java AES和RSA加密UTIL

以下是 Java 中使用 AES 和 RSA 加密的示例代码：

AES 加密：

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
import java.util.Base64;

public class AESUtil {
    private static final String ALGORITHM = "AES";
    private static final String CIPHER_ALGORITHM = "AES/ECB/PKCS5Padding";
    private static final byte[] KEY = "your-secret-key".getBytes();

    public static String encrypt(String input) throws Exception {
        SecretKeySpec secretKeySpec = new SecretKeySpec(KEY, ALGORITHM);
        Cipher cipher = Cipher.getInstance(CIPHER_ALGORITHM);
        cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec);
        byte[] encrypted = cipher.doFinal(input.getBytes());
        return Base64.getEncoder().encodeToString(encrypted);
    }
}

RSA 加密：

import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import javax.crypto.Cipher;
import java.util.Base64;

public class RSAUtil {
    private static final String ALGORITHM = "RSA";
    private static final String CIPHER_ALGORITHM = "RSA/ECB/PKCS1Padding";
    private static final int KEY_SIZE = 2048;

    public static KeyPair generateKeyPair() throws Exception {
        KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance(ALGORITHM);
        keyPairGenerator.initialize(KEY_SIZE);
        return keyPairGenerator.generateKeyPair();
    }

    public static String encrypt(String input, PublicKey publicKey) throws Exception {
        Cipher cipher = Cipher.getInstance(CIPHER_ALGORITHM);
        cipher.init(Cipher.ENCRYPT_MODE, publicKey);
        byte[] encrypted = cipher.doFinal(input.getBytes());
        return Base64.getEncoder().encodeToString(encrypted);
    }

    public static PrivateKey decodePrivateKey(String key) throws Exception {
        byte[] keyBytes = Base64.getDecoder().decode(key.getBytes());
        PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(ALGORITHM);
        return keyFactory.generatePrivate(keySpec);
    }

    public static PublicKey decodePublicKey(String key) throws Exception {
        byte[] keyBytes = Base64.getDecoder().decode(key.getBytes());
        X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(ALGORITHM);
        return keyFactory.generatePublic(keySpec);
    }
}

注意：这些代码只是示例，并不是完整且安全的加密实现。在实际使用中，需要根据具体的需求和安全要求进行修改和优化。