针对Java + OpenPGP的建议？

针对Java + OpenPGP的建议，您可以使用以下方法来实现加密和解密功能：

加密：使用Java的Bouncy Castle库来实现OpenPGP加密。Bouncy Castle是一个广泛使用的加密和解密库，支持多种加密算法，包括PGP。您可以使用以下代码来加密数据：

import org.bouncycastle.openpgp.*;
import org.bouncycastle.openpgp.operator.jcajce.*;

public byte[] encrypt(byte[] data, PGPPublicKey publicKey) throws IOException, PGPException {
    ByteArrayOutputStream encryptedData = new ByteArrayOutputStream();
    PGPEncryptedDataGenerator encryptedDataGenerator = new PGPEncryptedDataGenerator(
            new JcePGPDataEncryptorBuilder(PGPEncryptedData.CAST5).setWithIntegrityPacket(true).setSecureRandom(new SecureRandom()).setProvider("BC"));
    encryptedDataGenerator.addMethod(publicKey);

    OutputStream encryptedOut = encryptedDataGenerator.open(encryptedData, new byte[4096]);
    encryptedOut.write(data);
    encryptedOut.close();

    return encryptedData.toByteArray();
}

解密：使用Java的Bouncy Castle库来实现OpenPGP解密。您可以使用以下代码来解密数据：

import org.bouncycastle.openpgp.*;
import org.bouncycastle.openpgp.operator.jcajce.*;

public byte[] decrypt(byte[] encryptedData, PGPSecretKey secretKey, char[] passphrase) throws IOException, PGPException {
    PGPEncryptedDataList encryptedDataList = new PGPEncryptedDataList(encryptedData);
    PGPPrivateKey privateKey = secretKey.extractPrivateKey(new JcePBESecretKeyDecryptorBuilder().setProvider("BC").build(passphrase));
    InputStream decryptedData = encryptedDataList.getDataStream(new JcePublicKeyKeyDataDecryptorFactoryBuilder().setProvider("BC").build(privateKey));

    ByteArrayOutputStream decryptedOut = new ByteArrayOutputStream();
    byte[] buffer = new byte[4096];
    int bytesRead;
    while ((bytesRead = decryptedData.read(buffer)) != -1) {
        decryptedOut.write(buffer, 0, bytesRead);
    }

    return decryptedOut.toByteArray();
}