/*
* CloseEncoder.java February 2007
*
* Copyright (C) 2007, Niall Gallagher <niallg@users.sf.net>
*
* Licensed 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.simpleframework.http.core;
import java.io.IOException;
import java.nio.ByteBuffer;
import org.simpleframework.transport.ByteWriter;
/**
* The <code>CloseEncoder</code> is used to close a connection once
* all of the content has been produced. This is typically used if
* the connected client supports the HTTP/1.0 protocol and there is
* no Connection header with the keep-alive token. For reasons of
* performance this should not be used for HTTP/1.1 clients.
*
* @author Niall Gallagher
*/
class CloseEncoder implements BodyEncoder {
/**
* This is the observer used to notify the selector of events.
*/
private final BodyObserver observer;
/**
* This is the underlying writer used to deliver the raw data.
*/
private final ByteWriter writer;
/**
* Constructor for the <code>CloseEncoder</code> object. This is
* used to create a producer that will close the underlying socket
* as a means to signal that the response is fully sent. This is
* typically used with HTTP/1.0 connections.
*
* @param writer this is used to send to the underlying transport
* @param observer this is used to deliver signals to the kernel
*/
public CloseEncoder(BodyObserver observer, ByteWriter writer) {
this.observer = observer;
this.writer = writer;
}
/**
* This method is used to encode the provided array of bytes in
* a HTTP/1.1 complaint format and sent it to the client. Once
* the data has been encoded it is handed to the transport layer
* within the server, which may choose to buffer the data if the
* content is too small to send efficiently or if the socket is
* not write ready.
*
* @param array this is the array of bytes to send to the client
*/
public void encode(byte[] array) throws IOException {
encode(array, 0, array.length);
}
/**
* This method is used to encode the provided array of bytes in
* a HTTP/1.1 complaint format and sent it to the client. Once
* the data has been encoded it is handed to the transport layer
* within the server, which may choose to buffer the data if the
* content is too small to send efficiently or if the socket is
* not write ready.
*
* @param array this is the array of bytes to send to the client
* @param off this is the offset within the array to send from
* @param len this is the number of bytes that are to be sent
*/
public void encode(byte[] array, int off, int len) throws IOException {
ByteBuffer buffer = ByteBuffer.wrap(array, off, len);
if(len > 0) {
encode(buffer);
}
}
/**
* This method is used to encode the provided buffer of bytes in
* a HTTP/1.1 compliant format and sent it to the client. Once
* the data has been encoded it is handed to the transport layer
* within the server, which may choose to buffer the data if the
* content is too small to send efficiently or if the socket is
* not write ready.
*
* @param buffer this is the buffer of bytes to send to the client
*/
public void encode(ByteBuffer buffer) throws IOException {
int mark = buffer.position();
int size = buffer.limit();
if(mark > size) {
throw new BodyEncoderException("Buffer position greater than limit");
}
encode(buffer, 0, size - mark);
}
/**
* This method is used to encode the provided buffer of bytes in
* a HTTP/1.1 compliant format and sent it to the client. Once
* the data has been encoded it is handed to the transport layer
* within the server, which may choose to buffer the data if the
* content is too small to send efficiently or if the socket is
* not write ready.
*
* @param buffer this is the buffer of bytes to send to the client
* @param off this is the offset within the buffer to send from
* @param len this is the number of bytes that are to be sent
*/
public void encode(ByteBuffer buffer, int off, int len) throws IOException {
if(observer.isClosed()) {
throw new BodyEncoderException("Stream has been closed");
}
try {
writer.write(buffer, off, len);
} catch(Exception cause) {
if(writer != null) {
observer.error(writer);
}
throw new BodyEncoderException("Error sending response", cause);
}
}
/**
* This method is used to flush the contents of the buffer to
* the client. This method will block until such time as all of
* the data has been sent to the client. If at any point there
* is an error sending the content an exception is thrown.
*/
public void flush() throws IOException {
try {
if(!observer.isClosed()) {
writer.flush();
}
} catch(Exception cause) {
if(writer != null) {
observer.error(writer);
}
throw new BodyEncoderException("Error sending response", cause);
}
}
/**
* This is used to signal to the producer that all content has
* been written and the user no longer needs to write. This will
* close the underlying transport which tells the client that
* all of the content has been sent over the connection.
*/
public void close() throws IOException {
try {
if(!observer.isClosed()) {
observer.close(writer);
writer.close();
}
} catch(Exception cause) {
if(writer != null) {
observer.error(writer);
}
throw new BodyEncoderException("Error sending response", cause);
}
}
}