java当中Md5加密总结

package test;

import java.security.MessageDigest;

public class Md5 {
	 /** 
     * MD5加密 
     * @param message 要进行MD5加密的字符串 
     * @return 加密结果为32位小写字符串 
     */  
    public static String getMD532Big(String message) {  
        MessageDigest messageDigest = null;  
        StringBuffer md5StrBuff = new StringBuffer();  
        try {  
            messageDigest = MessageDigest.getInstance("MD5");  
            messageDigest.reset();  
            messageDigest.update(message.getBytes("UTF-8"));  
              
            byte[] byteArray = messageDigest.digest();  
            for (int i = 0; i < byteArray.length; i++)   
            {  
                if (Integer.toHexString(0xFF & byteArray[i]).length() == 1)  
                    md5StrBuff.append("0").append(Integer.toHexString(0xFF & byteArray[i]));  
                else  
                    md5StrBuff.append(Integer.toHexString(0xFF & byteArray[i]));  
            }  
        } catch (Exception e) {  
            throw new RuntimeException();  
        }  
        return md5StrBuff.toString().toUpperCase();//字母大写  
    }  
    /** 
     * MD5加密 
     * @param message 要进行MD5加密的字符串 
     * @return 加密结果为32位大写字符串 
     */  
    public static String getMD532Small(String message) {  
        MessageDigest messageDigest = null;  
        StringBuffer md5StrBuff = new StringBuffer();  
        try {  
            messageDigest = MessageDigest.getInstance("MD5");  
            messageDigest.reset();  
            messageDigest.update(message.getBytes("UTF-8"));  
              
            byte[] byteArray = messageDigest.digest();  
            for (int i = 0; i < byteArray.length; i++)   
            {  
                if (Integer.toHexString(0xFF & byteArray[i]).length() == 1)  
                    md5StrBuff.append("0").append(Integer.toHexString(0xFF & byteArray[i]));  
                else  
                    md5StrBuff.append(Integer.toHexString(0xFF & byteArray[i]));  
            }  
        } catch (Exception e) {  
            throw new RuntimeException();  
        }  
        return md5StrBuff.toString();
    }  
    /** 
     * MD5加密 
     * @param message 要进行MD5加密的字符串 
     * @return 加密结果为16位大写字符串 
     */  
    static String MD516Big(String message) {
        String result = "";
        try {
            MessageDigest md = MessageDigest.getInstance("MD5");
            md.update(message.getBytes());
            byte b[] = md.digest();
            int i;
            StringBuffer buf = new StringBuffer("");
            for (int offset = 0; offset < b.length; offset++) {
                i = b[offset];
                if (i < 0)
                    i += 256;
                if (i < 16)
                    buf.append("0");
                buf.append(Integer.toHexString(i));
            }
            result = buf.toString().substring(8, 24).toUpperCase();
        } catch (Exception e) {
        	throw new RuntimeException();  
        }
        return result;
    }
    /** 
     * MD5加密 
     * @param message 要进行MD5加密的字符串 
     * @return 加密结果为16位小写字符串 
     */  
    static String MD516Small(String message) {
        String result = "";
        try {
            MessageDigest md = MessageDigest.getInstance("MD5");
            md.update(message.getBytes());
            byte b[] = md.digest();
            int i;
            StringBuffer buf = new StringBuffer("");
            for (int offset = 0; offset < b.length; offset++) {
                i = b[offset];
                if (i < 0)
                    i += 256;
                if (i < 16)
                    buf.append("0");
                buf.append(Integer.toHexString(i));
            }
            result = buf.toString().substring(8, 24);
        } catch (Exception e) {
            System.out.println(e);
        }
        return result;
    }

}