org.apache.mina.handler.stream.StreamIoHandler 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.handler.stream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.SocketTimeoutException;
import org.apache.mina.core.buffer.IoBuffer;
import org.apache.mina.core.service.IoHandler;
import org.apache.mina.core.service.IoHandlerAdapter;
import org.apache.mina.core.session.AttributeKey;
import org.apache.mina.core.session.IdleStatus;
import org.apache.mina.core.session.IoSession;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* A {@link IoHandler} that adapts asynchronous MINA events to stream I/O.
*
* Please extend this class and implement
* processStreamIo(IoSession, InputStream, OutputStream) to
* execute your stream I/O logic; please note that you must forward
* the process request to other thread or thread pool.
*
* @author Apache MINA Project
*/
public abstract class StreamIoHandler extends IoHandlerAdapter {
private final static Logger LOGGER = LoggerFactory.getLogger(StreamIoHandler.class);
private static final AttributeKey KEY_IN = new AttributeKey(StreamIoHandler.class, "in");
private static final AttributeKey KEY_OUT = new AttributeKey(StreamIoHandler.class, "out");
private int readTimeout;
private int writeTimeout;
protected StreamIoHandler() {
// Do nothing
}
/**
* Implement this method to execute your stream I/O logic;
* please note that you must forward the process request to other
* thread or thread pool.
*
* @param session The current session
* @param in The input stream
* @param out The output stream
*/
protected abstract void processStreamIo(IoSession session, InputStream in, OutputStream out);
/**
* @return read timeout in seconds.
* The default value is 0 (disabled).
*/
public int getReadTimeout() {
return readTimeout;
}
/**
* Sets read timeout in seconds.
* The default value is 0 (disabled).
* @param readTimeout The Read timeout
*/
public void setReadTimeout(int readTimeout) {
this.readTimeout = readTimeout;
}
/**
* @return write timeout in seconds.
* The default value is 0 (disabled).
*/
public int getWriteTimeout() {
return writeTimeout;
}
/**
* Sets write timeout in seconds.
* The default value is 0 (disabled).
*
* @param writeTimeout The Write timeout
*/
public void setWriteTimeout(int writeTimeout) {
this.writeTimeout = writeTimeout;
}
/**
* Initializes streams and timeout settings.
*/
@Override
public void sessionOpened(IoSession session) {
// Set timeouts
session.getConfig().setWriteTimeout(writeTimeout);
session.getConfig().setIdleTime(IdleStatus.READER_IDLE, readTimeout);
// Create streams
InputStream in = new IoSessionInputStream();
OutputStream out = new IoSessionOutputStream(session);
session.setAttribute(KEY_IN, in);
session.setAttribute(KEY_OUT, out);
processStreamIo(session, in, out);
}
/**
* Closes streams
*/
@Override
public void sessionClosed(IoSession session) throws Exception {
final InputStream in = (InputStream) session.getAttribute(KEY_IN);
final OutputStream out = (OutputStream) session.getAttribute(KEY_OUT);
try {
in.close();
} finally {
out.close();
}
}
/**
* Forwards read data to input stream.
*/
@Override
public void messageReceived(IoSession session, Object buf) {
final IoSessionInputStream in = (IoSessionInputStream) session.getAttribute(KEY_IN);
in.write((IoBuffer) buf);
}
/**
* Forwards caught exceptions to input stream.
*/
@Override
public void exceptionCaught(IoSession session, Throwable cause) {
final IoSessionInputStream in = (IoSessionInputStream) session.getAttribute(KEY_IN);
IOException e = null;
if (cause instanceof StreamIoException) {
e = (IOException) cause.getCause();
} else if (cause instanceof IOException) {
e = (IOException) cause;
}
if (e != null && in != null) {
in.throwException(e);
} else {
LOGGER.warn("Unexpected exception.", cause);
session.closeNow();
}
}
/**
* Handles read timeout.
*/
@Override
public void sessionIdle(IoSession session, IdleStatus status) {
if (status == IdleStatus.READER_IDLE) {
throw new StreamIoException(new SocketTimeoutException("Read timeout"));
}
}
private static class StreamIoException extends RuntimeException {
private static final long serialVersionUID = 3976736960742503222L;
public StreamIoException(IOException cause) {
super(cause);
}
}
}