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Copyright 2004, Colorado School of Mines and others.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
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    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.
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****************************************************************************/
package edu.mines.jtk.bench;

import java.util.ArrayList;

import edu.mines.jtk.util.Stopwatch;

/**
 * Benchmark ArrayList of primitives.
 * @author Dave Hale, Colorado School of Mines
 * @version 2005.02.17
 */
public class ArrayListBench {

  private static final int INITIAL_CAPACITY = 8;

  public static class FloatList {
    public int n;
    public float[] a = new float[INITIAL_CAPACITY];
    public void add(float f) {
      if (n==a.length) {
        float[] t = new float[2*a.length];
        System.arraycopy(a,0,t,0,n);
        a = t;
      }
      a[n++] = f;
    }
    public float[] trim() {
      float[] t = new float[n];
      System.arraycopy(a,0,t,0,n);
      return t;
    }
  }

  public static void main(String[] args) {
    double maxtime = 2;
    int n = 10000;
    double rate;
    for (int niter=0; niter<5; ++niter) {
      rate = benchArrayList(maxtime,n);
      System.out.println("ArrayList rate="+rate);
      rate = benchFloatList(maxtime,n);
      System.out.println("FloatList        rate="+rate);
    }
  }

  interface ListMaker {
    public void makeList(int n);
  }

  static double benchList(double maxtime, int n, ListMaker lm) {
    Stopwatch sw = new Stopwatch();
    sw.start();
    int niter;
    for (niter=0; sw.time() list = new ArrayList(INITIAL_CAPACITY);
        float f = 0.0f;
        for (int i=0; i