mdio.java

java实现MD5加密,用户输入要加密的字符串.程序处理后输出MD5值

import java.security.*;
import java.util.*;
import java.io.*; 

public class mdio
{
	private String temp;
  private MessageDigest md5;
  private static String postString = null;
  BufferedReader reader;
  
	public mdio()
	{	  
  	try 
 	 { 
    	reader = new BufferedReader(new InputStreamReader(System.in));
    	temp = reader.readLine();
 	 }
 	 catch(IOException ex)
 	 {  	
   	 ex.printStackTrace(); 
 	 }
 	 
	}	
	
	public String compute()
    {
   		char[] charArray = temp.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();
     }
	
	public void wrdatps ()
	{
		try
		{
		String fileName = "G:\\java\\md.dat";
		FileWriter awriter = new FileWriter(fileName);
		awriter.write(postString);
		awriter.close();
	  }
	  catch(IOException e)
	  {
	  	e.printStackTrace();
	  }
	}
	
  public static void main(String args[])
  {
  	System.out.print("请输入md:");
  	mdio md = new mdio(); 
  	
  	try
    {
       md.md5 = MessageDigest.getInstance("MD5");
    }
    catch (Exception e)
    {
       System.out.println(e.toString());
       e.printStackTrace();
    }
  	
  	postString = md.compute();	
  	System.out.println(postString);
  	md.wrdatps();
  }
}