/**
* Copyright 2005-2011 Noelios Technologies.
*
* The contents of this file are subject to the terms of one of the following
* open source licenses: LGPL 3.0 or LGPL 2.1 or CDDL 1.0 or EPL 1.0 (the
* "Licenses"). You can select the license that you prefer but you may not use
* this file except in compliance with one of these Licenses.
*
* You can obtain a copy of the LGPL 3.0 license at
* http://www.opensource.org/licenses/lgpl-3.0.html
*
* You can obtain a copy of the LGPL 2.1 license at
* http://www.opensource.org/licenses/lgpl-2.1.php
*
* You can obtain a copy of the CDDL 1.0 license at
* http://www.opensource.org/licenses/cddl1.php
*
* You can obtain a copy of the EPL 1.0 license at
* http://www.opensource.org/licenses/eclipse-1.0.php
*
* See the Licenses for the specific language governing permissions and
* limitations under the Licenses.
*
* Alternatively, you can obtain a royalty free commercial license with less
* limitations, transferable or non-transferable, directly at
* http://www.noelios.com/products/restlet-engine
*
* Restlet is a registered trademark of Noelios Technologies.
*/
package org.restlet.engine.application;
import java.util.Iterator;
import org.restlet.Context;
import org.restlet.Request;
import org.restlet.Response;
import org.restlet.data.Encoding;
import org.restlet.representation.Representation;
import org.restlet.routing.Filter;
// [excludes gwt]
/**
* Filter uncompressing entities.
*
* Concurrency note: instances of this class or its subclasses can be invoked by
* several threads at the same time and therefore must be thread-safe. You
* should be especially careful when storing state in member variables.
*
* @author Jerome Louvel
*/
public class Decoder extends Filter {
/**
* Indicates if the request entity should be decoded.
*/
private final boolean decodingRequest;
/**
* Indicates if the response entity should be decoded.
*/
private final boolean decodingResponse;
/**
* Constructor to only decode request entities before handling.
*
* @param context
* The context.
*/
public Decoder(Context context) {
this(context, true, false);
}
/**
* Constructor.
*
* @param context
* The context.
* @param decodingRequest
* Indicates if the request entity should be decoded.
* @param decodingResponse
* Indicates if the response entity should be decoded.
*/
public Decoder(Context context, boolean decodingRequest,
boolean decodingResponse) {
super(context);
this.decodingRequest = decodingRequest;
this.decodingResponse = decodingResponse;
}
/**
* Allows filtering after its handling by the target Restlet. Does nothing
* by default.
*
* @param request
* The request to filter.
* @param response
* The response to filter.
*/
@Override
public void afterHandle(Request request, Response response) {
// Check if decoding of the response entity is needed
if (isDecodingResponse() && canDecode(response.getEntity())) {
response.setEntity(decode(response.getEntity()));
}
}
/**
* Allows filtering before its handling by the target Restlet. Does nothing
* by default.
*
* @param request
* The request to filter.
* @param response
* The response to filter.
* @return The continuation status.
*/
@Override
public int beforeHandle(Request request, Response response) {
// Check if decoding of the request entity is needed
if (isDecodingRequest() && canDecode(request.getEntity())) {
request.setEntity(decode(request.getEntity()));
}
return CONTINUE;
}
/**
* Indicates if a representation can be decoded.
*
* @param representation
* The representation to test.
* @return True if the call can be decoded.
*/
public boolean canDecode(Representation representation) {
// Test the existence of the representation and that at least an
// encoding applies.
boolean result = (representation != null)
&& (!representation.getEncodings().isEmpty());
if (result) {
boolean found = false;
for (final Iterator<Encoding> iter = representation.getEncodings()
.iterator(); !found && iter.hasNext();) {
found = (!iter.next().equals(Encoding.IDENTITY));
}
result = found;
}
return result;
}
/**
* Decodes a given representation if its encodings are supported by NRE.
*
* @param representation
* The representation to encode.
* @return The decoded representation or the original one if the encoding
* isn't supported by NRE.
*/
public Representation decode(Representation representation) {
Representation result = representation;
// Check if all encodings of the representation are supported in order
// to avoid the creation of a useless decodeRepresentation object.
// False if an encoding is not supported
boolean supported = true;
// True if all representation's encodings are IDENTITY
boolean identityEncodings = true;
for (final Iterator<Encoding> iter = representation.getEncodings()
.iterator(); supported && iter.hasNext();) {
final Encoding encoding = iter.next();
supported = DecodeRepresentation.getSupportedEncodings().contains(
encoding);
identityEncodings &= encoding.equals(Encoding.IDENTITY);
}
if (supported && !identityEncodings) {
result = new DecodeRepresentation(representation);
}
return result;
}
/**
* Indicates if the request entity should be decoded.
*
* @return True if the request entity should be decoded.
*/
public boolean isDecodingRequest() {
return this.decodingRequest;
}
/**
* Indicates if the response entity should be decoded.
*
* @return True if the response entity should be decoded.
*/
public boolean isDecodingResponse() {
return this.decodingResponse;
}
}