Java Asymmetric Encryption

1  Packagetest;2 3 ImportJava.io.FileInputStream;4 ImportJava.io.FileOutputStream;5 ImportJava.io.ObjectInputStream;6 ImportJava.io.ObjectOutputStream;7 ImportJava.security.Key;8 ImportJava.security.KeyPair;9 ImportJava.security.KeyPairGenerator;Ten  One ImportJavax.crypto.Cipher; A  -  Public classTestCase { -  the      Public Static voidMain (string[] args)throwsException { - Publicenrypt (); - Privatedecrypt (); -  +     } -     //Encrypt +      Public Static voidPublicenrypt ()throwsexception{ A         //instantiate cryptographic tools using the RSA algorithm atCipher cipher=cipher.getinstance ("RSA"); -         //Instantiate key -Keypairgenerator keypairgenerator=keypairgenerator.getinstance ("RSA"); -         //get a pair of keys -KeyPair keypair=Keypairgenerator.generatekeypair (); -         //Get public key inKey publickey=keypair.getpublic (); -         //Get private key toKey privatekey=keypair.getprivate (); +         //encrypt with public key - Cipher.init (Cipher.encrypt_mode, publickey); the         byte[]result =cipher.dofinal ("Data Content". GetBytes ("UTF-8"))); *         //write the private key to the file $Savekey (Privatekey, "Zxx_private.key");Panax Notoginseng         //data storage after encryption -SaveData (Result, "Public_encryt.dat");  theSystem.out.println (NewString (Result, "UTF-8")); +     } A     //decryption the      Public Static voidPrivatedecrypt ()throwsexception{ +         //Instantiating cryptographic Tools -Cipher cipher=cipher.getinstance ("RSA"); $         //Get private key $Key Privatekey=readkey ("Zxx_private.key"); -         //get the encrypted information -         byte[] Src=readdata ("Public_encryt.dat"); the         //decrypt with private key - Cipher.init (Cipher.decrypt_mode, privatekey);Wuyi         byte[] result=cipher.dofinal (SRC); theSystem.out.println (NewString (Result, "UTF-8")); -     } Wu     //Save Data -      Public Static voidSaveData (byte[] result,string FileName)throwsexception{ AboutFileOutputStream fosdata=NewFileOutputStream (fileName); $ fosdata.write (result); - fosdata.close (); -     } -     //Save Key A      Public Static voidSavekey (Key key,string fileName)throwsexception{ +FileOutputStream foskey=NewFileOutputStream (fileName); theObjectOutputStream oossecretkey=NewObjectOutputStream (foskey); - Oossecretkey.writeobject (key); $ oossecretkey.close (); the Foskey.close ();  the     } the       //Read Key the      Public StaticKey ReadKey (String fileName)throwsexception{ -FileInputStream fiskey=NewFileInputStream (fileName); inObjectInputStream oiskey=NewObjectInputStream (fiskey); theKey key=(Key) oiskey.readobject (); the oiskey.close (); About fiskey.close (); the         returnkey; the     } the        //reading Data +      Public Static byte[] ReadData (String fileName)throwsexception{ -FileInputStream fisdat=NewFileInputStream (fileName); the         byte[] src=New byte[Fisdat.available ()];Bayi         intlen=fisdat.read (SRC); the         intTotal=0; the          while(total<src.length) { -total+=Len; -Len=fisdat.read (SRC, total, src.length-Total ); the         } the fisdat.close (); the          returnsrc; the     } -      the}

Java Asymmetric Encryption