Alternate Code in JavaScript for javax.crypto

I want to implement below code in JavaScript instead of using javax.crypto packages.

Below code will generate key using AES.

    KeyGenerator kgen;
    String key;
    try {
        kgen = KeyGenerator.getInstance("AES");
        kgen.init(128);
        SecretKey secretkey = kgen.generateKey();
        BASE64Encoder encode = new BASE64Encoder();
        key = encode.encode(secretkey.getEncoded());
    } catch (NoSuchAlgorithmException e) {
       // exceptionLogFile(e, null);
        e.printStackTrace();
        key = "Error@SecretKeyGeneration: No Such Algorith Exception. " + e.getMessage();
    } catch (Exception e) {
       // exceptionLogFile(e, null);
        e.printStackTrace();
        key = "Error@SecretKeyGeneration: " + e.getMessage();
    }
    return key;

This is perfectly working in Java, Now can anyone suggest me alternative in JavaScript.

I got to know about Crypto.js but how i can use here, not understanding.

For Encrypt and Decrypt, I am using "AES/ECB/PKCS5Padding" so is it compatible with the javascript code ?

Please help.

Thanks in advance.

An AES key consists simply of random bytes. So for a 128 byte key you can just do:

var key = CryptoJS.lib.WordArray.random(128/8);

and to encode it:

var keyBase64 = CryptoJS.enc.Base64.stringify(key);

Of course the key won't be identical to the one you generated before, you need to decode the previously generated base 64 encoded key to do that.

---

To use the key, use the explicit key parameters:

var encrypted = CryptoJS.AES.encrypt("Message", key, { mode: CryptoJS.mode.ECB});

PKCS#7 padding - which is identical to PKCS#5 padding - is already the default and ECB doesn't use an IV.