/**
* Copyright 2012 LiveRamp
*
* 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 com.liveramp.cascading_ext.assembly;
import cascading.pipe.CoGroup;
import cascading.pipe.Every;
import cascading.pipe.Pipe;
import cascading.pipe.SubAssembly;
import cascading.pipe.assembly.Retain;
import cascading.pipe.joiner.BufferJoin;
import cascading.tuple.Fields;
import com.liveramp.cascading_ext.multi_group_by.MultiBuffer;
import com.liveramp.cascading_ext.multi_group_by.MultiBufferOperation;
import org.apache.log4j.Logger;
import java.util.Arrays;
public class MultiGroupBy extends SubAssembly {
private static final Logger LOG = Logger.getLogger(MultiGroupBy.class);
public MultiGroupBy(Pipe p0, Pipe p1, Fields groupFields, MultiBuffer operation) {
Pipe[] pipes = new Pipe[]{p0, p1};
Fields[] fields = new Fields[]{groupFields, groupFields};
init(pipes, fields, groupFields, operation);
}
public MultiGroupBy(Pipe p0, Fields group0, Pipe p1, Fields group1, Fields groupRename, MultiBuffer operation) {
Pipe[] pipes = new Pipe[]{p0, p1};
Fields[] fields = new Fields[]{group0, group1};
init(pipes, fields, groupRename, operation);
}
public MultiGroupBy(Pipe[] pipes, Fields groupFields, MultiBuffer operation) {
Fields[] allGroups = new Fields[pipes.length];
Arrays.fill(allGroups, groupFields);
init(pipes, allGroups, groupFields, operation);
}
public MultiGroupBy(Pipe[] pipes, Fields[] groupFields, Fields groupingRename, MultiBuffer operation) {
init(pipes, groupFields, groupingRename, operation);
}
/**
* Do not use -- all input fields no longer need to be specified, so "allFields" argument is ignored
*/
@Deprecated
public MultiGroupBy(Pipe[] pipes, Fields[] allFields, Fields[] groupFields, Fields groupingRename, MultiBuffer operation) {
init(pipes, groupFields, groupingRename, operation);
}
protected void init(Pipe[] pipes, Fields[] groupFields, Fields groupRename, MultiBuffer operation) {
Fields outputFields = groupRename.append(operation.getResultFields());
Pipe grouped = new CoGroup(pipes, groupFields, null, null, new BufferJoin());
grouped = new Every(grouped,
new MultiBufferOperation(groupRename, operation),
outputFields
);
grouped = new Retain(grouped,
outputFields
);
setTails(grouped);
}
}