Java MD5 Sum md5sum(InputStream in)

Description

mdsum

License

Open Source License

Declaration

public static String md5sum(InputStream in) throws IOException, NoSuchAlgorithmException 

Method Source Code

//package com.java2s;
/*/*  w ww  .  j a  v a  2 s .  c  o  m*/
 * Copyright (C) 2012 Joseph Areeda <joseph.areeda at ligo.org>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

import java.io.ByteArrayOutputStream;

import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;

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

public class Main {
    public static String md5sum(InputStream in) throws IOException, NoSuchAlgorithmException {
        in.reset();
        MessageDigest md = MessageDigest.getInstance("MD5");
        byte[] dataBytes = new byte[1024];

        int nread;
        while ((nread = in.read(dataBytes)) != -1) {
            md.update(dataBytes, 0, nread);
        }
        return getMd5String(md);
    }

    public static String md5sum(byte[] data) throws NoSuchAlgorithmException {
        MessageDigest md = MessageDigest.getInstance("MD5");
        md.update(data, 0, data.length);
        return getMd5String(md);
    }

    public static String md5sum(float[] data) {
        String ret = "error";
        try {
            byte[] b = float2ByteArray(data);
            ret = md5sum(b);
        } catch (Exception ex) {
            String ermsg = "Calculating md5sum of data: " + ex.getClass().getSimpleName() + " - "
                    + ex.getLocalizedMessage();
        }
        return ret;
    }

    public static String getMd5String(MessageDigest md) {
        byte[] mdbytes = md.digest();

        //convert the byte to hex format method 1
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < mdbytes.length; i++) {
            sb.append(Integer.toString((mdbytes[i] & 0xff) + 0x100, 16).substring(1));
        }
        return sb.toString();
    }

    /**
     * 
     * @param data
     * @return 
     */
    public static byte[] float2ByteArray(float[] data) throws IOException {
        byte[] ret;
        int len = data.length;
        ByteArrayOutputStream bos = new ByteArrayOutputStream(len * Float.SIZE / 8);
        DataOutputStream dos = new DataOutputStream(bos);
        for (int in = 0; in < len; in++) {
            dos.writeFloat(data[in]);
        }
        ret = bos.toByteArray();

        return ret;
    }
}

Related

1. md5sum(File f, char[] cbuf, MessageDigest digest, byte[] bbuf)
2. md5sum(File file)
3. md5sum(File file)
4. md5sum(File library)
5. md5sum(InputStream file)
6. md5sum(String data)
7. md5sum(String input)
8. md5sum(String inString)
9. md5sum(String message)