79 lines
1.7 KiB
Java
79 lines
1.7 KiB
Java
package com.terraforged.core.util.concurrent;
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import java.util.ArrayList;
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import java.util.List;
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import java.util.function.Supplier;
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public class ObjectPool<T> {
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private final int capacity;
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private final List<Item<T>> pool;
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private final Supplier<? extends T> supplier;
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public ObjectPool(int size, Supplier<? extends T> supplier) {
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this.capacity = size;
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this.pool = new ArrayList<>(size);
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this.supplier = supplier;
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}
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public Item<T> get() {
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synchronized (pool) {
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if (pool.size() > 0) {
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return pool.remove(pool.size() - 1).retain();
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}
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}
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return new Item<>(supplier.get(), this);
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}
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public int size() {
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synchronized (pool) {
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return pool.size();
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}
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}
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private boolean restore(Item<T> item) {
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synchronized (pool) {
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int size = pool.size();
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if (size < capacity) {
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pool.add(item);
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return true;
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}
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}
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return false;
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}
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public static class Item<T> implements AutoCloseable {
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private final T value;
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private final ObjectPool<T> pool;
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private boolean released = false;
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private Item(T value, ObjectPool<T> pool) {
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this.value = value;
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this.pool = pool;
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}
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public T getValue() {
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return value;
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}
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public void release() {
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if (!released) {
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released = true;
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released = pool.restore(this);
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}
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}
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private Item<T> retain() {
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released = false;
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return this;
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}
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@Override
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public void close() {
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release();
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}
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}
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}
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