/*
 * 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.piggybank.evaluation.string;

import java.io.IOException;

import org.apache.pig.data.Tuple;

/**
* <dl>
* Implementation for HashFNV which takes 2 parameter
* </dl>
*/
public class HashFNV2 extends HashFNV {
    int mMod=-1;
    @Override
    public Long exec(Tuple input) throws IOException {
        if (input.size()!=2) {
            String msg = "HashFNV : Only 2 parameters are allowed.";
            throw new IOException(msg);
        }
        if (input.get(0)==null || input.get(1)==null)
            return null;
        try {
            mMod = (Integer)input.get(1);
        } catch (ClassCastException e) {
            throw new IOException("HashFNV : 2nd parameter is not Integer",e);
        }
        
        long v = hashFnv32((String)input.get(0));
        if (v < 0)
            v = -v;
        if (mMod > 0)
        {
            v %= mMod;
        }
        return v;
    }
}
