any of the following situations occurs:
|
|
* <ul>
|
|
* <li>The first argument is {@code null} or is a string of
|
|
* length zero.
|
|
*
|
|
* <li>The radix is either smaller than
|
|
* {@link java.lang.Character#MIN_RADIX} or
|
|
* larger than {@link java.lang.Character#MAX_RADIX}.
|
|
*
|
|
* <li>Any character of the string is not a digit of the specified
|
|
* radix, except that the first character may be a plus sign
|
|
* {@code '+'} ({@code '\u005Cu002B'}) provided that the
|
|
* string is longer than length 1.
|
|
*
|
|
* <li>The value represented by the string is larger than the
|
|
* largest unsigned {@code long}, 2<sup>64</sup>-1.
|
|
*
|
|
* </ul>
|
|
*
|
|
*
|
|
* @param s the {@code String} containing the unsigned integer
|
|
* representation to be parsed
|
|
* @param radix the radix to be used while parsing {@code s}.
|
|
* @return the unsigned {@code long} represented by the string
|
|
* argument in the specified radix.
|
|
* @throws NumberFormatException if the {@code String}
|
|
* does not contain a parsable {@code long}.
|
|
* @since 1.8
|
|
*/
|
|
public static long parseUnsignedLong(String s, int radix)
|
|
throws NumberFormatException {
|
|
if (s == null) {
|
|
throw new NumberFormatException("Cannot parse null string");
|
|
}
|
|
|
|
int len = s.length();
|
|
if (len > 0) {
|
|
char firstChar = s.charAt(0);
|
|
if (firstChar == '-') {
|
|
throw new
|
|
NumberFormatException(String.format("Illegal leading minus sign " +
|
|
"on unsigned string %s.", s));
|
|
} else {
|
|
if (len <= 12 || // Long.MAX_VALUE in Character.MAX_RADIX is 13 digits
|
|
(radix == 10 && len <= 18) ) { // Long.MAX_VALUE in base 10 is 19 digits
|
|
return parseLong(s, radix);
|
|
}
|
|
|
|
// No need for range checks on len due to testing above.
|
|
long first = parseLong(s, 0, len - 1, radix);
|
|
int second = Character.digit(s.charAt(len - 1), radix);
|
|
if (second < 0) {
|
|
throw new NumberFormatException("Bad digit at end of " + s);
|
|
}
|
|
long result = first * radix + second;
|
|
|
|
/*
|
|
* Test leftmost bits of multiprecision extension of first*radix
|
|
* for overflow. The number of bits needed is defined by
|
|
* GUARD_BIT = ceil(log2(Character.MAX_RADIX)) + 1 = 7. Then
|
|
* int guard = radix*(int)(first >>> (64 - GUARD_BIT)) and
|
|
* overflow is tested by splitting guard in the ranges
|
|
* guard < 92, 92 <= guard < 128, and 128 <= guard, where
|
|
* 92 = 128 - Character.MAX_RADIX. Note that guard cannot take
|
|
* on a value which does not include a prime factor in the legal
|
|
* radix range.
|
|
*/
|
|
int guard = radix * (int) (first >>> 57);
|
|
if (guard >= 128 ||
|
|
(result >= 0 && guard >= 128 - Character.MAX_RADIX)) {
|
|
/*
|
|
* For purposes of exposition, the programmatic statements
|
|
* below should be taken to be multi-precision, i.e., not
|
|
* subject to overflow.
|
|
*
|
|
* A) Condition guard >= 128:
|
|
* If guard >= 128 then first*radix >= 2^7 * 2^57 = 2^64
|
|
* hence always overflow.
|
|
*
|
|
* B) Condition guard < 92:
|
|
* Define left7 = first >>> 57.
|
|
* Given first = (left7 * 2^57) + (first & (2^57 - 1)) then
|
|
* result <= (radix*left7)*2^57 + radix*(2^57 - 1) + second.
|
|
* Thus if radix*left7 < 92, radix <= 36, and second < 36,
|
|
* then result < 92*2^57 + 36*(2^57 - 1) + 36 = 2^64 hence
|
|
* never overflow.
|
|
*
|
|
* C) Condition 92 <= guard < 128:
|
|
* first*radix + second >= radix*left7*2^57 + second
|
|
* so that first*radix + second >= 92*2^57 + 0 > 2^63
|
|
*
|
|
* D) Condition guard < 128:
|
|
* radix*first <= (radix*left7) * 2^57 + radix*(2^57 - 1)
|
|
* so
|
|
* radix*first + second <= (radix*left7) * 2^57 + radix*(2^57 - 1) + 36
|
|
* thus
|
|
* radix*first + second < 128 * 2^57 + 36*2^57 - radix + 36
|
|
* whence
|
|
* radix*first + second < 2^64 + 2^6*2^57 = 2^64 + 2^63
|
|
*
|
|
* E) Conditions C, D, and result >= 0:
|
|
* C and D combined imply the mathematical result
|
|
* 2^63 < first*radix + second < 2^64 + 2^63. The lower
|
|
* bound is therefore negative as a signed long, but the
|
|
* upper bound is too small to overflow again after the
|
|
* signed long overflows to positive above 2^64 - 1. Hence
|
|
* result >= 0 implies overflow given C and D.
|
|
*/
|
|
throw new NumberFormatException(String.format("String value %s exceeds " +
|
|
"range of unsigned long.", s));
|
|
}
|
|
return result;
|
|
}
|
|
} else {
|
|
throw NumberFormatException.forInputString(s, radix);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Parses the {@link CharSequence} argument as an unsigned {@code long} in
|
|
* the specified {@code radix}, beginning at the specified
|
|
* {@code beginIndex} and extending to {@code endIndex - 1}.
|
|
*
|
|
* <p>The method does not take steps to guard against the
|
|
* {@code CharSequence} being mutated while parsing.
|
|
*
|
|
* @param s the {@code CharSequence} containing the unsigned
|
|
* {@code long} representation to be parsed
|
|
* @param beginIndex the beginning index, inclusive.
|
|
* @param endIndex the ending index, exclusive.
|
|
* @param radix the radix to be used while parsing {@code s}.
|
|
* @return the unsigned {@code long} represented by the subsequence in
|
|
* the specified radix.
|
|
* @throws NullPointerException if {@code s} is null.
|
|
* @throws IndexOutOfBoundsException if {@code beginIndex} is
|
|
* negative, or if {@code beginIndex} is greater than
|
|
* {@code endIndex} or if {@code endIndex} is greater than
|
|
* {@code s.length()}.
|
|
* @throws NumberFormatException if the {@code CharSequence} does not
|
|
* contain a parsable unsigned {@code long} in the specified
|
|
* {@code radix}, or if {@code radix} is either smaller than
|
|
* {@link java.lang.Character#MIN_RADIX} or larger than
|
|
* {@link java.lang.Character#MAX_RADIX}.
|
|
* @since 9
|
|
*/
|
|
public static long parseUnsignedLong(CharSequence s, int beginIndex, int endIndex, int radix)
|
|
throws NumberFormatException {
|
|
Objects.requireNonNull(s);
|
|
|
|
if (beginIndex < 0 || beginIndex > endIndex || endIndex > s.length()) {
|
|
throw new IndexOutOfBoundsException();
|
|
}
|
|
int start = beginIndex, len = endIndex - beginIndex;
|
|
|
|
if (len > 0) {
|
|
char firstChar = s.charAt(start);
|
|
if (firstChar == '-') {
|
|
throw new NumberFormatException(String.format("Illegal leading minus sign " +
|
|
"on unsigned string %s.", s.subSequence(start, start + len)));
|
|
} else {
|
|
if (len <= 12 || // Long.MAX_VALUE in Character.MAX_RADIX is 13 digits
|
|
(radix == 10 && len <= 18) ) { // Long.MAX_VALUE in base 10 is 19 digits
|
|
return parseLong(s, start, start + len, radix);
|
|
}
|
|
|
|
// No need for range checks on end due to testing above.
|
|
long first = parseLong(s, start, start + len - 1, radix);
|
|
int second = Character.digit(s.charAt(start + len - 1), radix);
|
|
if (second < 0) {
|
|
throw new NumberFormatException("Bad digit at end of " +
|
|
s.subSequence(start, start + len));
|
|
}
|
|
long result = first * radix + second;
|
|
|
|
/*
|
|
* Test leftmost bits of multiprecision extension of first*radix
|
|
* for overflow. The number of bits needed is defined by
|
|
* GUARD_BIT = ceil(log2(Character.MAX_RADIX)) + 1 = 7. Then
|
|
* int guard = radix*(int)(first >>> (64 - GUARD_BIT)) and
|
|
* overflow is tested by splitting guard in the ranges
|
|
* guard < 92, 92 <= guard < 128, and 128 <= guard, where
|
|
* 92 = 128 - Character.MAX_RADIX. Note that guard cannot take
|
|
* on a value which does not include a prime factor in the legal
|
|
* radix range.
|
|
*/
|
|
int guard = radix * (int) (first >>> 57);
|
|
if (guard >= 128 ||
|
|
(result >= 0 && guard >= 128 - Character.MAX_RADIX)) {
|
|
/*
|
|
* For purposes of exposition, the programmatic statements
|
|
* below should be taken to be multi-precision, i.e., not
|
|
* subject to overflow.
|
|
*
|
|
* A) Condition guard >= 128:
|
|
* If guard >= 128 then first*radix >= 2^7 * 2^57 = 2^64
|
|
* hence always overflow.
|
|
*
|
|
* B) Condition guard < 92:
|
|
* Define left7 = first >>> 57.
|
|
* Given first = (left7 * 2^57) + (first & (2^57 - 1)) then
|
|
* result <= (radix*left7)*2^57 + radix*(2^57 - 1) + second.
|
|
* Thus if radix*left7 < 92, radix <= 36, and second < 36,
|
|
* then result < 92*2^57 + 36*(2^57 - 1) + 36 = 2^64 hence
|
|
* never overflow.
|
|
*
|
|
* C) Condition 92 <= guard < 128:
|
|
* first*radix + second >= radix*left7*2^57 + second
|
|
* so that first*radix + second >= 92*2^57 + 0 > 2^63
|
|
*
|
|
* D) Condition guard < 128:
|
|
* radix*first <= (radix*left7) * 2^57 + radix*(2^57 - 1)
|
|
* so
|
|
* radix*first + second <= (radix*left7) * 2^57 + radix*(2^57 - 1) + 36
|
|
* thus
|
|
* radix*first + second < 128 * 2^57 + 36*2^57 - radix + 36
|
|
* whence
|
|
* radix*first + second < 2^64 + 2^6*2^57 = 2^64 + 2^63
|
|
*
|
|
* E) Conditions C, D, and result >= 0:
|
|
* C and D combined imply the mathematical result
|
|
* 2^63 < first*radix + second < 2^64 + 2^63. The lower
|
|
* bound is therefore negative as a signed long, but the
|
|
* upper bound is too small to overflow again after the
|
|
* signed long overflows to positive above 2^64 - 1. Hence
|
|
* result >= 0 implies overflow given C and D.
|
|
*/
|
|
throw new NumberFormatException(String.format("String value %s exceeds " +
|
|
"range of unsigned long.", s.subSequence(start, start + len)));
|
|
}
|
|
return result;
|
|
}
|
|
} else {
|
|
throw NumberFormatException.forInputString("", radix);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Parses the string argument as an unsigned decimal {@code long}. The
|
|
* characters in the string must all be decimal digits, except
|
|
* that the first character may be an ASCII plus sign {@code
|
|
* '+'} ({@code '\u005Cu002B'}). The resulting integer value
|
|
* is returned, exactly as if the argument and the radix 10 were
|
|
* given as arguments to the {@link
|
|
* #parseUnsignedLong(java.lang.String, int)} method.
|
|
*
|
|
* @param s a {@code String} containing the unsigned {@code long}
|
|
* representation to be parsed
|
|
* @return the unsigned {@code long} value represented by the decimal string argument
|
|
* @throws NumberFormatException if the string does not contain a
|
|
* parsable unsigned integer.
|
|
* @since 1.8
|
|
*/
|
|
public static long parseUnsignedLong(String s) throws NumberFormatException {
|
|
return parseUnsignedLong(s, 10);
|
|
}
|
|
|
|
/**
|
|
* Returns a {@code Long} object holding the value
|
|
* extracted from the specified {@code String} when parsed
|
|
* with the radix given by the second argument. The first
|
|
* argument is interpreted as representing a signed
|
|
* {@code long} in the radix specified by the second
|
|
* argument, exactly as if the arguments were given to the {@link
|
|
* #parseLong(java.lang.String, int)} method. The result is a
|
|
* {@code Long} object that represents the {@code long}
|
|
* value specified by the string.
|
|
*
|
|
* <p>In other words, this method returns a {@code Long} object equal
|
|
* to the value of:
|
|
*
|
|
* <blockquote>
|
|
* {@code new Long(Long.parseLong(s, radix))}
|
|
* </blockquote>
|
|
*
|
|
* @param s the string to be parsed
|
|
* @param radix the radix to be used in interpreting {@code s}
|
|
* @return a {@code Long} object holding the value
|
|
* represented by the string argument in the specified
|
|
* radix.
|
|
* @throws NumberFormatException If the {@code String} does not
|
|
* contain a parsable {@code long}.
|
|
*/
|
|
public static Long valueOf(String s, int radix) throws NumberFormatException {
|
|
return Long.valueOf(parseLong(s, radix));
|
|
}
|
|
|
|
/**
|
|
* Returns a {@code Long} object holding the value
|
|
* of the specified {@code String}. The argument is
|
|
* interpreted as representing a signed decimal {@code long},
|
|
* exactly as if the argument were given to the {@link
|
|
* #parseLong(java.lang.String)} method. The result is a
|
|
* {@code Long} object that represents the integer value
|
|
* specified by the string.
|
|
*
|
|
* <p>In other words, this method returns a {@code Long} object
|
|
* equal to the value of:
|
|
*
|
|
* <blockquote>
|
|
* {@code new Long(Long.parseLong(s))}
|
|
* </blockquote>
|
|
*
|
|
* @param s the string to be parsed.
|
|
* @return a {@code Long} object holding the value
|
|
* represented by the string argument.
|
|
* @throws NumberFormatException If the string cannot be parsed
|
|
* as a {@code long}.
|
|
*/
|
|
public static Long valueOf(String s) throws NumberFormatException
|
|
{
|
|
return Long.valueOf(parseLong(s, 10));
|
|
}
|
|
|
|
private static class LongCache {
|
|
private LongCache() {}
|
|
|
|
static final Long[] cache;
|
|
static Long[] archivedCache;
|
|
|
|
static {
|
|
int size = -(-128) + 127 + 1;
|
|
|
|
// Load and use the archived cache if it exists
|
|
// Android-removed: CDS is not used on Android.
|
|
// CDS.initializeFromArchive(LongCache.class);
|
|
if (archivedCache == null || archivedCache.length != size) {
|
|
Long[] c = new Long[size];
|
|
long value = -128;
|
|
for(int i = 0; i < size; i++) {
|
|
c[i] = new Long(value++);
|
|
}
|
|
archivedCache = c;
|
|
}
|
|
cache = archivedCache;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Returns a {@code Long} instance representing the specified
|
|
* {@code long} value.
|
|
* If a new {@code Long} instance is not required, this method
|
|
* should generally be used in preference to the constructor
|
|
* {@link #Long(long)}, as this method is likely to yield
|
|
* significantly better space and time performance by caching
|
|
* frequently requested values.
|
|
*
|
|
* This method will always cache values in the range -128 to 127,
|
|
* inclusive, and may cache other values outside of this range.
|
|
*
|
|
* @param l a long value.
|
|
* @return a {@code Long} instance representing {@code l}.
|
|
* @since 1.5
|
|
*/
|
|
@IntrinsicCandidate
|
|
public static Long valueOf(long l) {
|
|
final int offset = 128;
|
|
if (l >= -128 && l <= 127) { // will cache
|
|
return LongCache.cache[(int)l + offset];
|
|
}
|
|
return new Long(l);
|
|
}
|
|
|
|
/**
|
|
* Decodes a {@code String} into a {@code Long}.
|
|
* Accepts decimal, hexadecimal, and octal numbers given by the
|
|
* following grammar:
|
|
*
|
|
* <blockquote>
|
|
* <dl>
|
|
* <dt><i>DecodableString:</i>
|
|
* <dd><i>Sign<sub>opt</sub> DecimalNumeral</i>
|
|
* <dd><i>Sign<sub>opt</sub></i> {@code 0x} <i>HexDigits</i>
|
|
* <dd><i>Sign<sub>opt</sub></i> {@code 0X} <i>HexDigits</i>
|
|
* <dd><i>Sign<sub>opt</sub></i> {@code #} <i>HexDigits</i>
|
|
* <dd><i>Sign<sub>opt</sub></i> {@code 0} <i>OctalDigits</i>
|
|
*
|
|
* <dt><i>Sign:</i>
|
|
* <dd>{@code -}
|
|
* <dd>{@code +}
|
|
* </dl>
|
|
* </blockquote>
|
|
*
|
|
* <i>DecimalNumeral</i>, <i>HexDigits</i>, and <i>OctalDigits</i>
|
|
* are as defined in section {@jls 3.10.1} of
|
|
* <cite>The Java Language Specification</cite>,
|
|
* except that underscores are not accepted between digits.
|
|
*
|
|
* <p>The sequence of characters following an optional
|
|
* sign and/or radix specifier ("{@code 0x}", "{@code 0X}",
|
|
* "{@code #}", or leading zero) is parsed as by the {@code
|
|
* Long.parseLong} method with the indicated radix (10, 16, or 8).
|
|
* This sequence of characters must represent a positive value or
|
|
* a {@link NumberFormatException} will be thrown. The result is
|
|
* negated if first character of the specified {@code String} is
|
|
* the minus sign. No whitespace characters are permitted in the
|
|
* {@code String}.
|
|
*
|
|
* @param nm the {@code String} to decode.
|
|
* @return a {@code Long} object holding the {@code long}
|
|
* value represented by {@code nm}
|
|
* @throws NumberFormatException if the {@code String} does not
|
|
* contain a parsable {@code long}.
|
|
* @see java.lang.Long#parseLong(String, int)
|
|
* @since 1.2
|
|
*/
|
|
public static Long decode(String nm) throws NumberFormatException {
|
|
int radix = 10;
|
|
int index = 0;
|
|
boolean negative = false;
|
|
Long result;
|
|
|
|
if (nm.isEmpty())
|
|
throw new NumberFormatException("Zero length string");
|
|
char firstChar = nm.charAt(0);
|
|
// Handle sign, if present
|
|
if (firstChar == '-') {
|
|
negative = true;
|
|
index++;
|
|
} else if (firstChar == '+')
|
|
index++;
|
|
|
|
// Handle radix specifier, if present
|
|
if (nm.startsWith("0x", index) || nm.startsWith("0X", index)) {
|
|
index += 2;
|
|
radix = 16;
|
|
}
|
|
else if (nm.startsWith("#", index)) {
|
|
index ++;
|
|
radix = 16;
|
|
}
|
|
else if (nm.startsWith("0", index) && nm.length() > 1 + index) {
|
|
index ++;
|
|
radix = 8;
|
|
}
|
|
|
|
if (nm.startsWith("-", index) || nm.startsWith("+", index))
|
|
throw new NumberFormatException("Sign character in wrong position");
|
|
|
|
try {
|
|
result = Long.valueOf(nm.substring(index), radix);
|
|
result = negative ? Long.valueOf(-result.longValue()) : result;
|
|
} catch (NumberFormatException e) {
|
|
// If number is Long.MIN_VALUE, we'll end up here. The next line
|
|
// handles this case, and causes any genuine format error to be
|
|
// rethrown.
|
|
String constant = negative ? ("-" + nm.substring(index))
|
|
: nm.substring(index);
|
|
result = Long.valueOf(constant, radix);
|
|
}
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* The value of the {@code Long}.
|
|
*
|
|
* @serial
|
|
*/
|
|
private final long value;
|
|
|
|
/**
|
|
* Constructs a newly allocated {@code Long} object that
|
|
* represents the specified {@code long} argument.
|
|
*
|
|
* @param value the value to be represented by the
|
|
* {@code Long} object.
|
|
*
|
|
* @deprecated
|
|
* It is rarely appropriate to use this constructor. The static factory
|
|
* {@link #valueOf(long)} is generally a better choice, as it is
|
|
* likely to yield significantly better space and time performance.
|
|
*/
|
|
// Android-changed: not yet forRemoval on Android.
|
|
@Deprecated(since="9"/*, forRemoval = true*/)
|
|
public Long(long value) {
|
|
this.value = value;
|
|
}
|
|
|
|
/**
|
|
* Constructs a newly allocated {@code Long} object that
|
|
* represents the {@code long} value indicated by the
|
|
* {@code String} parameter. The string is converted to a
|
|
* {@code long} value in exactly the manner used by the
|
|
* {@code parseLong} method for radix 10.
|
|
*
|
|
* @param s the {@code String} to be converted to a
|
|
* {@code Long}.
|
|
* @throws NumberFormatException if the {@code String} does not
|
|
* contain a parsable {@code long}.
|
|
*
|
|
* @deprecated
|
|
* It is rarely appropriate to use this constructor.
|
|
* Use {@link #parseLong(String)} to convert a string to a
|
|
* {@code long} primitive, or use {@link #valueOf(String)}
|
|
* to convert a string to a {@code Long} object.
|
|
*/
|
|
@Deprecated(since="9"/*, forRemoval = true*/)
|
|
public Long(String s) throws NumberFormatException {
|
|
this.value = parseLong(s, 10);
|
|
}
|
|
|
|
/**
|
|
* Returns the value of this {@code Long} as a {@code byte} after
|
|
* a narrowing primitive conversion.
|
|
* @jls 5.1.3 Narrowing Primitive Conversion
|
|
*/
|
|
public byte byteValue() {
|
|
return (byte)value;
|
|
}
|
|
|
|
/**
|
|
* Returns the value of this {@code Long} as a {@code short} after
|
|
* a narrowing primitive conversion.
|
|
* @jls 5.1.3 Narrowing Primitive Conversion
|
|
*/
|
|
public short shortValue() {
|
|
return (short)value;
|
|
}
|
|
|
|
/**
|
|
* Returns the value of this {@code Long} as an {@code int} after
|
|
* a narrowing primitive conversion.
|
|
* @jls 5.1.3 Narrowing Primitive Conversion
|
|
*/
|
|
public int intValue() {
|
|
return (int)value;
|
|
}
|
|
|
|
/**
|
|
* Returns the value of this {@code Long} as a
|
|
* {@code long} value.
|
|
*/
|
|
@IntrinsicCandidate
|
|
public long longValue() {
|
|
return value;
|
|
}
|
|
|
|
/**
|
|
* Returns the value of this {@code Long} as a {@code float} after
|
|
* a widening primitive conversion.
|
|
* @jls 5.1.2 Widening Primitive Conversion
|
|
*/
|
|
public float floatValue() {
|
|
return (float)value;
|
|
}
|
|
|
|
/**
|
|
* Returns the value of this {@code Long} as a {@code double}
|
|
* after a widening primitive conversion.
|
|
* @jls 5.1.2 Widening Primitive Conversion
|
|
*/
|
|
public double doubleValue() {
|
|
return (double)value;
|
|
}
|
|
|
|
/**
|
|
* Returns a {@code String} object representing this
|
|
* {@code Long}'s value. The value is converted to signed
|
|
* decimal representation and returned as a string, exactly as if
|
|
* the {@code long} value were given as an argument to the
|
|
* {@link java.lang.Long#toString(long)} method.
|
|
*
|
|
* @return a string representation of the value of this object in
|
|
* base 10.
|
|
*/
|
|
public String toString() {
|
|
return toString(value);
|
|
}
|
|
|
|
/**
|
|
* Returns a hash code for this {@code Long}. The result is
|
|
* the exclusive OR of the two halves of the primitive
|
|
* {@code long} value held by this {@code Long}
|
|
* object. That is, the hashcode is the value of the expression:
|
|
*
|
|
* <blockquote>
|
|
* {@code (int)(this.longValue()^(this.longValue()>>>32))}
|
|
* </blockquote>
|
|
*
|
|
* @return a hash code value for this object.
|
|
*/
|
|
@Override
|
|
public int hashCode() {
|
|
return Long.hashCode(value);
|
|
}
|
|
|
|
/**
|
|
* Returns a hash code for a {@code long} value; compatible with
|
|
* {@code Long.hashCode()}.
|
|
*
|
|
* @param value the value to hash
|
|
* @return a hash code value for a {@code long} value.
|
|
* @since 1.8
|
|
*/
|
|
public static int hashCode(long value) {
|
|
return (int)(value ^ (value >>> 32));
|
|
}
|
|
|
|
/**
|
|
* Compares this object to the specified object. The result is
|
|
* {@code true} if and only if the argument is not
|
|
* {@code null} and is a {@code Long} object that
|
|
* contains the same {@code long} value as this object.
|
|
*
|
|
* @param obj the object to compare with.
|
|
* @return {@code true} if the objects are the same;
|
|
* {@code false} otherwise.
|
|
*/
|
|
public boolean equals(Object obj) {
|
|
if (obj instanceof Long) {
|
|
return value == ((Long)obj).longValue();
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Determines the {@code long} value of the system property
|
|
* with the specified name.
|
|
*
|
|
* <p>The first argument is treated as the name of a system
|
|
* property. System properties are accessible through the {@link
|
|
* java.lang.System#getProperty(java.lang.String)} method. The
|
|
* string value of this property is then interpreted as a {@code
|
|
* long} value using the grammar supported by {@link Long#decode decode}
|
|
* and a {@code Long} object representing this value is returned.
|
|
*
|
|
* <p>If there is no property with the specified name, if the
|
|
* specified name is empty or {@code null}, or if the property
|
|
* does not have the correct numeric format, then {@code null} is
|
|
* returned.
|
|
*
|
|
* <p>In other words, this method returns a {@code Long} object
|
|
* equal to the value of:
|
|
*
|
|
* <blockquote>
|
|
* {@code getLong(nm, null)}
|
|
* </blockquote>
|
|
*
|
|
* @param nm property name.
|
|
* @return the {@code Long} value of the property.
|
|
* @throws SecurityException for the same reasons as
|
|
* {@link System#getProperty(String) System.getProperty}
|
|
* @see java.lang.System#getProperty(java.lang.String)
|
|
* @see java.lang.System#getProperty(java.lang.String, java.lang.String)
|
|
*/
|
|
public static Long getLong(String nm) {
|
|
return getLong(nm, null);
|
|
}
|
|
|
|
/**
|
|
* Determines the {@code long} value of the system property
|
|
* with the specified name.
|
|
*
|
|
* <p>The first argument is treated as the name of a system
|
|
* property. System properties are accessible through the {@link
|
|
* java.lang.System#getProperty(java.lang.String)} method. The
|
|
* string value of this property is then interpreted as a {@code
|
|
* long} value using the grammar supported by {@link Long#decode decode}
|
|
* and a {@code Long} object representing this value is returned.
|
|
*
|
|
* <p>The second argument is the default value. A {@code Long} object
|
|
* that represents the value of the second argument is returned if there
|
|
* is no property of the specified name, if the property does not have
|
|
* the correct numeric format, or if the specified name is empty or null.
|
|
*
|
|
* <p>In other words, this method returns a {@code Long} object equal
|
|
* to the value of:
|
|
*
|
|
* <blockquote>
|
|
* {@code getLong(nm, new Long(val))}
|
|
* </blockquote>
|
|
*
|
|
* but in practice it may be implemented in a manner such as:
|
|
*
|
|
* <blockquote><pre>
|
|
* Long result = getLong(nm, null);
|
|
* return (result == null) ? new Long(val) : result;
|
|
* </pre></blockquote>
|
|
*
|
|
* to avoid the unnecessary allocation of a {@code Long} object when
|
|
* the default value is not needed.
|
|
*
|
|
* @param nm property name.
|
|
* @param val default value.
|
|
* @return the {@code Long} value of the property.
|
|
* @throws SecurityException for the same reasons as
|
|
* {@link System#getProperty(String) System.getProperty}
|
|
* @see java.lang.System#getProperty(java.lang.String)
|
|
* @see java.lang.System#getProperty(java.lang.String, java.lang.String)
|
|
*/
|
|
public static Long getLong(String nm, long val) {
|
|
Long result = Long.getLong(nm, null);
|
|
return (result == null) ? Long.valueOf(val) : result;
|
|
}
|
|
|
|
/**
|
|
* Returns the {@code long} value of the system property with
|
|
* the specified name. The first argument is treated as the name
|
|
* of a system property. System properties are accessible through
|
|
* the {@link java.lang.System#getProperty(java.lang.String)}
|
|
* method. The string value of this property is then interpreted
|
|
* as a {@code long} value, as per the
|
|
* {@link Long#decode decode} method, and a {@code Long} object
|
|
* representing this value is returned; in summary:
|
|
*
|
|
* <ul>
|
|
* <li>If the property value begins with the two ASCII characters
|
|
* {@code 0x} or the ASCII character {@code #}, not followed by
|
|
* a minus sign, then the rest of it is parsed as a hexadecimal integer
|
|
* exactly as for the method {@link #valueOf(java.lang.String, int)}
|
|
* with radix 16.
|
|
* <li>If the property value begins with the ASCII character
|
|
* {@code 0} followed by another character, it is parsed as
|
|
* an octal integer exactly as by the method {@link
|
|
* #valueOf(java.lang.String, int)} with radix 8.
|
|
* <li>Otherwise the property value is parsed as a decimal
|
|
* integer exactly as by the method
|
|
* {@link #valueOf(java.lang.String, int)} with radix 10.
|
|
* </ul>
|
|
*
|
|
* <p>Note that, in every case, neither {@code L}
|
|
* ({@code '\u005Cu004C'}) nor {@code l}
|
|
* ({@code '\u005Cu006C'}) is permitted to appear at the end
|
|
* of the property value as a type indicator, as would be
|
|
* permitted in Java programming language source code.
|
|
*
|
|
* <p>The second argument is the default value. The default value is
|
|
* returned if there is no property of the specified name, if the
|
|
* property does not have the correct numeric format, or if the
|
|
* specified name is empty or {@code null}.
|
|
*
|
|
* @param nm property name.
|
|
* @param val default value.
|
|
* @return the {@code Long} value of the property.
|
|
* @throws SecurityException for the same reasons as
|
|
* {@link System#getProperty(String) System.getProperty}
|
|
* @see System#getProperty(java.lang.String)
|
|
* @see System#getProperty(java.lang.String, java.lang.String)
|
|
*/
|
|
public static Long getLong(String nm, Long val) {
|
|
String v = null;
|
|
try {
|
|
v = System.getProperty(nm);
|
|
} catch (IllegalArgumentException | NullPointerException e) {
|
|
}
|
|
if (v != null) {
|
|
try {
|
|
return Long.decode(v);
|
|
} catch (NumberFormatException e) {
|
|
}
|
|
}
|
|
return val;
|
|
}
|
|
|
|
/**
|
|
* Compares two {@code Long} objects numerically.
|
|
*
|
|
* @param anotherLong the {@code Long} to be compared.
|
|
* @return the value {@code 0} if this {@code Long} is
|
|
* equal to the argument {@code Long}; a value less than
|
|
* {@code 0} if this {@code Long} is numerically less
|
|
* than the argument {@code Long}; and a value greater
|
|
* than {@code 0} if this {@code Long} is numerically
|
|
* greater than the argument {@code Long} (signed
|
|
* comparison).
|
|
* @since 1.2
|
|
*/
|
|
public int compareTo(Long anotherLong) {
|
|
return compare(this.value, anotherLong.value);
|
|
}
|
|
|
|
/**
|
|
* Compares two {@code long} values numerically.
|
|
* The value returned is identical to what would be returned by:
|
|
* <pre>
|
|
* Long.valueOf(x).compareTo(Long.valueOf(y))
|
|
* </pre>
|
|
*
|
|
* @param x the first {@code long} to compare
|
|
* @param y the second {@code long} to compare
|
|
* @return the value {@code 0} if {@code x == y};
|
|
* a value less than {@code 0} if {@code x < y}; and
|
|
* a value greater than {@code 0} if {@code x > y}
|
|
* @since 1.7
|
|
*/
|
|
public static int compare(long x, long y) {
|
|
return (x < y) ? -1 : ((x == y) ? 0 : 1);
|
|
}
|
|
|
|
/**
|
|
* Compares two {@code long} values numerically treating the values
|
|
* as unsigned.
|
|
*
|
|
* @param x the first {@code long} to compare
|
|
* @param y the second {@code long} to compare
|
|
* @return the value {@code 0} if {@code x == y}; a value less
|
|
* than {@code 0} if {@code x < y} as unsigned values; and
|
|
* a value greater than {@code 0} if {@code x > y} as
|
|
* unsigned values
|
|
* @since 1.8
|
|
*/
|
|
public static int compareUnsigned(long x, long y) {
|
|
return compare(x + MIN_VALUE, y + MIN_VALUE);
|
|
}
|
|
|
|
|
|
/**
|
|
* Returns the unsigned quotient of dividing the first argument by
|
|
* the second where each argument and the result is interpreted as
|
|
* an unsigned value.
|
|
*
|
|
* <p>Note that in two's complement arithmetic, the three other
|
|
* basic arithmetic operations of add, subtract, and multiply are
|
|
* bit-wise identical if the two operands are regarded as both
|
|
* being signed or both being unsigned. Therefore separate {@code
|
|
* addUnsigned}, etc. methods are not provided.
|
|
*
|
|
* @param dividend the value to be divided
|
|
* @param divisor the value doing the dividing
|
|
* @return the unsigned quotient of the first argument divided by
|
|
* the second argument
|
|
* @see #remainderUnsigned
|
|
* @since 1.8
|
|
*/
|
|
public static long divideUnsigned(long dividend, long divisor) {
|
|
/* See Hacker's Delight (2nd ed), section 9.3 */
|
|
if (divisor >= 0) {
|
|
final long q = (dividend >>> 1) / divisor << 1;
|
|
final long r = dividend - q * divisor;
|
|
return q + ((r | ~(r - divisor)) >>> (Long.SIZE - 1));
|
|
}
|
|
return (dividend & ~(dividend - divisor)) >>> (Long.SIZE - 1);
|
|
}
|
|
|
|
/**
|
|
* Returns the unsigned remainder from dividing the first argument
|
|
* by the second where each argument and the result is interpreted
|
|
* as an unsigned value.
|
|
*
|
|
* @param dividend the value to be divided
|
|
* @param divisor the value doing the dividing
|
|
* @return the unsigned remainder of the first argument divided by
|
|
* the second argument
|
|
* @see #divideUnsigned
|
|
* @since 1.8
|
|
*/
|
|
public static long remainderUnsigned(long dividend, long divisor) {
|
|
/* See Hacker's Delight (2nd ed), section 9.3 */
|
|
if (divisor >= 0) {
|
|
final long q = (dividend >>> 1) / divisor << 1;
|
|
final long r = dividend - q * divisor;
|
|
/*
|
|
* Here, 0 <= r < 2 * divisor
|
|
* (1) When 0 <= r < divisor, the remainder is simply r.
|
|
* (2) Otherwise the remainder is r - divisor.
|
|
*
|
|
* In case (1), r - divisor < 0. Applying ~ produces a long with
|
|
* sign bit 0, so >> produces 0. The returned value is thus r.
|
|
*
|
|
* In case (2), a similar reasoning shows that >> produces -1,
|
|
* so the returned value is r - divisor.
|
|
*/
|
|
return r - ((~(r - divisor) >> (Long.SIZE - 1)) & divisor);
|
|
}
|
|
/*
|
|
* (1) When dividend >= 0, the remainder is dividend.
|
|
* (2) Otherwise
|
|
* (2.1) When dividend < divisor, the remainder is dividend.
|
|
* (2.2) Otherwise the remainder is dividend - divisor
|
|
*
|
|
* A reasoning similar to the above shows that the returned value
|
|
* is as expected.
|
|
*/
|
|
return dividend - (((dividend & ~(dividend - divisor)) >> (Long.SIZE - 1)) & divisor);
|
|
}
|
|
|
|
// Bit Twiddling
|
|
|
|
/**
|
|
* The number of bits used to represent a {@code long} value in two's
|
|
* complement binary form.
|
|
*
|
|
* @since 1.5
|
|
*/
|
|
@Native public static final int SIZE = 64;
|
|
|
|
/**
|
|
* The number of bytes used to represent a {@code long} value in two's
|
|
* complement binary form.
|
|
*
|
|
* @since 1.8
|
|
*/
|
|
public static final int BYTES = SIZE / Byte.SIZE;
|
|
|
|
/**
|
|
* Returns a {@code long} value with at most a single one-bit, in the
|
|
* position of the highest-order ("leftmost") one-bit in the specified
|
|
* {@code long} value. Returns zero if the specified value has no
|
|
* one-bits in its two's complement binary representation, that is, if it
|
|
* is equal to zero.
|
|
*
|
|
* @param i the value whose highest one bit is to be computed
|
|
* @return a {@code long} value with a single one-bit, in the position
|
|
* of the highest-order one-bit in the specified value, or zero if
|
|
* the specified value is itself equal to zero.
|
|
* @since 1.5
|
|
*/
|
|
public static long highestOneBit(long i) {
|
|
return i & (MIN_VALUE >>> numberOfLeadingZeros(i));
|
|
}
|
|
|
|
/**
|
|
* Returns a {@code long} value with at most a single one-bit, in the
|
|
* position of the lowest-order ("rightmost") one-bit in the specified
|
|
* {@code long} value. Returns zero if the specified value has no
|
|
* one-bits in its two's complement binary representation, that is, if it
|
|
* is equal to zero.
|
|
*
|
|
* @param i the value whose lowest one bit is to be computed
|
|
* @return a {@code long} value with a single one-bit, in the position
|
|
* of the lowest-order one-bit in the specified value, or zero if
|
|
* the specified value is itself equal to zero.
|
|
* @since 1.5
|
|
*/
|
|
public static long lowestOneBit(long i) {
|
|
// HD, Section 2-1
|
|
return i & -i;
|
|
}
|
|
|
|
/**
|
|
* Returns the number of zero bits preceding the highest-order
|
|
* ("leftmost") one-bit in the two's complement binary representation
|
|
* of the specified {@code long} value. Returns 64 if the
|
|
* specified value has no one-bits in its two's complement representation,
|
|
* in other words if it is equal to zero.
|
|
*
|
|
* <p>Note that this method is closely related to the logarithm base 2.
|
|
* For all positive {@code long} values x:
|
|
* <ul>
|
|
* <li>floor(log<sub>2</sub>(x)) = {@code 63 - numberOfLeadingZeros(x)}
|
|
* <li>ceil(log<sub>2</sub>(x)) = {@code 64 - numberOfLeadingZeros(x - 1)}
|
|
* </ul>
|
|
*
|
|
* @param i the value whose number of leading zeros is to be computed
|
|
* @return the number of zero bits preceding the highest-order
|
|
* ("leftmost") one-bit in the two's complement binary representation
|
|
* of the specified {@code long} value, or 64 if the value
|
|
* is equal to zero.
|
|
* @since 1.5
|
|
*/
|
|
@IntrinsicCandidate
|
|
public static int numberOfLeadingZeros(long i) {
|
|
int x = (int)(i >>> 32);
|
|
return x == 0 ? 32 + Integer.numberOfLeadingZeros((int)i)
|
|
: Integer.numberOfLeadingZeros(x);
|
|
}
|
|
|
|
/**
|
|
* Returns the number of zero bits following the lowest-order ("rightmost")
|
|
* one-bit in the two's complement binary representation of the specified
|
|
* {@code long} value. Returns 64 if the specified value has no
|
|
* one-bits in its two's complement representation, in other words if it is
|
|
* equal to zero.
|
|
*
|
|
* @param i the value whose number of trailing zeros is to be computed
|
|
* @return the number of zero bits following the lowest-order ("rightmost")
|
|
* one-bit in the two's complement binary representation of the
|
|
* specified {@code long} value, or 64 if the value is equal
|
|
* to zero.
|
|
* @since 1.5
|
|
*/
|
|
@IntrinsicCandidate
|
|
public static int numberOfTrailingZeros(long i) {
|
|
int x = (int)i;
|
|
return x == 0 ? 32 + Integer.numberOfTrailingZeros((int)(i >>> 32))
|
|
: Integer.numberOfTrailingZeros(x);
|
|
}
|
|
|
|
/**
|
|
* Returns the number of one-bits in the two's complement binary
|
|
* representation of the specified {@code long} value. This function is
|
|
* sometimes referred to as the <i>population count</i>.
|
|
*
|
|
* @param i the value whose bits are to be counted
|
|
* @return the number of one-bits in the two's complement binary
|
|
* representation of the specified {@code long} value.
|
|
* @since 1.5
|
|
*/
|
|
@IntrinsicCandidate
|
|
public static int bitCount(long i) {
|
|
// HD, Figure 5-2
|
|
i = i - ((i >>> 1) & 0x5555555555555555L);
|
|
i = (i & 0x3333333333333333L) + ((i >>> 2) & 0x3333333333333333L);
|
|
i = (i + (i >>> 4)) & 0x0f0f0f0f0f0f0f0fL;
|
|
i = i + (i >>> 8);
|
|
i = i + (i >>> 16);
|
|
i = i + (i >>> 32);
|
|
return (int)i & 0x7f;
|
|
}
|
|
|
|
/**
|
|
* Returns the value obtained by rotating the two's complement binary
|
|
* representation of the specified {@code long} value left by the
|
|
* specified number of bits. (Bits shifted out of the left hand, or
|
|
* high-order, side reenter on the right, or low-order.)
|
|
*
|
|
* <p>Note that left rotation with a negative distance is equivalent to
|
|
* right rotation: {@code rotateLeft(val, -distance) == rotateRight(val,
|
|
* distance)}. Note also that rotation by any multiple of 64 is a
|
|
* no-op, so all but the last six bits of the rotation distance can be
|
|
* ignored, even if the distance is negative: {@code rotateLeft(val,
|
|
* distance) == rotateLeft(val, distance & 0x3F)}.
|
|
*
|
|
* @param i the value whose bits are to be rotated left
|
|
* @param distance the number of bit positions to rotate left
|
|
* @return the value obtained by rotating the two's complement binary
|
|
* representation of the specified {@code long} value left by the
|
|
* specified number of bits.
|
|
* @since 1.5
|
|
*/
|
|
public static long rotateLeft(long i, int distance) {
|
|
return (i << distance) | (i >>> -distance);
|
|
}
|
|
|
|
/**
|
|
* Returns the value obtained by rotating the two's complement binary
|
|
* representation of the specified {@code long} value right by the
|
|
* specified number of bits. (Bits shifted out of the right hand, or
|
|
* low-order, side reenter on the left, or high-order.)
|
|
*
|
|
* <p>Note that right rotation with a negative distance is equivalent to
|
|
* left rotation: {@code rotateRight(val, -distance) == rotateLeft(val,
|
|
* distance)}. Note also that rotation by any multiple of 64 is a
|
|
* no-op, so all but the last six bits of the rotation distance can be
|
|
* ignored, even if the distance is negative: {@code rotateRight(val,
|
|
* distance) == rotateRight(val, distance & 0x3F)}.
|
|
*
|
|
* @param i the value whose bits are to be rotated right
|
|
* @param distance the number of bit positions to rotate right
|
|
* @return the value obtained by rotating the two's complement binary
|
|
* representation of the specified {@code long} value right by the
|
|
* specified number of bits.
|
|
* @since 1.5
|
|
*/
|
|
public static long rotateRight(long i, int distance) {
|
|
return (i >>> distance) | (i << -distance);
|
|
}
|
|
|
|
/**
|
|
* Returns the value obtained by reversing the order of the bits in the
|
|
* two's complement binary representation of the specified {@code long}
|
|
* value.
|
|
*
|
|
* @param i the value to be reversed
|
|
* @return the value obtained by reversing order of the bits in the
|
|
* specified {@code long} value.
|
|
* @since 1.5
|
|
*/
|
|
public static long reverse(long i) {
|
|
// HD, Figure 7-1
|
|
i = (i & 0x5555555555555555L) << 1 | (i >>> 1) & 0x5555555555555555L;
|
|
i = (i & 0x3333333333333333L) << 2 | (i >>> 2) & 0x3333333333333333L;
|
|
i = (i & 0x0f0f0f0f0f0f0f0fL) << 4 | (i >>> 4) & 0x0f0f0f0f0f0f0f0fL;
|
|
|
|
return reverseBytes(i);
|
|
}
|
|
|
|
/**
|
|
* Returns the signum function of the specified {@code long} value. (The
|
|
* return value is -1 if the specified value is negative; 0 if the
|
|
* specified value is zero; and 1 if the specified value is positive.)
|
|
*
|
|
* @param i the value whose signum is to be computed
|
|
* @return the signum function of the specified {@code long} value.
|
|
* @since 1.5
|
|
*/
|
|
public static int signum(long i) {
|
|
// HD, Section 2-7
|
|
return (int) ((i >> 63) | (-i >>> 63));
|
|
}
|
|
|
|
/**
|
|
* Returns the value obtained by reversing the order of the bytes in the
|
|
* two's complement representation of the specified {@code long} value.
|
|
*
|
|
* @param i the value whose bytes are to be reversed
|
|
* @return the value obtained by reversing the bytes in the specified
|
|
* {@code long} value.
|
|
* @since 1.5
|
|
*/
|
|
@IntrinsicCandidate
|
|
public static long reverseBytes(long i) {
|
|
i = (i & 0x00ff00ff00ff00ffL) << 8 | (i >>> 8) & 0x00ff00ff00ff00ffL;
|
|
return (i << 48) | ((i & 0xffff0000L) << 16) |
|
|
((i >>> 16) & 0xffff0000L) | (i >>> 48);
|
|
}
|
|
|
|
/**
|
|
* Adds two {@code long} values together as per the + operator.
|
|
*
|
|
* @param a the first operand
|
|
* @param b the second operand
|
|
* @return the sum of {@code a} and {@code b}
|
|
* @see java.util.function.BinaryOperator
|
|
* @since 1.8
|
|
*/
|
|
public static long sum(long a, long b) {
|
|
return a + b;
|
|
}
|
|
|
|
/**
|
|
* Returns the greater of two {@code long} values
|
|
* as if by calling {@link Math#max(long, long) Math.max}.
|
|
*
|
|
* @param a the first operand
|
|
* @param b the second operand
|
|
* @return the greater of {@code a} and {@code b}
|
|
* @see java.util.function.BinaryOperator
|
|
* @since 1.8
|
|
*/
|
|
public static long max(long a, long b) {
|
|
return Math.max(a, b);
|
|
}
|
|
|
|
/**
|
|
* Returns the smaller of two {@code long} values
|
|
* as if by calling {@link Math#min(long, long) Math.min}.
|
|
*
|
|
* @param a the first operand
|
|
* @param b the second operand
|
|
* @return the smaller of {@code a} and {@code b}
|
|
* @see java.util.function.BinaryOperator
|
|
* @since 1.8
|
|
*/
|
|
public static long min(long a, long b) {
|
|
return Math.min(a, b);
|
|
}
|
|
|
|
/**
|
|
* Returns an {@link Optional} containing the nominal descriptor for this
|
|
* instance, which is the instance itself.
|
|
*
|
|
* @return an {@link Optional} describing the {@linkplain Long} instance
|
|
* @since 12
|
|
* @hide
|
|
*/
|
|
@Override
|
|
public Optional<Long> describeConstable() {
|
|
return Optional.of(this);
|
|
}
|
|
|
|
/**
|
|
* Resolves this instance as a {@link ConstantDesc}, the result of which is
|
|
* the instance itself.
|
|
*
|
|
* @param lookup ignored
|
|
* @return the {@linkplain Long} instance
|
|
* @since 12
|
|
* @hide
|
|
*/
|
|
@Override
|
|
public Long resolveConstantDesc(MethodHandles.Lookup lookup) {
|
|
return this;
|
|
}
|
|
|
|
/** use serialVersionUID from JDK 1.0.2 for interoperability */
|
|
@java.io.Serial
|
|
@Native private static final long serialVersionUID = 4290774380558885855L;
|
|
}
|