AESEncrypttUtil.java

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.security.GeneralSecurityException;
import java.util.Base64;

/**
 * 简单的 AES 对称加密
 *
 * @author mingcheng
 */
public class AESEncrypttUtil {
    private static final String KEY_ALGORITHM = "AES";
    private static AESEncrypttUtil instance;

    // 使用的时候请更改，需要 16 位长度
    final static String encryptionKey = "0123456789abcdef";

    private final Cipher cipher;

    private AESEncrypttUtil() throws GeneralSecurityException {
        cipher = Cipher.getInstance(KEY_ALGORITHM);
    }

    public static AESEncrypttUtil getInstance() throws GeneralSecurityException {
        if (instance == null) {
            instance = new AESEncrypttUtil();
        }
        return instance;
    }

    public String encrypt(String plainText, String encryptionKey) throws GeneralSecurityException, UnsupportedEncodingException {
        SecretKeySpec spec = new SecretKeySpec(encryptionKey.getBytes("UTF-8"), KEY_ALGORITHM);
        cipher.init(Cipher.ENCRYPT_MODE, spec);
        byte[] encryptedBytes = cipher.doFinal(plainText.getBytes());
        return Base64.getEncoder().encodeToString(encryptedBytes);
    }

    public String decrypt(String cipherText, String encryptionKey) throws GeneralSecurityException, IOException {
        SecretKeySpec spec = new SecretKeySpec(encryptionKey.getBytes("UTF-8"), KEY_ALGORITHM);
        cipher.init(Cipher.DECRYPT_MODE, spec);
        byte[] cipherTextBytes = Base64.getDecoder().decode(cipherText);
        byte[] decValue = cipher.doFinal(cipherTextBytes);
        return new String(decValue);
    }

    public String encrypt(String s) throws GeneralSecurityException, UnsupportedEncodingException {
        return encrypt(s, encryptionKey);
    }

    public String decrypt(String s) throws GeneralSecurityException, IOException {
        return decrypt(s, encryptionKey);
    }
}