78 lines
2.6 KiB
Java
78 lines
2.6 KiB
Java
/*
|
|
* Copyright 2017 The Android Open Source Project
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
package android.app.servertransaction;
|
|
|
|
import java.util.ArrayList;
|
|
import java.util.HashMap;
|
|
import java.util.Map;
|
|
|
|
/**
|
|
* An object pool that can provide reused objects if available.
|
|
* @hide
|
|
*/
|
|
class ObjectPool {
|
|
|
|
private static final Object sPoolSync = new Object();
|
|
private static final Map<Class, ArrayList<? extends ObjectPoolItem>> sPoolMap =
|
|
new HashMap<>();
|
|
|
|
private static final int MAX_POOL_SIZE = 50;
|
|
|
|
/**
|
|
* Obtain an instance of a specific class from the pool
|
|
* @param itemClass The class of the object we're looking for.
|
|
* @return An instance or null if there is none.
|
|
*/
|
|
public static <T extends ObjectPoolItem> T obtain(Class<T> itemClass) {
|
|
synchronized (sPoolSync) {
|
|
@SuppressWarnings("unchecked")
|
|
final ArrayList<T> itemPool = (ArrayList<T>) sPoolMap.get(itemClass);
|
|
if (itemPool != null && !itemPool.isEmpty()) {
|
|
return itemPool.remove(itemPool.size() - 1);
|
|
}
|
|
return null;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Recycle the object to the pool. The object should be properly cleared before this.
|
|
* @param item The object to recycle.
|
|
* @see ObjectPoolItem#recycle()
|
|
*/
|
|
public static <T extends ObjectPoolItem> void recycle(T item) {
|
|
synchronized (sPoolSync) {
|
|
@SuppressWarnings("unchecked")
|
|
ArrayList<T> itemPool = (ArrayList<T>) sPoolMap.get(item.getClass());
|
|
if (itemPool == null) {
|
|
itemPool = new ArrayList<>();
|
|
sPoolMap.put(item.getClass(), itemPool);
|
|
}
|
|
// Check if the item is already in the pool
|
|
final int size = itemPool.size();
|
|
for (int i = 0; i < size; i++) {
|
|
if (itemPool.get(i) == item) {
|
|
throw new IllegalStateException("Trying to recycle already recycled item");
|
|
}
|
|
}
|
|
|
|
if (size < MAX_POOL_SIZE) {
|
|
itemPool.add(item);
|
|
}
|
|
}
|
|
}
|
|
}
|