org.apache.mina.filter.codec.textline.TextLineEncoder 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.
*
*/
package org.apache.mina.filter.codec.textline;
import java.nio.charset.Charset;
import java.nio.charset.CharsetEncoder;
import org.apache.mina.core.buffer.IoBuffer;
import org.apache.mina.core.session.AttributeKey;
import org.apache.mina.core.session.IoSession;
import org.apache.mina.filter.codec.ProtocolEncoder;
import org.apache.mina.filter.codec.ProtocolEncoderAdapter;
import org.apache.mina.filter.codec.ProtocolEncoderOutput;
/**
* A {@link ProtocolEncoder} which encodes a string into a text line
* which ends with the delimiter.
*
* @author Apache MINA Project
*/
public class TextLineEncoder extends ProtocolEncoderAdapter {
private static final AttributeKey ENCODER = new AttributeKey(TextLineEncoder.class, "encoder");
private final Charset charset;
private final LineDelimiter delimiter;
private int maxLineLength = Integer.MAX_VALUE;
/**
* Creates a new instance with the current default {@link Charset}
* and {@link LineDelimiter#UNIX} delimiter.
*/
public TextLineEncoder() {
this(Charset.defaultCharset(), LineDelimiter.UNIX);
}
/**
* Creates a new instance with the current default {@link Charset}
* and the specified delimiter.
*
* @param delimiter The line delimiter to use
*/
public TextLineEncoder(String delimiter) {
this(new LineDelimiter(delimiter));
}
/**
* Creates a new instance with the current default {@link Charset}
* and the specified delimiter.
*
* @param delimiter The line delimiter to use
*/
public TextLineEncoder(LineDelimiter delimiter) {
this(Charset.defaultCharset(), delimiter);
}
/**
* Creates a new instance with the specified charset
* and {@link LineDelimiter#UNIX} delimiter.
*
* @param charset The {@link Charset} to use
*/
public TextLineEncoder(Charset charset) {
this(charset, LineDelimiter.UNIX);
}
/**
* Creates a new instance with the specified charset
* and the specified delimiter.
*
* @param charset The {@link Charset} to use
* @param delimiter The line delimiter to use
*/
public TextLineEncoder(Charset charset, String delimiter) {
this(charset, new LineDelimiter(delimiter));
}
/**
* Creates a new instance with the specified charset
* and the specified delimiter.
*
* @param charset The {@link Charset} to use
* @param delimiter The line delimiter to use
*/
public TextLineEncoder(Charset charset, LineDelimiter delimiter) {
if (charset == null) {
throw new IllegalArgumentException("charset");
}
if (delimiter == null) {
throw new IllegalArgumentException("delimiter");
}
if (LineDelimiter.AUTO.equals(delimiter)) {
throw new IllegalArgumentException("AUTO delimiter is not allowed for encoder.");
}
this.charset = charset;
this.delimiter = delimiter;
}
/**
* @return the allowed maximum size of the encoded line.
* If the size of the encoded line exceeds this value, the encoder
* will throw a {@link IllegalArgumentException}. The default value
* is {@link Integer#MAX_VALUE}.
*/
public int getMaxLineLength() {
return maxLineLength;
}
/**
* Sets the allowed maximum size of the encoded line.
* If the size of the encoded line exceeds this value, the encoder
* will throw a {@link IllegalArgumentException}. The default value
* is {@link Integer#MAX_VALUE}.
*
* @param maxLineLength The maximum line length
*/
public void setMaxLineLength(int maxLineLength) {
if (maxLineLength <= 0) {
throw new IllegalArgumentException("maxLineLength: " + maxLineLength);
}
this.maxLineLength = maxLineLength;
}
/**
* {@inheritDoc}
*/
@Override
public void encode(IoSession session, Object message, ProtocolEncoderOutput out) throws Exception {
CharsetEncoder encoder = (CharsetEncoder) session.getAttribute(ENCODER);
if (encoder == null) {
encoder = charset.newEncoder();
session.setAttribute(ENCODER, encoder);
}
String value = message == null ? "" : message.toString();
IoBuffer buf = IoBuffer.allocate(value.length()).setAutoExpand(true);
buf.putString(value, encoder);
if (buf.position() > maxLineLength) {
throw new IllegalArgumentException("Line length: " + buf.position());
}
buf.putString(delimiter.getValue(), encoder);
buf.flip();
out.write(buf);
}
/**
* Dispose the encoder
*
* @throws Exception If the dispose failed
*/
public void dispose() throws Exception {
// Do nothing
}
}