EmptyByteBuf.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.buffer;

import static io.netty.util.internal.ObjectUtil.checkPositiveOrZero;

import io.netty.util.ByteProcessor;
import io.netty.util.internal.EmptyArrays;
import io.netty.util.internal.ObjectUtil;
import io.netty.util.internal.PlatformDependent;
import io.netty.util.internal.StringUtil;

import java.io.InputStream;
import java.io.OutputStream;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.ReadOnlyBufferException;
import java.nio.channels.FileChannel;
import java.nio.channels.GatheringByteChannel;
import java.nio.channels.ScatteringByteChannel;
import java.nio.charset.Charset;

/**
 * An empty {@link ByteBuf} whose capacity and maximum capacity are all {@code 0}.
 */
public final class EmptyByteBuf extends ByteBuf {

    static final int EMPTY_BYTE_BUF_HASH_CODE = 1;
    private static final ByteBuffer EMPTY_BYTE_BUFFER = ByteBuffer.allocateDirect(0);
    private static final long EMPTY_BYTE_BUFFER_ADDRESS;

    static {
        long emptyByteBufferAddress = 0;
        try {
            if (PlatformDependent.hasUnsafe()) {
                emptyByteBufferAddress = PlatformDependent.directBufferAddress(EMPTY_BYTE_BUFFER);
            }
        } catch (Throwable t) {
            // Ignore
        }
        EMPTY_BYTE_BUFFER_ADDRESS = emptyByteBufferAddress;
    }

    private final ByteBufAllocator alloc;
    private final ByteOrder order;
    private final String str;
// ... (1009 more lines)