package com.alibaba.datax.plugin.reader.selfxmlfilereader.util;

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;

/**
* 加密/解密工具
* @author lkm
* @date 2018年9月17日 上午10:52:36
*/
public class EncryptUtil {
public static String PASSWORK = “12345678”;
/**
* 加密
* @param content 需要加密的內容
* @param password 加密密碼
*/
public static byte[] encrypt(String content, String password){
try {
KeyGenerator kgen = KeyGenerator.getInstance(“AES”);
SecureRandom random = SecureRandom.getInstance(“SHA1PRNG”);
random.setSeed(password.getBytes());
kgen.init(128, random);
SecretKey secretKey = kgen.generateKey();
byte[] enCodeFormat = secretKey.getEncoded();
SecretKeySpec key = new SecretKeySpec(enCodeFormat, “AES”);
Cipher cipher = Cipher.getInstance(“AES”);// 建立密碼器
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 (UnsupportedEncodingException e) {
e.printStackTrace();
}catch (InvalidKeyException e) {
e.printStackTrace();
}catch (IllegalBlockSizeException e) {
e.printStackTrace();
}catch (BadPaddingException e) {
e.printStackTrace();
}
return null;
}

/**
 * 解密
 * @param content    待解密內容
 * @param password    解密金鑰
 */
public static byte[] decrypt(byte[] content, String password){
    try {
        KeyGenerator kgen = KeyGenerator.getInstance("AES");
        SecureRandom random = SecureRandom.getInstance("SHA1PRNG");
        random.setSeed(password.getBytes());
        kgen.init(128, random);
        SecretKey secretKey = kgen.generateKey();
        byte[] enCodeFormat = secretKey.getEncoded();
        SecretKeySpec key = new SecretKeySpec(enCodeFormat, "AES");
        Cipher cipher = Cipher.getInstance("AES");// 建立密碼器
        cipher.init(Cipher.DECRYPT_MODE, key);// 初始化
        byte[] result = cipher.doFinal(content);
        return result; // 解密
    } 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;
}

/**
 * 將二進位制轉換成16進位制
 * @method parseByte2HexStr
 * @param buf
 */
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();
}

/**
 * 將16進位制轉換為二進位制
 * @method parseHexStr2Byte
 * @param hexStr
 */
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;
}
/**
 * @method main
 * @param args
 * @throws 
 * @since v1.0
 */
public static void main(String[] args) {
    String content = "加密的內容";
    byte[] encryptResult = encrypt(content, PASSWORK);//加密
    String encryptResultStr = parseByte2HexStr(encryptResult);
    System.out.println("加密後：" + encryptResultStr);

    byte[] decryptFrom = parseHexStr2Byte(encryptResultStr);
    byte[] decryptResult = decrypt(decryptFrom,PASSWORK);//解碼
    System.out.println("解密後：" + new String(decryptResult));

}
 

}