/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.pig.builtin;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.apache.pig.EvalFunc;
import org.apache.pig.FuncSpec;
import org.apache.pig.PigException;
import org.apache.pig.backend.executionengine.ExecException;
import org.apache.pig.data.DataByteArray;
import org.apache.pig.data.DataType;
import org.apache.pig.data.Tuple;
import org.apache.pig.impl.logicalLayer.FrontendException;
import org.apache.pig.impl.logicalLayer.schema.Schema;
/**
* Generates the concatenation of the first two fields of a tuple.
*/
public class CONCAT extends EvalFunc<DataByteArray> {
@Override
public DataByteArray exec(Tuple input) throws IOException {
try {
DataByteArray dba1 = (DataByteArray)input.get(0);
DataByteArray dba2 = (DataByteArray)input.get(1);
if(dba1 != null && dba2 != null) {
return new DataByteArray(dba1, dba2);
} else {
return null;
}
} catch (ExecException exp) {
throw exp;
} catch (Exception e) {
int errCode = 2106;
String msg = "Error while computing concat in " + this.getClass().getSimpleName();
throw new ExecException(msg, errCode, PigException.BUG, e);
}
}
@Override
public Schema outputSchema(Schema input) {
return new Schema(new Schema.FieldSchema(null, DataType.BYTEARRAY));
}
/* (non-Javadoc)
* @see org.apache.pig.EvalFunc#getArgToFuncMapping()
*/
@Override
public List<FuncSpec> getArgToFuncMapping() throws FrontendException {
List<FuncSpec> funcList = new ArrayList<FuncSpec>();
Schema s = new Schema();
s.add(new Schema.FieldSchema(null, DataType.BYTEARRAY));
s.add(new Schema.FieldSchema(null, DataType.BYTEARRAY));
funcList.add(new FuncSpec(this.getClass().getName(), s));
s = new Schema();
s.add(new Schema.FieldSchema(null, DataType.CHARARRAY));
s.add(new Schema.FieldSchema(null, DataType.CHARARRAY));
funcList.add(new FuncSpec(StringConcat.class.getName(), s));
return funcList;
}
}