安全编程之普通MD5加密

MD5加密基础篇应用，就直接上代码

import java.security.MessageDigest;

public class MD5 {


    /***
     * 普通MD5
     * MD5加码 生成32位md5码
     */
    public static String string2MD5(String inStr){
        MessageDigest md5 = null;
        try{
            md5 = MessageDigest.getInstance("MD5");
        }catch (Exception e){
            System.out.println(e.toString());
            e.printStackTrace();
            return "";
        }
        char[] charArray = inStr.toCharArray();
        byte[] byteArray = new byte[charArray.length];

        for (int i = 0; i < charArray.length; i++)
            byteArray[i] = (byte) charArray[i];
        byte[] md5Bytes = md5.digest(byteArray);
        StringBuffer hexValue = new StringBuffer();
        for (int i = 0; i < md5Bytes.length; i++){
            int val = ((int) md5Bytes[i]) & 0xff;
            if (val < 16)
                hexValue.append("0");
            hexValue.append(Integer.toHexString(val));
        }
        return hexValue.toString();

    }

    /**
     * 加密解密算法 执行一次加密，两次解密
     */
    public static String convertMD5(String inStr){

        char[] a = inStr.toCharArray();
        for (int i = 0; i < a.length; i++){
            a[i] = (char) (a[i] ^ 't');
        }
        String s = new String(a);
        return s;

    }

    /**
     *  main函数
     */
    public static void main(String args[]) {
        String s = "liuqiang12345";
        String string2MD5 = string2MD5(s);
        System.out.println("md5Str:"+string2MD5); //加密后的字符串

        String convertMD5 = convertMD5(s);
        System.out.println("转换MD5：" + convertMD5);
        String resolveConvertMD5 = convertMD5(convertMD5);
        System.out.println("解析转换MD5" + resolveConvertMD5);

    }


}