Here you can find the source of getHashInstance(final String alg)
static MessageDigest getHashInstance(final String alg)
//package com.java2s; /*//w ww .j a v a 2s . co m Copyright 2011, Lightbox Technologies, Inc Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. */ import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; public class Main { static MessageDigest getHashInstance(final String alg) { MessageDigest hash; try { hash = MessageDigest.getInstance(alg); } catch (NoSuchAlgorithmException ex) { throw new RuntimeException("As if " + alg + " isn't going to be implemented, bloody Java tossers"); } return hash; } }