/**
* Copyright 2010 JBoss Inc
*
* 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.eclipse.webdav.http.client;
import java.io.*;
import org.eclipse.webdav.IContext;
import org.eclipse.webdav.client.Policy;
import org.eclipse.webdav.client.WebDAVFactory;
import org.eclipse.webdav.internal.kernel.utils.Assert;
/**
* A common superclass for HTTP messages. There are two kinds of HTTP
* message; requests and responses. They both have in common a context
* and an input stream. This class factors out these similarities.
* <p>
* <b>Note:</b> This class/interface is part of an interim API that is still under
* development and expected to change significantly before reaching stability.
* It is being made available at this early stage to solicit feedback from pioneering
* adopters on the understanding that any code that uses this API will almost
* certainly be broken (repeatedly) as the API evolves.
* </p>
*/
public abstract class Message {
protected static BufferPool bufferPool = new BufferPool();
protected InputStream is;
protected boolean inputRead = false;
protected boolean hasInputStream = false;
protected IContext context;
/**
* Creates a message.
*
* @param context the message header, or <code>null</code> for an empty
* header
* @param is an input stream containing the message's body, or
* <code>null</code> for an empty body
*/
public Message(IContext context, InputStream is) {
this.context = context;
if (context == null)
this.context = WebDAVFactory.contextFactory.newContext();
this.is = is;
if (is == null)
this.is = new ByteArrayInputStream(new byte[0]);
}
/**
* Closes this message to free up any system resources. All messages
* must be closed before finalization.
*
* @exception IOException if there is an I/O error
*/
public void close() throws IOException {
is.close();
}
/**
* Returns the content length of this message's body, or -1 if the
* content length is unknown.
*
* @return the content length of this message's body
*/
public long getContentLength() {
long contentLength = context.getContentLength();
if (contentLength != -1)
return contentLength;
if (is instanceof ByteArrayInputStream)
return ((ByteArrayInputStream) is).available();
return -1;
}
/**
* Returns this message's context.
*
* @return this message's context
*/
public IContext getContext() {
return context;
}
/**
* Returns this message's input stream.
*
* @return this message's input stream
*/
public InputStream getInputStream() {
hasInputStream = true;
return is;
}
public String toString() {
return context.toString();
}
/**
* Writes this messages body to the given output stream. This method may
* only be called once during the lifetime of this message.
*
* @param os an output stream
* @exception IOException if there is an I/O error
*/
public void write(OutputStream os) throws IOException {
Assert.isTrue(!inputRead);
Assert.isTrue(!hasInputStream);
int bytesRead = 0;
int totalBytesRead = 0;
byte[] buffer = bufferPool.getBuffer();
long contentLength = getContentLength();
try {
while (bytesRead != -1 && (contentLength == -1 || contentLength > totalBytesRead)) {
if (contentLength == -1) {
bytesRead = is.read(buffer);
} else {
bytesRead = is.read(buffer, 0, (int) Math.min(buffer.length, contentLength - totalBytesRead));
}
if (bytesRead == -1) {
if (contentLength >= 0) {
throw new IOException(Policy.bind("exception.unexpectedEndStream")); //$NON-NLS-1$
}
} else {
totalBytesRead += bytesRead;
os.write(buffer, 0, bytesRead);
}
}
} finally {
bufferPool.putBuffer(buffer);
inputRead = true;
}
}
}