Online SHA256 Hash Generator

How to hash some string with sha256 in Java ? Does anybody know any free library for this ?

I'm building an automated process to produce extensions. Is there a code example of calculating the extension-ID directly and entirely bypassing interaction with the browser?

(I'm answering my own question, below.)

I once unpacked the Clash Royale APK to see its contents. Noteworthy was a file called "Fingerprint.JSON", which contains paths to sound files and an associated hash value. My question is, why the hash value can be found in this file. I can imagine that before starting the app a hash value of an audio file is created and compared with the hash value in the file "Fingerprint.JSON". But that would not make sense, because I could also exchange the hash value itself to implement my own sounds.

Maybe someone can explain why these hash values can be stored publicly without causing security risks?

I am looking to decrypt a string using AES, I tried multiple solution from SO but none of them helped and I was unable to get the solution. The android developer used Cipher to do it below is the code for that:-

    private static final byte[] initVector = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };    private static Cipher getAES_Cipher(int opmode) throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException,        InvalidAlgorithmParameterException {    IvParameterSpec iv = new IvParameterSpec(initVector);    SecretKeySpec skeySpec = new SecretKeySpec(Arrays.copyOfRange(getSHA(key), 0, 32), "AES");    Cipher cipher = Cipher.getInstance("AES/CFB/PKCS5PADDING");    cipher.init(opmode, skeySpec, iv);    return cipher;}

Similarly I tried using CryptoSwift to do it and below is the code I used to do it:-

extension String {func aesEncrypt(key: String, iv: String) throws -> String {    let data: Array<UInt8> = (self.data(using: .utf8)?.bytes)!    var key: Array<UInt8> = (key.data(using: .utf8)?.bytes)!    let iv: Array<UInt8> = (iv.data(using: .utf8)?.bytes)!    do {        let encrypted = try AES(key: key, blockMode: CFB(iv: iv), padding: .pkcs5).encrypt(data)        let encryptedData = Data(encrypted)        let decrypted = try AES(key: key, blockMode: CFB(iv: iv), padding: .pkcs5).decrypt(encrypted)        let decryptedData = Data(decrypted)        let str = String.init(data: decryptedData, encoding: .utf8)        print(str ?? String())        return encryptedData.base64EncodedString()    } catch {        print(error)        return "error"    }}func aesDecrypt(key: String, iv: String) throws -> String {    let data: Array<UInt8> = (Data(base64Encoded: self)?.bytes)!    let key: Array<UInt8> = (key.data(using: .utf8)?.bytes)!    let iv: Array<UInt8> = (iv.data(using: .utf8)?.bytes)!    do {        let decrypted = try AES(key: key.sha256(), blockMode: CFB(iv: iv), padding: .pkcs5).decrypt(data)        let decryptedData = Data(decrypted)        guard let value = String.init(data: decryptedData, encoding: .utf8) else {            return "error"        }        return value    } catch {        print(error)        return "error"    }}

}

and In ViewDidLoad() I called it like this:-

    let message = "My Encrypted String From The Server"    let test = try! message.aesDecrypt(key: "dfksjghlskjdfhglksjdfhglkjsdhfglkjhsfopweiurtypoweirutopiewrutgopiruegoijnsdeghsedrghesrerthigoererhehewthgewrhywertyweyweyewrtewrtyewihgoie", iv: "0000000000000000")    print(test)

One more thing I want to highlight when I pass the same iv as android which is "{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }" I am getting the error from the CryptoSwift library as invalidInitializationVector but when I pass iv: "0000000000000000" I am getting an error -->

  guard let value = String.init(data: decryptedData, encoding: .utf8) else {        return "error"    }

I believe it is something related to the iv that I am passing there.

Guys any help would be greatly appreciated!!

Thank You

I have to write method like this:

boolean isHash(String str){  ...}

Method should return true if input string is md5 hash or sha1 hash or sha256 hash.

Is it possible to implement such method ?