java实现rsa算法加解密完整代码

很高兴能为您解答问题！以下是Java实现RSA算法加解密的完整代码：

import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.PrivateKey;
import java.security.PublicKey;
import javax.crypto.Cipher;

public class RSAEncryptionExample {
    
    public static void main(String[] args) throws Exception {
        String plainText = "Hello, world!";
        
        // Generate public and private keys
        KeyPair keyPair = generateKeyPair();
        PublicKey publicKey = keyPair.getPublic();
        PrivateKey privateKey = keyPair.getPrivate();
        
        // Encrypt the plaintext using the public key
        byte[] cipherText = encrypt(plainText, publicKey);
        
        // Decrypt the ciphertext using the private key
        String decryptedText = decrypt(cipherText, privateKey);
        
        // Print the original plaintext, the encrypted ciphertext,
        // and the decrypted plaintext to the console
        System.out.println("Original plaintext: " + plainText);
        System.out.println("Encrypted ciphertext: " + new String(cipherText));
        System.out.println("Decrypted plaintext: " + decryptedText);
    }
    
    public static KeyPair generateKeyPair() throws Exception {
        KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
        keyPairGenerator.initialize(2048);
        return keyPairGenerator.generateKeyPair();
    }
    
    public static byte[] encrypt(String plainText, PublicKey publicKey) throws Exception {
        Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
        cipher.init(Cipher.ENCRYPT_MODE, publicKey);
        return cipher.doFinal(plainText.getBytes());
    }
    
    public static String decrypt(byte[] cipherText, PrivateKey privateKey) throws Exception {
        Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
        cipher.init(Cipher.DECRYPT_MODE, privateKey);
        return new String(cipher.doFinal(cipherText));
    }
}

希望这个代码能够帮助您！如果您有其他问题，请随时提出，我将尽力为您解答。