org.apache.http.impl.io.SessionOutputBufferImpl Maven / Gradle / Ivy
/*
* ====================================================================
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF 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.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
*
* {@link #writeLine(CharArrayBuffer)} and {@link #writeLine(String)} methods
* of this class use CR-LF as a line delimiter.
*
* @since 4.3
*/
public class SessionOutputBufferImpl implements SessionOutputBuffer, BufferInfo {
private static final byte[] CRLF = new byte[] {HTTP.CR, HTTP.LF};
private final HttpTransportMetricsImpl metrics;
private final ByteArrayBuffer buffer;
private final int fragementSizeHint;
private final CharsetEncoder encoder;
private OutputStream outStream;
private ByteBuffer bbuf;
/**
* Creates new instance of SessionOutputBufferImpl.
*
* @param metrics HTTP transport metrics.
* @param bufferSize buffer size. Must be a positive number.
* @param fragementSizeHint fragment size hint defining a minimal size of a fragment
* that should be written out directly to the socket bypassing the session buffer.
* Value {@code 0} disables fragment buffering.
* @param charEncoder charEncoder to be used for encoding HTTP protocol elements.
* If {@code null} simple type cast will be used for char to byte conversion.
*/
public SessionOutputBufferImpl(
final HttpTransportMetricsImpl metrics,
final int bufferSize,
final int fragementSizeHint,
final CharsetEncoder charEncoder) {
super();
Args.positive(bufferSize, "Buffer size");
Args.notNull(metrics, "HTTP transport metrcis");
this.metrics = metrics;
this.buffer = new ByteArrayBuffer(bufferSize);
this.fragementSizeHint = fragementSizeHint >= 0 ? fragementSizeHint : 0;
this.encoder = charEncoder;
}
public SessionOutputBufferImpl(
final HttpTransportMetricsImpl metrics,
final int bufferSize) {
this(metrics, bufferSize, bufferSize, null);
}
public void bind(final OutputStream outStream) {
this.outStream = outStream;
}
public boolean isBound() {
return this.outStream != null;
}
@Override
public int capacity() {
return this.buffer.capacity();
}
@Override
public int length() {
return this.buffer.length();
}
@Override
public int available() {
return capacity() - length();
}
private void streamWrite(final byte[] b, final int off, final int len) throws IOException {
Asserts.notNull(outStream, "Output stream");
this.outStream.write(b, off, len);
}
private void flushStream() throws IOException {
if (this.outStream != null) {
this.outStream.flush();
}
}
private void flushBuffer() throws IOException {
final int len = this.buffer.length();
if (len > 0) {
streamWrite(this.buffer.buffer(), 0, len);
this.buffer.clear();
this.metrics.incrementBytesTransferred(len);
}
}
@Override
public void flush() throws IOException {
flushBuffer();
flushStream();
}
@Override
public void write(final byte[] b, final int off, final int len) throws IOException {
if (b == null) {
return;
}
// Do not want to buffer large-ish chunks
// if the byte array is larger then MIN_CHUNK_LIMIT
// write it directly to the output stream
if (len > this.fragementSizeHint || len > this.buffer.capacity()) {
// flush the buffer
flushBuffer();
// write directly to the out stream
streamWrite(b, off, len);
this.metrics.incrementBytesTransferred(len);
} else {
// Do not let the buffer grow unnecessarily
final int freecapacity = this.buffer.capacity() - this.buffer.length();
if (len > freecapacity) {
// flush the buffer
flushBuffer();
}
// buffer
this.buffer.append(b, off, len);
}
}
@Override
public void write(final byte[] b) throws IOException {
if (b == null) {
return;
}
write(b, 0, b.length);
}
@Override
public void write(final int b) throws IOException {
if (this.fragementSizeHint > 0) {
if (this.buffer.isFull()) {
flushBuffer();
}
this.buffer.append(b);
} else {
flushBuffer();
this.outStream.write(b);
}
}
/**
* Writes characters from the specified string followed by a line delimiter
* to this session buffer.
*
* This method uses CR-LF as a line delimiter.
*
* @param s the line.
* @throws IOException if an I/O error occurs.
*/
@Override
public void writeLine(final String s) throws IOException {
if (s == null) {
return;
}
if (s.length() > 0) {
if (this.encoder == null) {
for (int i = 0; i < s.length(); i++) {
write(s.charAt(i));
}
} else {
final CharBuffer cbuf = CharBuffer.wrap(s);
writeEncoded(cbuf);
}
}
write(CRLF);
}
/**
* Writes characters from the specified char array followed by a line
* delimiter to this session buffer.
*
* This method uses CR-LF as a line delimiter.
*
* @param charbuffer the buffer containing chars of the line.
* @throws IOException if an I/O error occurs.
*/
@Override
public void writeLine(final CharArrayBuffer charbuffer) throws IOException {
if (charbuffer == null) {
return;
}
if (this.encoder == null) {
int off = 0;
int remaining = charbuffer.length();
while (remaining > 0) {
int chunk = this.buffer.capacity() - this.buffer.length();
chunk = Math.min(chunk, remaining);
if (chunk > 0) {
this.buffer.append(charbuffer, off, chunk);
}
if (this.buffer.isFull()) {
flushBuffer();
}
off += chunk;
remaining -= chunk;
}
} else {
final CharBuffer cbuf = CharBuffer.wrap(charbuffer.buffer(), 0, charbuffer.length());
writeEncoded(cbuf);
}
write(CRLF);
}
private void writeEncoded(final CharBuffer cbuf) throws IOException {
if (!cbuf.hasRemaining()) {
return;
}
if (this.bbuf == null) {
this.bbuf = ByteBuffer.allocate(1024);
}
this.encoder.reset();
while (cbuf.hasRemaining()) {
final CoderResult result = this.encoder.encode(cbuf, this.bbuf, true);
handleEncodingResult(result);
}
final CoderResult result = this.encoder.flush(this.bbuf);
handleEncodingResult(result);
this.bbuf.clear();
}
private void handleEncodingResult(final CoderResult result) throws IOException {
if (result.isError()) {
result.throwException();
}
this.bbuf.flip();
while (this.bbuf.hasRemaining()) {
write(this.bbuf.get());
}
this.bbuf.compact();
}
@Override
public HttpTransportMetrics getMetrics() {
return this.metrics;
}
}