18

参考部分网上代码

对中文加密还有些问题

package com.copote.function.text;

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.ArrayList;
import java.util.List;

/**
 * MD5加密方式
 * 包含md5和md5_3
 * 根据js代码改写，md5改写
 * @author  bin
 * 对中文的支持不好，如果非要中文，加密的是UTF8的
 */
public class FunctionTextMd5 {
    
	private final static char[] dictionary = { '0', '1', '2', '3', '4', '5',
		'6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };

	public static void main(String[] args) {
		System.out.println(new FunctionTextMd5().md5_3("22222222"));
	}
	public String md5(String str) {
		String md5str = "";
		try {
			md5str = code(str, 32);
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return md5str;
	}
	
	public String md5_3(String str) {
		MessageDigest md = null;
		try {
			md = MessageDigest.getInstance(System.getProperty("MD5.algorithm", "MD5"));
		} catch (NoSuchAlgorithmException e1) {
			// TODO Auto-generated catch block
			e1.printStackTrace();
		}
		byte[] temp = null;
		try {
			temp = md.digest(str.getBytes("utf-8"));//第一次加密
		} catch (UnsupportedEncodingException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		temp = md.digest(temp);//第二次加密
		temp = md.digest(temp);//第三次加密
		return bytesToHex(temp);
	}
	
	public String bytesToHex(byte[] bytes) {
		String str = "";
		int t;
		for (int i = 0; i < 16; i++) {
			t = bytes[i];
			if (t < 0)
				t += 256;
			str += dictionary[(t >>> 4)];
			str += dictionary[(t % 16)];
		}
		return str;
	}

	public String code(String str, int bit) throws Exception {
		try {
			MessageDigest md = MessageDigest.getInstance(System.getProperty("MD5.algorithm", "MD5"));
			if (bit == 16)
				return bytesToHex(md.digest(str.getBytes("utf-8"))).substring(8, 24);
			return bytesToHex(md.digest(str.getBytes("utf-8")));

		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
			throw new Exception("Could not found MD5 algorithm.", e);
		}
	}
}