001    /**
002     * Copyright (C) 2009-2011 the original author or authors.
003     * See the notice.md file distributed with this work for additional
004     * information regarding copyright ownership.
005     *
006     * Licensed under the Apache License, Version 2.0 (the "License");
007     * you may not use this file except in compliance with the License.
008     * You may obtain a copy of the License at
009     *
010     *     http://www.apache.org/licenses/LICENSE-2.0
011     *
012     * Unless required by applicable law or agreed to in writing, software
013     * distributed under the License is distributed on an "AS IS" BASIS,
014     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015     * See the License for the specific language governing permissions and
016     * limitations under the License.
017     */
018    
019    package org.fusesource.restygwt.client.callback;
020    
021    import org.fusesource.restygwt.client.Method;
022    
023    import com.google.gwt.http.client.RequestCallback;
024    import com.google.gwt.http.client.Response;
025    
026    public interface CallbackFilter {
027    
028        /**
029         * main filter method for a callbackfilter.
030         *
031         * pattern is a chain of responsibility. in contrast to dispatcherfilter,
032         * each callbackfilter will be called for sure. this comes due to the fact
033         * that a dispatcherfilter might want to stop a request (e.g. by caching).
034         * whereas a callbackfilter should not stop the processing of other callback-
035         * filters, there seems to be no good reason for doing this.
036         *
037         * @return continue chain or not
038         */
039        public RequestCallback filter(final Method method, final Response response,
040                RequestCallback callback);
041    
042    }