AESUtil

package com.tebon.ams.util;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import java.security.Key;
import java.security.NoSuchAlgorithmException;

/**
* @description: ${description}
* @author: dfz
* @create: 2019-05-16
**/
public class AES {
private static final String KEY_ALGORITHM = "AES";
private static final String DEFAULT_CIPHER_ALGORITHM = "AES/ECB/PKCS5Padding";//默认的加密算法

public static byte[] initSecretKey() {

//返回生成指定算法密钥生成器的 KeyGenerator 对象
KeyGenerator kg = null;
try {
kg = KeyGenerator.getInstance(KEY_ALGORITHM);
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
return new byte[0];
}
//初始化此密钥生成器,使其具有确定的密钥大小
//AES 要求密钥长度为 128
kg.init(128);
//生成一个密钥
SecretKey secretKey = kg.generateKey();
return secretKey.getEncoded();
}

private static Key toKey(byte[] key){
//生成密钥
return new SecretKeySpec(key, KEY_ALGORITHM);
}

public static byte[] encrypt(byte[] data,Key key) throws Exception{
return encrypt(data, key,DEFAULT_CIPHER_ALGORITHM);
}

public static byte[] encrypt(byte[] data,byte[] key) throws Exception{
return encrypt(data, key,DEFAULT_CIPHER_ALGORITHM);
}

public static byte[] encrypt(byte[] data,byte[] key,String cipherAlgorithm) throws Exception{
//还原密钥
Key k = toKey(key);
return encrypt(data, k, cipherAlgorithm);
}

public static byte[] encrypt(byte[] data,Key key,String cipherAlgorithm) throws Exception{
//实例化
Cipher cipher = Cipher.getInstance(cipherAlgorithm);
//使用密钥初始化,设置为加密模式
cipher.init(Cipher.ENCRYPT_MODE, key);
//执行操作
return cipher.doFinal(data);
}

public static byte[] decrypt(byte[] data,byte[] key) throws Exception{
return decrypt(data, key,DEFAULT_CIPHER_ALGORITHM);
}

public static byte[] decrypt(byte[] data,Key key) throws Exception{
return decrypt(data, key,DEFAULT_CIPHER_ALGORITHM);
}

public static byte[] decrypt(byte[] data,byte[] key,String cipherAlgorithm) throws Exception{
//还原密钥
Key k = toKey(key);
return decrypt(data, k, cipherAlgorithm);
}

public static byte[] decrypt(byte[] data,Key key,String cipherAlgorithm) throws Exception{
//实例化
Cipher cipher = Cipher.getInstance(cipherAlgorithm);
//使用密钥初始化,设置为解密模式
cipher.init(Cipher.DECRYPT_MODE, key);
//执行操作
return cipher.doFinal(data);
}

private static String showByteArray(byte[] data){
if(null == data){
return null;
}
StringBuilder sb = new StringBuilder("{");
for(byte b:data){
sb.append(b).append(",");
}
sb.deleteCharAt(sb.length()-1);
sb.append("}");
return sb.toString();
}

public static void main(String[] args) throws Exception {
byte[] key = initSecretKey();
System.out.println("key:"+showByteArray(key));
Key k = toKey(key); //生成秘钥
String data ="1234567890";
System.out.println("加密前数据: string:"+data);
System.out.println("加密前数据: byte[]:"+showByteArray(data.getBytes()));
System.out.println();
byte[] encryptData = encrypt(data.getBytes(), k);//数据加密
System.out.println("加密后数据: byte[]:"+showByteArray(encryptData));
// System.out.println("加密后数据: hexStr:"+Hex.encodeHexStr(encryptData));
System.out.println();
byte[] decryptData = decrypt(encryptData, k);//数据解密
System.out.println("解密后数据: byte[]:"+showByteArray(decryptData));
System.out.println("解密后数据: string:"+new String(decryptData));
}
}
posted @ 2019-05-16 11:02  ding9587  阅读(271)  评论(0编辑  收藏  举报