/*
    * Copyright (C) 2012 The Guava Authors
    *
    * 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.
   */
  
  package com.google.common.hash;
  
  import com.google.caliper.BeforeExperiment;
  import com.google.caliper.Benchmark;
  import com.google.caliper.Param;
  
  import java.security.MessageDigest;
  
  /**
   * Benchmarks for comparing instance creation of {@link MessageDigest}s.
   *
   * @author Kurt Alfred Kluever
   */
  public class MessageDigestCreationBenchmark {
  
    @Param({"MD5", "SHA-1", "SHA-256", "SHA-512"})
    private String algorithm;
  
    private MessageDigest md;
  
    @BeforeExperiment void setUp() throws Exception {
      md = MessageDigest.getInstance(algorithm);
    }
  
    @Benchmark int getInstance(int reps) throws Exception {
      int retValue = 0;
      for (int i = 0; i < reps; i++) {
        retValue ^= MessageDigest.getInstance(algorithm).getDigestLength();
      }
      return retValue;
    }
  
    @Benchmark int clone(int reps) throws Exception {
      int retValue = 0;
      for (int i = 0; i < reps; i++) {
        retValue ^= ((MessageDigest) md.clone()).getDigestLength();
      }
      return retValue;
    }
  }