ExpGrowth.java

//
// Copyright (C) 2006 United States Government as represented by the
// Administrator of the National Aeronautics and Space Administration
// (NASA).  All Rights Reserved.
// 
// This software is distributed under the NASA Open Source Agreement
// (NOSA), version 1.3.  The NOSA has been approved by the Open Source
// Initiative.  See the file NOSA-1.3-JPF at the top of the distribution
// directory tree for the complete NOSA document.
// 
// THE SUBJECT SOFTWARE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY OF ANY
// KIND, EITHER EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING, BUT NOT
// LIMITED TO, ANY WARRANTY THAT THE SUBJECT SOFTWARE WILL CONFORM TO
// SPECIFICATIONS, ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR
// A PARTICULAR PURPOSE, OR FREEDOM FROM INFRINGEMENT, ANY WARRANTY THAT
// THE SUBJECT SOFTWARE WILL BE ERROR FREE, OR ANY WARRANTY THAT
// DOCUMENTATION, IF PROVIDED, WILL CONFORM TO THE SUBJECT SOFTWARE.
//
package gov.nasa.jpf.util;

public class ExpGrowth implements Growth {
  final float factor;
  final float sqFactor;
  final int plus;
  
  public ExpGrowth(float factor, int plus) {
    if (factor < 1.001F || factor > 100.F) {
      throw new IllegalArgumentException();
    }
    this.factor = factor;
    this.sqFactor = (float) Math.sqrt(factor);
    this.plus = plus;
  }
  
  public ExpGrowth(float factor) {
    this(factor,7);
  }
  
  public int grow(int oldSize, int minNewSize) {
    int newSize = (int)(factor * oldSize) + plus;
    if (newSize < minNewSize) {
      newSize = (int)(sqFactor * minNewSize) + plus;
    }
    return newSize;
  }
}