JAVA AES加密/解密

谨以此祭奠我的AES坎坷历程（当作一份笔记）

package com.bubble.encrypt.pass;

import java.io.UnsupportedEncodingException;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

/**
 * Created by Bubble on 2017/6/15.
 * AES-CBC-A28加密解密算法
 */
public class AesUtils {
    /**
     * 算法/模式/填充
     **/
    private static final String CipherMode = "AES/CBC/PKCS5Padding";
    private static String sKey = "";//必须16位
    private static String ivParameter = "ubateubatequanli";//必须16位

    /**
     * 加密(结果为16进制字符串)
     **/
    public static String encrypt(String content, String key) {
        byte[] data = null;
        try {
            data = content.getBytes("UTF-8");
        } catch (Exception e) {
            e.printStackTrace();
        }
        data = encrypt(data, key, ivParameter);
        String result = byte2hex(data);
        return result;
    }

    /**
     * 加密字节数据
     **/
    public static byte[] encrypt(byte[] content, String password, String iv) {
        try {
            SecretKeySpec key = createKey(password);
            Cipher cipher = Cipher.getInstance(CipherMode);
            cipher.init(Cipher.ENCRYPT_MODE, key, createIV(iv));
            byte[] result = cipher.doFinal(content);
            return result;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 解密(输出结果为字符串)
     **/
    public static String decrypt(String content, String key) {
        byte[] data = null;
        try {
            data = hex2byte(content);
        } catch (Exception e) {
            e.printStackTrace();
        }
        data = decrypt(data, key, ivParameter);
        if (data == null)
            return null;
        String result = null;
        try {
            result = new String(data, "UTF-8");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return result;
    }

    /**
     * 解密字节数组
     **/
    public static byte[] decrypt(byte[] content, String password, String iv) {
        try {
            SecretKeySpec key = createKey(password);
            Cipher cipher = Cipher.getInstance(CipherMode);
            cipher.init(Cipher.DECRYPT_MODE, key, createIV(iv));
            byte[] result = cipher.doFinal(content);
            return result;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 字节数组转成16进制字符串
     **/
    public static String byte2hex(byte[] b) { // 一个字节的数，
        StringBuffer sb = new StringBuffer(b.length * 2);
        String tmp = "";
        for (int n = 0; n < b.length; n++) {
            // 整数转成十六进制表示
            tmp = (Integer.toHexString(b[n] & 0XFF));
            if (tmp.length() == 1) {
                sb.append("0");
            }
            sb.append(tmp);
        }
        return sb.toString().toUpperCase(); // 转成大写
    }

    /**
     * 将hex字符串转换成字节数组
     **/
    private static byte[] hex2byte(String inputString) {
        if (inputString == null || inputString.length() < 2) {
            return new byte[0];
        }
        inputString = inputString.toLowerCase();
        int l = inputString.length() / 2;
        byte[] result = new byte[l];
        for (int i = 0; i < l; ++i) {
            String tmp = inputString.substring(2 * i, 2 * i + 2);
            result[i] = (byte) (Integer.parseInt(tmp, 16) & 0xFF);
        }
        return result;
    }

    /**
     * 创建**
     **/
    private static SecretKeySpec createKey(String key) {
        byte[] data = null;
        if (key == null) {
            key = "";
        }
        StringBuffer sb = new StringBuffer(16);
        sb.append(key);
        while (sb.length() < 16) {
            sb.append("0");
        }
        if (sb.length() > 16) {
            sb.setLength(16);
        }
        try {
            data = sb.toString().getBytes("UTF-8");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return new SecretKeySpec(data, "AES");
    }

    private static IvParameterSpec createIV(String password) {
        byte[] data = null;
        if (password == null) {
            password = "";
        }
        StringBuffer sb = new StringBuffer(16);
        sb.append(password);
        while (sb.length() < 16) {
            sb.append("0");
        }
        if (sb.length() > 16) {
            sb.setLength(16);
        }
        try {
            data = sb.toString().getBytes("UTF-8");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return new IvParameterSpec(data);
    }

}

跟后台对接使用时的坑（当时后台时PHP）

1.JDK自带jar包不支持256位AES加密，需要到官网上下载下面两个jar包替换下面目录中的文件【文件目录：JAVA_HOME/jre/lib/security】：

2.实践中发现JAVA中IV【初始化向量不可以为32位，否则异常java.security.InvalidAlgorithmParameterException: Wrong IV length: must be 16 bytes long】

注：哪位大牛有解决IV是32位的方法告知小弟，苦逼的看了源码也没有研究明白。