HashUtils.java 工具类

 

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class HashUtils {

    private static String[] hexCode = { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };
    private static final int TWO_HUNDERDS_AND_FIFTY_SIX = 256;
    private static final int SIXTEEN = 16;

    private static String byteToHexString(byte b) {
        int n = b;
        if (n < 0) {
            n = TWO_HUNDERDS_AND_FIFTY_SIX + n;
        }
        int d1 = n / SIXTEEN;
        int d2 = n % SIXTEEN;
        return hexCode[d1] + hexCode[d2];
    }

    private static String byteArrayToHexString(byte[] b) {
        StringBuilder result = new StringBuilder();
        for (int i = 0; i < b.length; i++) {
            result.append(byteToHexString(b[i]));
        }
        return result.toString();
    }
    
    public static String hashSHA256(byte[] input){
        MessageDigest md = null;
        try {
            md = MessageDigest.getInstance("SHA-256");
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        }
        byte[] digest = md.digest(input);
        return byteArrayToHexString(digest);
    }

    
}