MD5 - com.Ostermiller.util Java Utilities

System.out.println(
    MD5.getHashString(
        "Hello World"
    )
);

This class takes as input a message of arbitrary length and produces as output a 128-bit "fingerprint" or "message digest" of the input. It is conjectured that it is computationally infeasible to produce two messages having the same message digest, or to produce any message having a given pre-specified target message digest. The MD5 algorithm is intended for digital signature applications, where a large file must be "compressed" in a secure manner before being encrypted with a private (secret) key under a public-key cryptosystem such as RSA.

This class is based on work by Santeri Paavolainen. and RFC1321. This implementation is several times faster and much more memory efficient than Santeri's implementation.

// Print the MD5 hash for a line
// read from standard input
MD5InputStream in = new MD5InputStream(System.in);
int b;
while ((b = in.read()) != -1 && b != '\r' && b != '\n');
System.out.println(in.getHashString());

Input Stream

A filtered input stream that computes an MD5 sum for anything read.

// Write out hello world
// and print its MD5 hash 
MD5OutputStream out = new MD5OutputStream(System.out);
out.write("Hello World\n".getBytes());
System.out.println(out.getHashString());

Output Stream

A filtered output stream that computes an MD5 sum for anything written.