com.oracle.tools.util.ExponentialIterator Maven / Gradle / Ivy
/*
* File: ExponentialIterator.java
*
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* the Common Development and Distribution License 1.0 (the "License").
*
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*/
package com.oracle.tools.util;
import java.util.Iterator;
/**
* An {@link java.util.Iterator} over the
* Exponential sequence.
*
* Copyright (c) 2013. All Rights Reserved. Oracle Corporation.
* Oracle is a registered trademark of Oracle Corporation and/or its affiliates.
*
* @author Brian Oliver
*/
public class ExponentialIterator implements Iterator
{
/**
* The initial value;
*/
private double m_initial;
/**
* The rate a which growth should occur.
*/
private double m_rate;
/**
* The iteration.
*/
private long m_iteration;
/**
* Constructs a {@link ExponentialIterator}.
*
* @param initial the initial value (usually 0)
* @param percentage the rate of growth
*/
public ExponentialIterator(double initial,
double percentage)
{
m_initial = initial;
m_rate = 1 + (percentage / 100.0);
m_iteration = 0;
}
/**
* {@inheritDoc}
*/
@Override
public boolean hasNext()
{
return true;
}
/**
* {@inheritDoc}
*/
@Override
public Long next()
{
long result;
if (m_iteration == 0)
{
result = Math.round(m_initial);
}
else
{
result = Math.round(m_initial + Math.pow(m_rate, m_iteration - 1));
}
m_iteration++;
return result;
}
/**
* {@inheritDoc}
*/
@Override
public void remove()
{
throw new UnsupportedOperationException("Can't remove from a " + this.getClass().getName());
}
}