public class MyFirstApp
{
public static void main(String[] args)
{
System.out.print("Hello world")
}
}
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import java.security.InvalidKeyExceptionimport java.security.NoSuchAlgorithmExceptionimport javax.crypto.BadPaddingExceptionimport javax.crypto.Cipherimport javax.crypto.IllegalBlockSizeExceptionimport javax.crypto.KeyGeneratorimport javax.crypto.NoSuchPaddingExceptionimport javax.crypto.SecretKeypublic class JEncrytion{public static void main(String[] argv) {
try{ KeyGenerator keygenerator = KeyGenerator.getInstance("DES") SecretKey myDesKey = keygenerator.generateKey()
Cipher desCipher // Create the cipher
desCipher = Cipher.getInstance("DES/ECB/PKCS5Padding")
// Initialize the cipher for encryption
desCipher.init(Cipher.ENCRYPT_MODE, myDesKey) //sensitive information
byte[] text = "No body can see me".getBytes()
System.out.println("Text [Byte Format] : " + text)
System.out.println("Text : " + new String(text))
// Encrypt the text
byte[] textEncrypted = desCipher.doFinal(text)
System.out.println("Text Encryted : " + textEncrypted)
// Initialize the same cipher for decryption
desCipher.init(Cipher.DECRYPT_MODE, myDesKey) // Decrypt the text
byte[] textDecrypted = desCipher.doFinal(textEncrypted)
System.out.println("Text Decryted : " + new String(textDecrypted))
}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()
}
}
}
