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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * Copyright 2012 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:
 *
 *   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 io.netty.buffer;

import io.netty.util.Recycler;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;

abstract class PooledByteBuf extends AbstractReferenceCountedByteBuf {

    private final Recycler.Handle recyclerHandle;

    protected PoolChunk chunk;
    protected long handle;
    protected T memory;
    protected int offset;
    protected int length;
    int maxLength;
    Thread initThread;
    private ByteBuffer tmpNioBuf;

    protected PooledByteBuf(Recycler.Handle recyclerHandle, int maxCapacity) {
        super(maxCapacity);
        this.recyclerHandle = recyclerHandle;
    }

    void init(PoolChunk chunk, long handle, int offset, int length, int maxLength) {
        assert handle >= 0;
        assert chunk != null;

        this.chunk = chunk;
        this.handle = handle;
        memory = chunk.memory;
        this.offset = offset;
        this.length = length;
        this.maxLength = maxLength;
        setIndex(0, 0);
        tmpNioBuf = null;
        initThread = Thread.currentThread();
    }

    void initUnpooled(PoolChunk chunk, int length) {
        assert chunk != null;

        this.chunk = chunk;
        handle = 0;
        memory = chunk.memory;
        offset = 0;
        this.length = maxLength = length;
        setIndex(0, 0);
        tmpNioBuf = null;
        initThread = Thread.currentThread();
    }

    @Override
    public final int capacity() {
        return length;
    }

    @Override
    public final ByteBuf capacity(int newCapacity) {
        ensureAccessible();

        // If the request capacity does not require reallocation, just update the length of the memory.
        if (chunk.unpooled) {
            if (newCapacity == length) {
                return this;
            }
        } else {
            if (newCapacity > length) {
                if (newCapacity <= maxLength) {
                    length = newCapacity;
                    return this;
                }
            } else if (newCapacity < length) {
                if (newCapacity > maxLength >>> 1) {
                    if (maxLength <= 512) {
                        if (newCapacity > maxLength - 16) {
                            length = newCapacity;
                            setIndex(Math.min(readerIndex(), newCapacity), Math.min(writerIndex(), newCapacity));
                            return this;
                        }
                    } else { // > 512 (i.e. >= 1024)
                        length = newCapacity;
                        setIndex(Math.min(readerIndex(), newCapacity), Math.min(writerIndex(), newCapacity));
                        return this;
                    }
                }
            } else {
                return this;
            }
        }

        // Reallocation required.
        chunk.arena.reallocate(this, newCapacity, true);
        return this;
    }

    @Override
    public final ByteBufAllocator alloc() {
        return chunk.arena.parent;
    }

    @Override
    public final ByteOrder order() {
        return ByteOrder.BIG_ENDIAN;
    }

    @Override
    public final ByteBuf unwrap() {
        return null;
    }

    protected final ByteBuffer internalNioBuffer() {
        ByteBuffer tmpNioBuf = this.tmpNioBuf;
        if (tmpNioBuf == null) {
            this.tmpNioBuf = tmpNioBuf = newInternalNioBuffer(memory);
        }
        return tmpNioBuf;
    }

    protected abstract ByteBuffer newInternalNioBuffer(T memory);

    @Override
    protected final void deallocate() {
        if (handle >= 0) {
            final long handle = this.handle;
            this.handle = -1;
            memory = null;
            boolean sameThread = initThread == Thread.currentThread();
            initThread = null;
            chunk.arena.free(chunk, handle, maxLength, sameThread);
            recycle();
        }
    }

    private void recycle() {
        Recycler.Handle recyclerHandle = this.recyclerHandle;
        if (recyclerHandle != null) {
            ((Recycler) recycler()).recycle(this, recyclerHandle);
        }
    }

    protected abstract Recycler recycler();

    protected final int idx(int index) {
        return offset + index;
    }
}