AES算法Java实现

package com.tristan.aes;

import java.io.UnsupportedEncodingException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;

import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.KeyGenerator;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;

/**
* @author 【轰隆隆】
*
*/
public class AES {

/**
* AES加密算法
*/
public AES() {
}

/**
* 加密
*
* @param content
*            需要加密的内容
* @param keyWord
*            加密密钥
* @return byte[] 加密后的字节数组
*/
public static byte[] encrypt(String content, String keyWord) {
try {
KeyGenerator kgen = KeyGenerator.getInstance("AES");
SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG");
secureRandom.setSeed(keyWord.getBytes());
kgen.init(128, secureRandom);
SecretKey secretKey = kgen.generateKey();
byte[] enCodeFormat = secretKey.getEncoded();
SecretKeySpec key = new SecretKeySpec(enCodeFormat, "AES");
Cipher cipher = Cipher.getInstance("AES");// 创建密码器
byte[] byteContent = content.getBytes("utf-8");
cipher.init(Cipher.ENCRYPT_MODE, key);// 初始化
byte[] result = cipher.doFinal(byteContent);
return result; // 加密
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (NoSuchPaddingException e) {
e.printStackTrace();
} catch (InvalidKeyException e) {
e.printStackTrace();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (IllegalBlockSizeException e) {
e.printStackTrace();
} catch (BadPaddingException e) {
e.printStackTrace();
}
return null;
}

/**
* @param content
*            需要加密的内容
* @param password
*            加密密钥
* @return String 加密后的字符串
*/
public static String encrypttoStr(String content, String password) {
return parseByte2HexStr(encrypt(content, password));
}

/**
* 解密
*
* @param content
*            待解密内容
* @param keyWord
*            解密密钥
* @return byte[]
*/
public static byte[] decrypt(byte[] content, String keyWord) {
try {
KeyGenerator kgen = KeyGenerator.getInstance("AES");
SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG");
secureRandom.setSeed(keyWord.getBytes());
kgen.init(128, secureRandom);
SecretKey secretKey = kgen.generateKey();
byte[] enCodeFormat = secretKey.getEncoded();
SecretKeySpec key = new SecretKeySpec(enCodeFormat, "AES");
Cipher cipher = Cipher.getInstance("AES");// 创建密码器
cipher.init(Cipher.DECRYPT_MODE, key);// 初始化
byte[] result = cipher.doFinal(content);
return result; // 加密
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (NoSuchPaddingException e) {
e.printStackTrace();
} catch (InvalidKeyException e) {
e.printStackTrace();
} catch (IllegalBlockSizeException e) {
e.printStackTrace();
} catch (BadPaddingException e) {
e.printStackTrace();
}
return null;
}

/**
* @param content
*            待解密内容(字符串)
* @param keyWord
*            解密密钥
* @return byte[]
*/
public static byte[] decrypt(String content, String keyWord) {
return decrypt(parseHexStr2Byte(content), keyWord);
}

/**
* 将二进制转换成16进制
*
* @param buf
* @return String
*/
public static String parseByte2HexStr(byte buf[]) {
StringBuffer sb = new StringBuffer();
for (int i = 0; i < buf.length; i++) {
String hex = Integer.toHexString(buf[i] & 0xFF);
if (hex.length() == 1) {
hex = '0' + hex;
}
sb.append(hex.toUpperCase());
}
return sb.toString();
}

/**
* 将16进制转换为二进制
*
* @param hexStr
* @return byte[]
*/
public static byte[] parseHexStr2Byte(String hexStr) {
if (hexStr.length() < 1)
return null;
byte[] result = new byte[hexStr.length() / 2];
for (int i = 0; i < hexStr.length() / 2; i++) {
int high = Integer.parseInt(hexStr.substring(i * 2, i * 2 + 1), 16);
int low = Integer.parseInt(hexStr.substring(i * 2 + 1, i * 2 + 2),
16);
result[i] = (byte) (high * 16 + low);
}
return result;
}

public static void main(String[] args) {
String content = "HongLongLong";
String Key = "http://www.honglonglong.com";

// 加密
System.out.println("加密前：" + content);
String encryptResult = encrypttoStr(content, Key);
System.out.println("加密后：" + encryptResult);
// 解密
byte[] decryptResult = decrypt(encryptResult, Key);
System.out.println("解密后：" + new String(decryptResult));
}
}