java 加密解密的代码

 

 

package endual;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.security.Key;
import java.security.NoSuchAlgorithmException;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
public class SecretKeyTest {

	public static void main(String[] args) throws Exception, NoSuchPaddingException {

		    String arg0 = "AES"; //加密算法
		
			//加密,密码cipher的意思.加密和解密都是这个
			Cipher cipher = Cipher.getInstance(arg0) ;//工厂创建出一个对象
            //Key arg1;
			//SecretKey key = SecretKeyFactory.getInstance(arg0).generateSecret(arg0) ;
			SecretKey key = KeyGenerator.getInstance(arg0).generateKey() ;
			
			//保持Key
			FileOutputStream fos = new FileOutputStream("wc_secret.key") ;
			ObjectOutputStream oosSecretKey = new ObjectOutputStream(fos) ; 
			oosSecretKey.writeObject(key) ;
			oosSecretKey.close() ;
			fos.close() ;
			//加密的初始化
			cipher.init(Cipher.ENCRYPT_MODE, key) ;
			cipher.update("aaab".getBytes()) ;
			byte[] bytes = cipher.doFinal(); //加密下
			System.out.println(bytes);
			
			//解密
			cipher.init(Cipher.DECRYPT_MODE, key) ;
			byte[] bytes2 = cipher.doFinal(bytes) ;
			System.out.println(new String(bytes2));
			
		
	}
	
	private static void secretSDepect() throws Exception, NoSuchPaddingException {
		String arg0 = "AES"; //加密算法
		
		FileInputStream fis = new FileInputStream("wc_secret.key") ;
		ObjectInputStream objIs = new ObjectInputStream(fis) ;
		Key key = (Key)objIs.readObject() ;
		objIs.close() ;