TestAES256--這纔是加密的最佳方式，目前。畢竟是advance

//代碼與DES的基本一致，除了使用規範，初始化長度替換下
//注意事項：需要替換jre/lib/security下的*_policy.jar，附上全版本替換JCE附件。
//鏈接: http://pan.baidu.com/s/1dDLE1Gl 提取密碼: 6sqw
import java.security.Key;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;

import org.apache.commons.codec.binary.Base64;

public class TestAES256 {
	
public static String KEY_ALGORITHM ="AES";
	
	public static String CIPHER_ALOGITHM ="AES/ECB/PKCS5Padding";
	
	public static void main(String[] args) throws Exception{
		String s = "AES";
		System.out.println("原文： " + s);
		byte[] key = initKey();
		System.out.println("密鑰： " + Base64.encodeBase64String(key));
		byte[] afterEncrypt = encrypt(s.getBytes(), key);
		System.out.println("加密後:" + Base64.encodeBase64String(afterEncrypt));
		
		byte[] afterDecrypt = decrypt(afterEncrypt, key);
		System.out.println("解密後：" + new String(afterDecrypt));
		
	}
	
	public static byte[] initKey() throws Exception {
		KeyGenerator kg = KeyGenerator.getInstance(KEY_ALGORITHM);
		kg.init(256);
		SecretKey sk = kg.generateKey();
		return sk.getEncoded();
	}
	
	/**
	 * 轉換密鑰
	 * @param key
	 * @return
	 * @throws Exception
	 */
	public static Key toKey(byte[] key) throws Exception {
		//獲取密鑰模具，規範
		SecretKey ss = new SecretKeySpec(key, KEY_ALGORITHM);

		return ss;
	}
	
	public static byte[] encrypt(byte[] date, byte[] key) throws Exception {
		//還原密鑰
		Key k = toKey(key);
		Cipher cipher = Cipher.getInstance(CIPHER_ALOGITHM);
		cipher.init(Cipher.ENCRYPT_MODE, k);
		return cipher.doFinal(date);
	}
	
	/**
	 * 解密
	 * @param date
	 * @param key
	 * @return
	 * @throws Exception
	 */
	public static byte[] decrypt(byte[] date, byte[] key) throws Exception {
		//還原密鑰
		Key k = toKey(key);
		Cipher cipher = Cipher.getInstance(CIPHER_ALOGITHM);
		cipher.init(Cipher.DECRYPT_MODE, k);
		return cipher.doFinal(date);
	}

}