如何用Java加密或解密文件？

Question

我想用Java加密和解密文件，我已经阅读了这个URL http://www-
users.york.ac.uk/~mal503/lore/pkencryption.htm
，我得到了两个文件，即公共安全证书和私有安全证书文件和private.pem文件，我将这些文件复制并粘贴到当前目录中，并按如下所示编写Java代码，当我运行此文件时，未执行任何加密或解密操作，请查看并告诉我我哪里出了错

加密代码

File ecryptfile=new File("encrypt data");
                File publickeydata=new File("/publickey");
                File encryptmyfile=new File("/sys_data.db");
                File copycontent =new File("Copy Data");
                secure.makeKey();
                secure.saveKey(ecryptfile, publickeydata);
                secure.encrypt(encryptmyfile, copycontent);

解密代码

File ecryptfile=new File("encrypt data");
                File privateKeyFile=new File("/privatekey");
                File encryptmyfile=new File("/sys_data.db");
                File unencryptedFile =new File("unencryptedFile");
                try {
                                secure.loadKey(encryptmyfile, privateKeyFile);
                                secure.decrypt(encryptmyfile, unencryptedFile);
                        } catch (GeneralSecurityException e) {
                                // TODO Auto-generated catch block
                                e.printStackTrace();
                        } catch (IOException e) {
                                // TODO Auto-generated catch block
                                e.printStackTrace();
                        }

Answer 1

您只是混淆了文件。如您所链接的文章中所述，此代码使用从openssl生成的DER文件工作：

    FileEncryption secure = new FileEncryption();

    // Encrypt code
    {
        File encryptFile = new File("encrypt.data");
        File publicKeyData = new File("public.der");
        File originalFile = new File("sys_data.db");
        File secureFile = new File("secure.data");

        // create AES key
        secure.makeKey();

        // save AES key using public key
        secure.saveKey(encryptFile, publicKeyData);

        // save original file securely 
        secure.encrypt(originalFile, secureFile);
    }

    // Decrypt code
    {
        File encryptFile = new File("encrypt.data");
        File privateKeyFile = new File("private.der");
        File secureFile = new File("secure.data");
        File unencryptedFile = new File("unencryptedFile");

        // load AES key
        secure.loadKey(encryptFile, privateKeyFile);

        // decrypt file
        secure.decrypt(secureFile, unencryptedFile);
    }