玩了一下AES加密解密

我將自己寫的程式碼貼上來，這是很簡短的程式，希望高手能稍加提點我自己不足之處。

import javax.crypto.Cipher;

import javax.crypto.spec.SecretKeySpec;



public class TestAES {



    public static byte[] encrypt( byte[] msg ) throws Exception {

        byte[] key = "vegafish12345678".getBytes();  // key 長度 = 16

        return encrypt( key, msg );

    }

    

    public static byte[] encrypt( byte[] key, byte[] msg ) throws Exception {

        if ( key.length != 16 ) {

            throw new IllegalArgumentException( "Key length should be 16." );

        }

        SecretKeySpec spec = new SecretKeySpec( key, "AES" );

        Cipher cipher = Cipher.getInstance( "AES" );

        cipher.init( Cipher.ENCRYPT_MODE, spec );

        return cipher.doFinal( msg );

    }



    public static byte[] decrypt( byte[] msg ) throws Exception {

        byte[] key = "vegafish12345678".getBytes();  // key 長度 = 16

        return decrypt( key, msg );

    }



    public static byte[] decrypt( byte[] key, byte[] msg ) throws Exception {

        if ( key.length != 16 ) {

            throw new IllegalArgumentException( "Key length should be 16." );

        }

        SecretKeySpec spec = new SecretKeySpec( key, "AES" );

        Cipher cipher = Cipher.getInstance( "AES" );

        cipher.init( Cipher.DECRYPT_MODE, spec );

        return cipher.doFinal( msg );

    }



    public static void main( String[] args ) throws Exception {

        String msg = "要被加密的訊息, the text would be encrypted.";

    

        System.out.println( "原始String  : " + msg );

        System.out.println( "byte[]加密後: " + new String( encrypt( msg.getBytes() ) ) );

        System.out.println( "byte[]解密後: " + new String( decrypt( encrypt( msg.getBytes() ) ) ) );

    }



}