java md5编译错误

Question

我只是尝试在java中使用MD5库，但是我遇到了一些错误，

当我尝试编译它时，出现此错误:

digest(byte[],int,int) in java.security.MessageDigest cannot be applied to (byte[])

I try to compile it by wtk (j2me)What is the problem ?. thanks

here is the code

import java.io.FileInputStream;
import java.io.UnsupportedEncodingException;
import java.math.BigInteger;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class MD5 {
    public static String getMD5(String input) {
        try {
            MessageDigest md = MessageDigest.getInstance("MD5");
            byte[] messageDigest = md.digest(input.getBytes());
            BigInteger number = new BigInteger(1, messageDigest);
            String hashtext = number.toString(16);
            // Now we need to zero pad it if you actually want the full 32 chars.
            while (hashtext.length() < 32) {
                hashtext = "0" + hashtext;
            }
            return hashtext;
        }
        catch (NoSuchAlgorithmException e) {
            throw new RuntimeException(e);
        }
    }

    public static void main(String[] args) throws NoSuchAlgorithmException {
        System.out.println(getMD5("Javarmi.com"));
    }
}

Answer 1

既然你使用WTK，也许你有this version of MessageDigest ，它没有digest(byte[])。所以，你需要写这样的东西:

int MD_SIZE = 16;
byte[] messageDigest = new byte[MD_SIZE];
byte[] message = ...;
md.update(message, 0, message.length);
md.digest(messageDigest, 0, MD_SIZE);

另请注意，您使用了String.getBytes()，因此您的摘要取决于系统默认编码。您需要使用String.getBytes(String encoding)才能获得可移植的结果。