多亏了你们的帮助，我终于发明了一种新的算法，目前看来它还可以工作。我会在下面链接让我知道你的想法，并提前为变量名道歉，我正在努力。

/*
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package oserver;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.security.Key;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.RSAPublicKeySpec;
import java.io.File;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.math.BigInteger;
import java.security.InvalidKeyException;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.RSAPrivateKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.Base64;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;

/**
 *
 * @author sgmud
 */
public class Encryption {

    public static PrivateKey privateKey;
    public static PublicKey publicKey;

    public void KeyGeneration() throws NoSuchAlgorithmException{
        KeyPairGenerator Generator = KeyPairGenerator.getInstance("RSA"); // Creat the Generator object with RSA
        Generator.initialize(1024); // Set the generator to make the 2048 bit key
        KeyPair Pair = Generator.genKeyPair(); // Generate the key pair
        publicKey = Pair.getPublic(); // Set the Public Key
        privateKey = Pair.getPrivate(); // Set the private Key

        System.out.println(Base64.getEncoder().encodeToString(publicKey.getEncoded()));
        System.out.println(Base64.getEncoder().encodeToString(privateKey.getEncoded()));

    }

    public void writeToFile(String filePath, byte[] key) throws IOException{
        File fileToWriteto = new File(filePath);
        fileToWriteto.getParentFile().mkdirs();
        FileOutputStream FoutputStream = new FileOutputStream(fileToWriteto);
        FoutputStream.write(key);
        FoutputStream.flush();
        FoutputStream.close();

    }

    public static PublicKey getPublicKey(String base64PublicKey){
        PublicKey publicKey = null;
        try{
            X509EncodedKeySpec KeySpec = new X509EncodedKeySpec(Base64.getDecoder().decode(base64PublicKey.getBytes()));
            KeyFactory Keyfact = KeyFactory.getInstance("RSA");
            publicKey = Keyfact.generatePublic(KeySpec);
            return publicKey;   
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        } catch (InvalidKeySpecException e) {
            e.printStackTrace();
        }
        return publicKey;
    }

    public byte[] Encrypt(String data, String publicKey) throws InvalidKeyException, NoSuchAlgorithmException, NoSuchPaddingException, IOException, BadPaddingException, IllegalBlockSizeException{

        Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
        cipher.init(Cipher.ENCRYPT_MODE, getPublicKey(publicKey));
        return cipher.doFinal(data.getBytes());
}

    public static PrivateKey getPrivateKey(String base64PrivateKey){
        PrivateKey privateKey = null;
        PKCS8EncodedKeySpec keySpec = new  PKCS8EncodedKeySpec(Base64.getDecoder().decode(base64PrivateKey.getBytes()));
        KeyFactory Kfact = null;
        try{

            Kfact = Kfact.getInstance("RSA");

        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace(); 
        }
        try{
            privateKey = Kfact.generatePrivate(keySpec);
        }catch(InvalidKeySpecException e){
            e.printStackTrace();
        }
        return privateKey;
    }

    public static String decrypt(byte[] data, PrivateKey privateKey) throws InvalidKeyException, NoSuchAlgorithmException, NoSuchPaddingException, IOException, BadPaddingException, IllegalBlockSizeException{

        Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
        cipher.init(Cipher.DECRYPT_MODE, privateKey);
        return new String(cipher.doFinal(data));
} 

    public static String Decrypt(String data, String base64PrivateKey) throws InvalidKeyException, NoSuchAlgorithmException, NoSuchPaddingException, IOException, BadPaddingException, IllegalBlockSizeException{
        return decrypt(Base64.getDecoder().decode(data.getBytes()), getPrivateKey(base64PrivateKey));
} 

}

直接的问题是您正在写入文件并从资源中读取。资源是一个只读文件，包含在java源文件中（例如gui应用程序中的图标）。
您应该使用 key.getEncoded() 相反。然后您可以使用相同的密钥工厂，但是 X509EncodedKeySpec 读回公钥 PKCS8EncodedKeySpec 私钥。
请注意，您当前正在为私钥编写模数和私钥指数。在实践中，还编写了中国剩余定理（crt）参数，这些参数可以用来加速rsa私钥运算。