AES symmetric encryption and decryption process in Java _java

AES symmetric encryption and decryption code detailed introduction, for your reference, the specific content as follows  

Package demo.security;
Import java.io.IOException;
Import java.io.UnsupportedEncodingException;
Import java.security.InvalidKeyException;
Import java.security.NoSuchAlgorithmException;
Import Java.security.SecureRandom;
Import java.util.Base64;

Import Java.util.Scanner;
Import javax.crypto.BadPaddingException;
Import Javax.crypto.Cipher;
Import javax.crypto.IllegalBlockSizeException;
Import Javax.crypto.KeyGenerator;
Import javax.crypto.NoSuchPaddingException;
Import Javax.crypto.SecretKey;

Import Javax.crypto.spec.SecretKeySpec;
Import Sun.misc.BASE64Decoder;

Import Sun.misc.BASE64Encoder;  /* AES symmetric encryption and decryption/public class Symmetricencoder {/* * encryption * 1. Construct the key generator * 2. Initialize the key generator * 3 According to the Ecnoderules rule. Generate key *
      4. Create and initialize the cipher * 5. Content encryption * 6. Return string/public static string Aesencode (string encoderules,string content) {try {
      1. Construct the key generator, designated as AES algorithm, case-insensitive Keygenerator keygen=keygenerator.getinstance ("AES"); 2. Generate a 128-bit random source based on the Ecnoderules rule initialization key generator/, based on the bytes passed inArray Keygen.init (128, New SecureRandom (Encoderules.getbytes ()));
       3. Generate the original symmetric key Secretkey Original_key=keygen.generatekey ();
      4. Bytes array byte [] raw=original_key.getencoded () to obtain the original symmetric key;
       5. Generate AES Key Secretkey key=new Secretkeyspec (Raw, "AES") according to the byte array;
       6. According to the specified algorithm AES self-cipher Cipher cipher=cipher.getinstance ("AES");
      7. Initialize the cipher, the first parameter is encrypt (Encrypt_mode) or decrypt decrypt (decrypt_mode) operation, the second parameter is to use key Cipher.init (Cipher.encrypt_mode, key);
      8. Get the encrypted content of the byte array (here to set to Utf-8) otherwise the content if there are Chinese and English mixed in Chinese will be decrypted as garbled byte [] byte_encode=content.getbytes ("Utf-8");
     9. According to the initialization of the cipher-encryption: The Data encryption byte [] byte_aes=cipher.dofinal (Byte_encode); 10. Convert the encrypted data to a string//the package//workaround is not found in Base64encoder://The JRE System Library is first removed from the project's build path and the library JRE is added syste
      M Library, after recompiling everything is OK.
     String Aes_encode=new string (new Base64encoder (). Encode (Byte_aes));
    11. Return the string back to Aes_encode; catch (NoSuchAlgorithmException e) {E.printstaCktrace ();
    catch (Nosuchpaddingexception e) {e.printstacktrace ();
    catch (InvalidKeyException e) {e.printstacktrace ();
    catch (Illegalblocksizeexception e) {e.printstacktrace ();
    catch (Badpaddingexception e) {e.printstacktrace ();
    catch (Unsupportedencodingexception e) {e.printstacktrace ();     
  ////If there is a mistake, return nulll returns null; * * * Decryption process: * 1. With encryption 1-4 steps * 2. byte[the encrypted string into an array * 3. Decrypt the encrypted content/public static string Aesdncode ( String encoderules,string content) {try {//1. Construct key builder, specified as AES algorithm, case-insensitive Keygenerator keygen=keygenerator.get
      Instance ("AES"); 2. Generate a 128-bit random source based on the Ecnoderules rule initialization key generator/, according to the passed-in byte array keygen.init (128, New SecureRandom (Encoderules.getbytes ())
       );
       3. Generate the original symmetric key Secretkey Original_key=keygen.generatekey ();
      4. Bytes array byte [] raw=original_key.getencoded () to obtain the original symmetric key; 5. Generate AES Key Secretkey Key=new SECRETKEYSP based on byte arrayEC (Raw, "AES");
       6. According to the specified algorithm AES self-cipher Cipher cipher=cipher.getinstance ("AES");
      7. Initialize the cipher, the first parameter is encryption (Encrypt_mode) or decryption (Decrypt_mode) operation, the second parameter is the key Cipher.init (Cipher.decrypt_mode, key);
      8. Decode the encrypted and encoded content into a byte array byte [] byte_content= new Base64decoder (). Decodebuffer (content);
      * * Decryption/Byte [] byte_decode=cipher.dofinal (byte_content);
      String Aes_decode=new string (Byte_decode, "utf-8");
    return aes_decode;
    catch (NoSuchAlgorithmException e) {e.printstacktrace ();
    catch (Nosuchpaddingexception e) {e.printstacktrace ();
    catch (InvalidKeyException e) {e.printstacktrace ();
    catch (IOException e) {e.printstacktrace ();
    catch (Illegalblocksizeexception e) {e.printstacktrace ();
    catch (Badpaddingexception e) {e.printstacktrace ();     
  ////If there is a mistake, return nulll returns null; public static void Main (string[] args) {Symmetricencoder Se=neW Symmetricencoder ();
    Scanner scanner=new Scanner (system.in);
    * * * Encryption/SYSTEM.OUT.PRINTLN ("Use AES symmetric encryption, please enter the rules of Encryption");
    String Encoderules=scanner.next ();
    System.out.println ("Please enter the content to be encrypted:");
    String content = Scanner.next (); System.out.println ("+encoderules+" according to the input rule "encrypted cipher" is: "+se.
    
    Aesencode (encoderules, content));
     * * Decryption/SYSTEM.OUT.PRINTLN ("Using AES symmetric decryption, please enter the rules of encryption: (must be the same as encryption)");
    Encoderules=scanner.next ();
     System.out.println ("Please enter the content to decrypt (ciphertext):");
    Content = Scanner.next (); System.out.println ("+encoderules+" based on the rules entered) is decrypted with the following text: "+se."
  Aesdncode (encoderules, content));

 }

}

Test results:

Using AES symmetric encryption, enter the rules for encryption
Using AES symmetric encryption
Please enter the content to be encrypted:
Using AES symmetric encryption
The ciphertext that is encrypted using AES symmetric encryption according to the rules entered is: z0nwrnphghgxhn0cqjls58ycjhmcbfer33rws7lw+ay=
Using AES symmetric decryption, enter the rules for encryption: (must be the same as encryption)
Using AES symmetric encryption
Please enter the content to decrypt (ciphertext):
z0nwrnphghgxhn0cqjls58ycjhmcbfer33rws7lw+ay=
The plaintext that is decrypted using AES symmetric encryption based on the rules entered is: using AES symmetric encryption

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