001    /*
002     * Copyright (c) 2007-2014 Concurrent, Inc. All Rights Reserved.
003     *
004     * Project and contact information: http://www.cascading.org/
005     *
006     * This file is part of the Cascading project.
007     *
008     * Licensed under the Apache License, Version 2.0 (the "License");
009     * you may not use this file except in compliance with the License.
010     * You may obtain a copy of the License at
011     *
012     *     http://www.apache.org/licenses/LICENSE-2.0
013     *
014     * Unless required by applicable law or agreed to in writing, software
015     * distributed under the License is distributed on an "AS IS" BASIS,
016     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
017     * See the License for the specific language governing permissions and
018     * limitations under the License.
019     */
020    
021    package cascading.scheme;
022    
023    import cascading.tuple.TupleEntry;
024    
025    /**
026     * SinkCall provides access to the current {@link Scheme#sink(cascading.flow.FlowProcess, SinkCall)} invocation
027     * arguments.
028     * <p/>
029     * Use the Context to store thread local values.
030     *
031     * @param <Context>
032     * @param <Output>
033     */
034    public interface SinkCall<Context, Output>
035      {
036      /**
037       * Method getContext returns the context of this SinkCall object.
038       *
039       * @return the context (type C) of this SinkCall object.
040       */
041      Context getContext();
042    
043      /**
044       * Method setContext sets the context of this SinkCall object.
045       *
046       * @param context the context of this SinkCall object.
047       */
048      void setContext( Context context );
049    
050      /**
051       * Method getOutgoingEntry returns the final {@link TupleEntry} to be passed to the
052       * {@link #getOutput()} output handler.
053       * <p/>
054       * That is, the result of calling getOutgoingEntry() should be passed directly to the
055       * platform specific output handler returned by getOutput().
056       * <p/>
057       * Note the returned value from this method cannot be modified.
058       *
059       * @return TupleEntry
060       */
061      TupleEntry getOutgoingEntry();
062    
063      Output getOutput();
064      }