io.netty.buffer.ByteBufOutputStream Maven / Gradle / Ivy
/*
* 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:
*
* 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 io.netty.util.CharsetUtil;
import io.netty.util.internal.ObjectUtil;
import java.io.DataOutput;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.OutputStream;
/**
* An {@link OutputStream} which writes data to a {@link ByteBuf}.
*
* A write operation against this stream will occur at the {@code writerIndex}
* of its underlying buffer and the {@code writerIndex} will increase during
* the write operation.
*
* This stream implements {@link DataOutput} for your convenience.
* The endianness of the stream is not always big endian but depends on
* the endianness of the underlying buffer.
*
* @see ByteBufInputStream
*/
public class ByteBufOutputStream extends OutputStream implements DataOutput {
private final ByteBuf buffer;
private final int startIndex;
private DataOutputStream utf8out; // lazily-instantiated
private boolean closed;
private final boolean releaseOnClose;
/**
* Creates a new stream which writes data to the specified {@code buffer}.
*/
public ByteBufOutputStream(ByteBuf buffer) {
this(buffer, false);
}
/**
* Creates a new stream which writes data to the specified {@code buffer}.
*
* @param buffer Writes data to the buffer for this {@link OutputStream}.
* @param releaseOnClose {@code true} means that when {@link #close()} is called then {@link ByteBuf#release()} will
* be called on {@code buffer}.
*/
public ByteBufOutputStream(ByteBuf buffer, boolean releaseOnClose) {
this.releaseOnClose = releaseOnClose;
this.buffer = ObjectUtil.checkNotNull(buffer, "buffer");
startIndex = buffer.writerIndex();
}
/**
* Returns the number of written bytes by this stream so far.
*/
public int writtenBytes() {
return buffer.writerIndex() - startIndex;
}
@Override
public void write(byte[] b, int off, int len) throws IOException {
if (len == 0) {
return;
}
buffer.writeBytes(b, off, len);
}
@Override
public void write(byte[] b) throws IOException {
buffer.writeBytes(b);
}
@Override
public void write(int b) throws IOException {
buffer.writeByte(b);
}
@Override
public void writeBoolean(boolean v) throws IOException {
buffer.writeBoolean(v);
}
@Override
public void writeByte(int v) throws IOException {
buffer.writeByte(v);
}
@Override
public void writeBytes(String s) throws IOException {
buffer.writeCharSequence(s, CharsetUtil.US_ASCII);
}
@Override
public void writeChar(int v) throws IOException {
buffer.writeChar(v);
}
@Override
public void writeChars(String s) throws IOException {
int len = s.length();
for (int i = 0; i < len; i++) {
buffer.writeChar(s.charAt(i));
}
}
@Override
public void writeDouble(double v) throws IOException {
buffer.writeDouble(v);
}
@Override
public void writeFloat(float v) throws IOException {
buffer.writeFloat(v);
}
@Override
public void writeInt(int v) throws IOException {
buffer.writeInt(v);
}
@Override
public void writeLong(long v) throws IOException {
buffer.writeLong(v);
}
@Override
public void writeShort(int v) throws IOException {
buffer.writeShort((short) v);
}
@Override
public void writeUTF(String s) throws IOException {
DataOutputStream out = utf8out;
if (out == null) {
if (closed) {
throw new IOException("The stream is closed");
}
// Suppress a warning since the stream is closed in the close() method
utf8out = out = new DataOutputStream(this);
}
out.writeUTF(s);
}
/**
* Returns the buffer where this stream is writing data.
*/
public ByteBuf buffer() {
return buffer;
}
@Override
public void close() throws IOException {
if (closed) {
return;
}
closed = true;
try {
super.close();
} finally {
if (utf8out != null) {
utf8out.close();
}
if (releaseOnClose) {
buffer.release();
}
}
}
}