如何用Java加密或解密文件？

Question

我想在java中加密和解密文件,我已经阅读了这个网址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人安全证书文件和private.pem文件,我复制这些文件并粘贴在当前目录中并按如下方式编写java代码,当我运行此操作时不执行加密或解密,请查看此信息并告诉我哪里出错了

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

你只是弄乱了你的文件.此代码使用从openssl生成的DER文件,如您链接的文章中所述:

    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);
    }