1 packagecom.test;2
3 importjava.io.File;4 importjava.io.FileInputStream;5 importjava.io.FileOutputStream;6 importjava.io.InputStream;7 importjava.io.OutputStream;8 importjava.security.KeyPair;9 importjava.security.KeyPairGenerator;10 importjava.security.NoSuchAlgorithmException;11 importjava.security.interfaces.RSAPrivateKey;12 importjava.security.interfaces.RSAPublicKey;13 importjavax.crypto.Cipher;14
15 public classRSAEncrypt {16
17 staticKeyPairGenerator keyPairGen;18
19 staticKeyPair keyPair;20
21 staticRSAPrivateKey privateKey;22
23 staticRSAPublicKey publicKey;24
25 static{26 try{27 keyPairGen = KeyPairGenerator.getInstance("RSA");28 keyPairGen.initialize(512);29 keyPair =keyPairGen.generateKeyPair();30 //Generate keys
31 privateKey =(RSAPrivateKey) keyPair.getPrivate();32 publicKey =(RSAPublicKey) keyPair.getPublic();33 } catch(NoSuchAlgorithmException e) {34 //TODO Auto-generated catch block
35 e.printStackTrace();36 }37 }38
39 public static voidmain(String[] args) {40 RSAEncrypt encrypt = newRSAEncrypt();41 File file = new File("C:\\Users\\張洋\\Desktop\\logo1.png");42 File newFile = new File("C:\\Users\\張洋\\Desktop\\logo已加密");43 encrypt.encryptFile(encrypt, file, newFile);44 File file1 = new File("C:\\Users\\張洋\\Desktop\\logo已加密");45 File newFile1 = new File("C:\\Users\\張洋\\Desktop\\logo已解密.png");46 encrypt.decryptFile(encrypt, file1, newFile1);47 }48
49 public voidencryptFile(RSAEncrypt encrypt, File file, File newFile) {50 try{51 InputStream is = newFileInputStream(file);52 OutputStream os = newFileOutputStream(newFile);53
54 byte[] bytes = new byte[53];55 while (is.read(bytes) > 0) {56 byte[] e =encrypt.encrypt(RSAEncrypt.publicKey, bytes);57 bytes = new byte[53];58 os.write(e, 0, e.length);59 }60 os.close();61 is.close();62 System.out.println("write success");63 } catch(Exception e) {64 e.printStackTrace();65 }66 }67
68 public voiddecryptFile(RSAEncrypt encrypt, File file, File newFile) {69 try{70 InputStream is = newFileInputStream(file);71 OutputStream os = newFileOutputStream(newFile);72 byte[] bytes1 = new byte[64];73 while (is.read(bytes1) > 0) {74 byte[] de =encrypt.decrypt(RSAEncrypt.privateKey, bytes1);75 bytes1 = new byte[64];76 os.write(de, 0, de.length);77 }78 os.close();79 is.close();80 System.out.println("write success");81
82 } catch(Exception e) {83 e.printStackTrace();84 }85 }86
87
88
93 protected byte[] encrypt(RSAPublicKey publicKey, byte[] obj) {94 if (publicKey != null) {95 try{96 Cipher cipher = Cipher.getInstance("RSA");97 cipher.init(Cipher.ENCRYPT_MODE, publicKey);98 returncipher.doFinal(obj);99 } catch(Exception e) {100 e.printStackTrace();101 }102 }103 return null;104 }105
106
107
112 protected byte[] decrypt(RSAPrivateKey privateKey, byte[] obj) {113 if (privateKey != null) {114 try{115 Cipher cipher = Cipher.getInstance("RSA");116 cipher.init(Cipher.DECRYPT_MODE, privateKey);117 returncipher.doFinal(obj);118 } catch(Exception e) {119 e.printStackTrace();120 }121 }122 return null;123 }124 }