HashFunctionTest.groovy

import java.security.DigestInputStream
import java.security.MessageDigest
import java.util.zip.CRC32
import java.util.zip.CheckedInputStream

def calculateHash(String fileName) {
    MessageDigest md5 = MessageDigest.getInstance('MD5')
    MessageDigest sha1 = MessageDigest.getInstance('SHA-1')
    MessageDigest sha256 = MessageDigest.getInstance('SHA-256')
    MessageDigest sha512 = MessageDigest.getInstance('SHA-512')

    FileInputStream fis = new FileInputStream(fileName)
    BufferedInputStream bis = new BufferedInputStream(fis)

    DigestInputStream md5Dis = new DigestInputStream(bis, md5)
    DigestInputStream sha1Dis = new DigestInputStream(md5Dis, sha1)
    DigestInputStream sha256Dis = new DigestInputStream(sha1Dis, sha256)
    DigestInputStream sha512Dis = new DigestInputStream(sha256Dis, sha512)

    CheckedInputStream checkIn = new CheckedInputStream(sha512Dis, new CRC32())

    while (checkIn.read() != -1);

    fis.close()

    println "MD5    " + byteArray2Hex(md5.digest())
    println "SHA1   " + byteArray2Hex(sha1.digest())
    println "SHA256 " + byteArray2Hex(sha256.digest())
    println "SHA512 " + byteArray2Hex(sha512.digest())
    println "CRC32  " + checkIn.checksum.value
}

String byteArray2Hex(byte[] hash) {
    Formatter formatter = new Formatter()
    for (byte b : hash) {
        formatter.format('%02x', b)
    }
    return formatter
}

calculateHash('C:\\Windows\\win.ini')