Example usage for java.math BigInteger BigInteger

Introduction

In this page you can find the example usage for java.math BigInteger BigInteger.

Prototype

private BigInteger(byte[] magnitude, int signum)

Source Link

Document

This private constructor is for internal use and assumes that its arguments are correct.

Usage

From source file:Main.java

/**
 * generates MD5 of input string/*w  w w . ja v a 2 s.  c  o  m*/
 *
 * @param input string to be hashed
 * @return MD5 hash of string
 */
public static String getMD5(String input) {

    MessageDigest m = null;
    try {
        m = MessageDigest.getInstance("MD5");
    } catch (NoSuchAlgorithmException e) {
        e.printStackTrace();
    }
    m.reset();
    m.update(input.getBytes());
    byte[] digest = m.digest();
    BigInteger bigInt = new BigInteger(1, digest);
    String hashtext = bigInt.toString(16);
    //zero pad to get the full 32 chars.
    while (hashtext.length() < 32) {
        hashtext = "0" + hashtext;
    }
    return hashtext;
}

From source file:D_common.E_ncript.java

public static String getMd5(String s) {
    try {//w  ww. j a  v a 2s.co  m
        MessageDigest m = MessageDigest.getInstance("MD5");
        m.update(s.getBytes(), 0, s.length());
        return new BigInteger(1, m.digest()).toString(16);
    } catch (Exception e) {
        e.printStackTrace();
        return "";
    }
}

From source file:Main.java

public static String getFileMd5String(File file) {
    if (!file.isFile())
        throw new IllegalArgumentException("only file can calculate MD5 value!");

    MessageDigest digest;/* w  ww  .jav  a 2  s  .c  o  m*/
    FileInputStream in = null;
    byte buffer[] = new byte[8192];
    int len;
    try {
        digest = MessageDigest.getInstance("MD5");
        in = new FileInputStream(file);
        while ((len = in.read(buffer)) != -1) {
            digest.update(buffer, 0, len);
        }
        BigInteger bigInt = new BigInteger(1, digest.digest());
        return bigInt.toString(16);
    } catch (Exception e) {
        e.printStackTrace();
        return null;
    } finally {
        try {
            if (in != null)
                in.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

From source file:Main.java

private static long readThreadAddres(String line) {
    int start = line.indexOf("0x"); //$NON-NLS-1$
    if (start < 0)
        return -1;
    return (new BigInteger(line.substring(start + 2), 16)).longValue();
}

From source file:Main.java

public static String bin2hex(byte[] data) {
    return String.format("%0" + (data.length * 2) + "X", new BigInteger(1, data));
}

From source file:Main.java

public static String getFileMD5(File file) {
    if (!file.isFile()) {
        return null;
    }// w  ww. j a  v  a 2s. c  om
    MessageDigest digest = null;
    FileInputStream in = null;
    byte buffer[] = new byte[1024];
    int len;
    try {
        digest = MessageDigest.getInstance("MD5");
        in = new FileInputStream(file);
        while ((len = in.read(buffer, 0, 1024)) != -1) {
            digest.update(buffer, 0, len);
        }
        in.close();
    } catch (Exception e) {
        e.printStackTrace();
        return null;
    }
    BigInteger bigInt = new BigInteger(1, digest.digest());
    return bigInt.toString(16);
}

From source file:Main.java

public static String checkSum(String path) {
    String checksum = null;/*from w w w.j a  va2  s . co  m*/
    try {
        FileInputStream fis = new FileInputStream(path);
        MessageDigest md = MessageDigest.getInstance("MD5");

        //Using MessageDigest update() method to provide input
        byte[] buffer = new byte[8192];
        int numOfBytesRead;
        while ((numOfBytesRead = fis.read(buffer)) > 0) {
            md.update(buffer, 0, numOfBytesRead);
        }
        byte[] hash = md.digest();
        checksum = new BigInteger(1, hash).toString(16); //don't use this, truncates leading zero
    } catch (IOException | NoSuchAlgorithmException ignored) {
    }
    assert checksum != null;
    return checksum.trim();
}

From source file:Main.java

/**
 * Generate a hash chain of a random number
 * @param r1/*from   ww  w. j  a  va2s . com*/
 * @param numHash
 * @return
 * @throws NoSuchAlgorithmException
 * @throws UnsupportedEncodingException
 */
public static LinkedList<BigInteger> getHashChain(BigInteger r1, int numHash)
        throws NoSuchAlgorithmException, UnsupportedEncodingException {

    LinkedList<BigInteger> hashChain = new LinkedList<BigInteger>();
    hashChain.add(r1);

    for (int i = 1; i < numHash; i++) {
        byte[] lastR = hashChain.getLast().toByteArray();
        hashChain.add(new BigInteger(1, SHA1(lastR)));
    }

    return hashChain;
}

From source file:Main.java

public static String getMD5EncryptedString(byte[] _encTarget) {
    String encTarget = "";
    try {//from  w  ww.j  a  v  a  2s  . c o m
        encTarget = new String(_encTarget, "UTF-8");
    } catch (UnsupportedEncodingException e1) {
        System.out.println("error converting byte[] to string");
    }
    MessageDigest mdEnc = null;
    try {
        mdEnc = MessageDigest.getInstance("MD5");
    } catch (NoSuchAlgorithmException e) {
        System.out.println("Exception while encrypting to md5");
    } // Encryption algorithm
    mdEnc.update(encTarget.getBytes(), 0, encTarget.length());
    String md5 = new BigInteger(1, mdEnc.digest()).toString(16);
    while (md5.length() < 32) {
        md5 = "0" + md5;
    }
    return md5;
}

From source file:Main.java

/**
 * Returns the lowercase string representation of the file's MD5 sum.
 *///from  w  w w  .ja  va 2s . c o m
public static String getMD5Sum(String file) throws IOException {
    try {
        MessageDigest digest = MessageDigest.getInstance("MD5");
        InputStream is = new FileInputStream(file);
        byte[] buffer = new byte[8192];
        int read = 0;
        while ((read = is.read(buffer)) > 0) {
            digest.update(buffer, 0, read);
        }
        is.close();
        byte[] md5sum = digest.digest();
        BigInteger bigInt = new BigInteger(1, md5sum);
        return bigInt.toString(16);
    } catch (NoSuchAlgorithmException e) {
        return "";
    }
}