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缘由：

整理记录一下用Java进行AES加解密的示例代码，方便以后快速检索和使用。

正文：

参考解答：

常规的AES加解密：

package com.ixyzero.learn.utils;

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

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

public class DoCipherTest {

    public static String encrypt(String key, String initVector, String value) {
        try {
            IvParameterSpec iv = new IvParameterSpec(initVector.getBytes("UTF-8"));
            SecretKeySpec skeySpec = new SecretKeySpec(key.getBytes("UTF-8"), "AES");

            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
            cipher.init(Cipher.ENCRYPT_MODE, skeySpec, iv);

            byte[] encrypted = cipher.doFinal(value.getBytes());
            System.out.println("encrypted string: " + Base64.encodeBase64String(encrypted));

            return Base64.encodeBase64String(encrypted);
        } catch (Exception ex) {
            ex.printStackTrace();
        }

        return null;
    }

    public static String decrypt(String key, String initVector, String encrypted) {
        try {
            IvParameterSpec iv = new IvParameterSpec(initVector.getBytes("UTF-8"));
            SecretKeySpec skeySpec = new SecretKeySpec(key.getBytes("UTF-8"), "AES");

            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
            cipher.init(Cipher.DECRYPT_MODE, skeySpec, iv);

            byte[] original = cipher.doFinal(Base64.decodeBase64(encrypted));

            return new String(original);
        } catch (Exception ex) {
            ex.printStackTrace();
        }

        return null;
    }

    public static void main(String[] args) {
        String key = "Bar12345Bar12345"; // 128 bit key (16 chars)
        String initVector = "RandomInitVector"; // 16 bytes IV (16 chars)

        System.out.println(decrypt(key, initVector,
                encrypt(key, initVector, "Hello World")));
    }
}

在多线程项目中使用ThreadLocal进行优化：

package com.ixyzero.learn.utils;

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

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

/**
 * Created by ixyzero on 2018/8/16.
 */
public class ThreadLocalCipher {

    private static String sKey="Bar12345Bar12345";
    private static String ivParameter="RandomInitVector";

    private static final ThreadLocal<Cipher> encryptCiphers = new ThreadLocal<Cipher>() {
        @Override
        protected Cipher initialValue() {
            try {
                byte[] raw = sKey.getBytes("ASCII");
                SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
                IvParameterSpec iv = new IvParameterSpec(ivParameter.getBytes());

                Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
                cipher.init(Cipher.ENCRYPT_MODE, skeySpec, iv);
                return cipher;
            } catch (Exception e) {
                // ugly but necessary
                throw new RuntimeException(e);
            }
        }
    };

    private static final ThreadLocal<Cipher> decryptCiphers = new ThreadLocal<Cipher>() {
        @Override
        protected Cipher initialValue() {
            try {
                byte[] raw = sKey.getBytes("ASCII");
                SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
                IvParameterSpec iv = new IvParameterSpec(ivParameter.getBytes());

                Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
                cipher.init(Cipher.DECRYPT_MODE, skeySpec, iv);
                return cipher;
            } catch (Exception e) {
                // ugly but necessary
                throw new RuntimeException(e);
            }
        }
    };

    public static String encrypt(String data) {
        try {
            Cipher cipher = encryptCiphers.get();
            byte[] encrypted = cipher.doFinal(data.getBytes());
            
            System.out.println("encrypted string: " + Base64.encodeBase64String(encrypted));
            return Base64.encodeBase64String(encrypted);
        } catch (Exception ex) {
            ex.printStackTrace();
        }

        return null;
    }

    public static String decrypt(String encrypted) {
        try {
            Cipher cipher = decryptCiphers.get();
            byte[] original = cipher.doFinal(Base64.decodeBase64(encrypted));
            return new String(original);
        } catch (Exception ex) {
            ex.printStackTrace();
        }

        return null;
    }

    public static void main(String[] args) {
        String sourceData = "Hello World";
        String beEncrypted = encrypt(sourceData);
        String beDecrypted = decrypt(beEncrypted);

        System.out.println(beEncrypted);

        System.out.println(beDecrypted);
    }
}

参考链接：

• 用Java进行AES加解密#nice
• Cipher (Java Platform SE 7 )
• JAVA AES加密与解密
• 加密视频文件
• ==
• 创建和保持多个Cipher
• javax.crypto.Cipher 是线程安全的么？
• 高级加密标准AES的工作模式（ECB、CBC、CFB、OFB）

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