Java tutorial
//package com.java2s; import javax.crypto.KeyGenerator; import javax.crypto.SecretKey; import java.security.NoSuchAlgorithmException; public class Main { public static byte[] initKey() throws NoSuchAlgorithmException { KeyGenerator keyGen = KeyGenerator.getInstance("AES"); keyGen.init(256); //192 256 SecretKey secretKey = keyGen.generateKey(); return secretKey.getEncoded(); } }