JAVA Message Digest Useful __java

Network computing environment in a lot of time need to file a message digest calculation, to prevent file tampering, verify whether the file has been modified, the JDK itself provides a message digest algorithm, very convenient to use, mainly used in Security digest calculation class

Java.security.MessageDigest, as follows:

Package com.test.b;
Import Java.io.BufferedInputStream;
Import Java.io.FileInputStream;
Import Java.io.InputStream;

Import Java.security.MessageDigest; public class Messagedigesttest {/** * @param args * @throws Exception/public static void main  (string[] args) throws Exception {String file = "Mm.txt";
        The file is commessdigest (file, "SHA-1") for the required summary calculation;
    Commessdigest (file, "MD5"); /** * * @param name filename * @param MD Digest algorithm * @throws Exception/public Stati c void Commessdigest (String name,string md) throws exception{MessageDigest digest = messagedigest.getinstance (MD)
        ;
        
        InputStream in = new Bufferedinputstream (new FileInputStream (name));
        int ch;
        while ((ch = in.read ())!=-1) {//update digest with the specified byte Digest.update ((byte) ch);
        } in.close ();
        Complete hash summary calculation byte[] hash = digest.digest ();
 Printresult (hash);   /** * Print Summary results * @param scoure */public static void Printresult (byte[) scoure) {St
        Ringbuilder builder = new StringBuilder ();
        for (byte c:scoure) {builder.append (int) c);
    } System.out.println (Builder.tostring ());
 }
}

The results are as follows:

682289988-127418543-1277977120-372-125-36-5364105
-96-19-641210641-72-77-6282-8-67-611221005