org.apache.hadoop.hive.ql.udf.UDFMd5Hash.java Source code

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Here is the source code for org.apache.hadoop.hive.ql.udf.UDFMd5Hash.java

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/**
* Tencent is pleased to support the open source community by making TDW available.
* Copyright (C) 2014 THL A29 Limited, a Tencent company. All rights reserved.
* 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 org.apache.hadoop.hive.ql.udf;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.hive.conf.HiveConf;
import org.apache.hadoop.hive.ql.exec.UDF;
import org.apache.hadoop.io.DoubleWritable;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;

public class UDFMd5Hash extends UDF {

    private static Log l4j = LogFactory.getLog(HiveConf.class);
    private static final String[] hexDigits = { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b", "c",
            "d", "e", "f" };

    public String evaluate(LongWritable in, Text seed) {
        if (in == null || seed == null) {
            return null;
        }
        String toEncrypt = null;
        if (seed.getLength() == 0) {
            toEncrypt = in.toString() + seed;
            return getMd5(toEncrypt);
        } else {
            byte[] inBytes = in.toString().getBytes();
            byte[] toEncryptB = new byte[inBytes.length + seed.getLength()];
            System.arraycopy(inBytes, 0, toEncryptB, 0, inBytes.length);
            System.arraycopy(seed.getBytes(), 0, toEncryptB, inBytes.length, seed.getLength());

            return getMd5(toEncryptB);
        }
    }

    public String evaluate(DoubleWritable in, Text seed) {
        if (in == null || seed == null) {
            return null;
        }
        String toEncrypt = null;
        if (seed.getLength() == 0) {
            toEncrypt = in.toString() + seed;
            return getMd5(toEncrypt);
        } else {
            byte[] inBytes = in.toString().getBytes();
            byte[] toEncryptB = new byte[inBytes.length + seed.getLength()];
            System.arraycopy(inBytes, 0, toEncryptB, 0, inBytes.length);
            System.arraycopy(seed.getBytes(), 0, toEncryptB, inBytes.length, seed.getLength());

            return getMd5(toEncryptB);
        }
    }

    public String evaluate(IntWritable in, Text seed) {
        if (in == null || seed == null) {
            return null;
        }
        String toEncrypt = null;
        if (seed.getLength() == 0) {
            toEncrypt = in.toString() + seed;
            return getMd5(toEncrypt);
        } else {
            byte[] inBytes = in.toString().getBytes();
            byte[] toEncryptB = new byte[inBytes.length + seed.getLength()];
            System.arraycopy(inBytes, 0, toEncryptB, 0, inBytes.length);
            System.arraycopy(seed.getBytes(), 0, toEncryptB, inBytes.length, seed.getLength());

            return getMd5(toEncryptB);
        }
    }

    public String evaluate(Text in, Text seed) {
        if (in == null || seed == null) {
            return null;
        }

        byte[] toEncrypt = new byte[in.getLength() + seed.getLength()];
        System.arraycopy(in.getBytes(), 0, toEncrypt, 0, in.getLength());
        System.arraycopy(seed.getBytes(), 0, toEncrypt, in.getLength(), seed.getLength());

        return getMd5(toEncrypt);
    }

    private static String byteArrayToHexString(byte[] b) {
        StringBuffer resultSb = new StringBuffer();
        for (int i = 0; i < b.length; i++) {
            resultSb.append(byteToHexString(b[i]));
        }
        return resultSb.toString();
    }

    private static String byteToHexString(byte b) {
        int n = b;
        if (n < 0)
            n = 256 + n;
        int d1 = n / 16;
        int d2 = n % 16;
        return hexDigits[d1] + hexDigits[d2];
    }

    private static String getMd5(String toEncrypt) {
        try {
            byte[] results = MessageDigest.getInstance("MD5").digest(toEncrypt.getBytes());
            String resultString = byteArrayToHexString(results);
            return resultString;
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
            return null;
        }
    }

    private static String getMd5(byte[] toEncrypt) {
        try {
            byte[] results = MessageDigest.getInstance("MD5").digest(toEncrypt);
            String resultString = byteArrayToHexString(results);
            return resultString;
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
            return null;
        }
    }

    public static void main(String[] args) throws NoSuchAlgorithmException {

        UDFMd5Hash md5test = new UDFMd5Hash();
        LongWritable in1 = new LongWritable(12345678);
        String seed = "helloworld";
        DoubleWritable in2 = new DoubleWritable(12345678.0);
        String in3 = "12345678";
        //System.out.println(md5test.evaluate(in1, seed));
        //System.out.println(md5test.evaluate(in2, seed));
        //System.out.println(md5test.evaluate(in3, seed));
    }
}