Recycler.java — netty Source File

Source Code

/*
 * Copyright 2013 The Netty Project
 *
 * The Netty Project licenses this file to you 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:
 *
 *   https://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 io.netty.util;

import io.netty.util.concurrent.FastThreadLocal;
import io.netty.util.concurrent.FastThreadLocalThread;
import io.netty.util.internal.ObjectPool;
import io.netty.util.internal.PlatformDependent;
import io.netty.util.internal.SystemPropertyUtil;
import io.netty.util.internal.UnstableApi;
import io.netty.util.internal.logging.InternalLogger;
import io.netty.util.internal.logging.InternalLoggerFactory;
import org.jctools.queues.MessagePassingQueue;
import org.jetbrains.annotations.VisibleForTesting;

import java.util.ArrayDeque;
import java.util.Objects;
import java.util.Queue;
import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;

import static io.netty.util.internal.PlatformDependent.newFixedMpmcQueue;
import static io.netty.util.internal.PlatformDependent.newMpscQueue;
import static java.lang.Math.max;
import static java.lang.Math.min;

/**
 * Light-weight object pool based on a thread-local stack.
 *
 * @param <T> the type of the pooled object
 */
public abstract class Recycler<T> {
    private static final InternalLogger logger = InternalLoggerFactory.getInstance(Recycler.class);

    /**
     * We created this handle to avoid having more than 2 concrete implementations of {@link EnhancedHandle}
     * i.e. NOOP_HANDLE, {@link DefaultHandle} and the one used in the LocalPool.
     */
    private static final class LocalPoolHandle<T> extends EnhancedHandle<T> {
        private final UnguardedLocalPool<T> pool;

        private LocalPoolHandle(UnguardedLocalPool<T> pool) {
            this.pool = pool;
        }

        @Override
        public void recycle(T object) {
            UnguardedLocalPool<T> pool = this.pool;
// ... (670 more lines)