com.google.gwt.benchmarks.client.IntRange Maven / Gradle / Ivy
/*
* Copyright 2007 Google 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.
*/
package com.google.gwt.benchmarks.client;
/**
* Iterates over a start and end value by a stepping function. Typically used by
* benchmarks to supply a range of values over an integral parameter, such as
* size or length.
*/
public class IntRange implements Iterable {
/**
* Implementation of the Iterator.
*
*/
private static class IntRangeIterator extends RangeIterator {
int end;
Operator operator;
int step;
int value;
IntRangeIterator(IntRange r) {
this.value = r.start;
this.end = r.end;
this.operator = r.operator;
if (operator == null) {
throw new IllegalArgumentException("operator must be \"*\" or \"+\"");
}
this.step = r.step;
}
public boolean hasNext() {
return value <= end;
}
public Integer next() {
int currentValue = value;
value = step();
return currentValue;
}
public int step() {
if (operator == Operator.MULTIPLY) {
return value * step;
} else {
return value + step;
}
}
}
int end;
Operator operator;
int start;
int step;
/**
* Creates a new range that produces Iterators which begin at
* start, end at end and increment by the
* stepping function described by operator and
* step.
*
* @param start Initial starting value, inclusive.
* @param end Ending value, inclusive.
* @param operator The function used to step.
* @param step The amount to step by, for each iteration.
*/
public IntRange(int start, int end, Operator operator, int step) {
this.start = start;
this.end = end;
this.operator = operator;
this.step = step;
if (step <= 0) {
throw new IllegalArgumentException("step must be > 0");
}
}
public IntRangeIterator iterator() {
return new IntRangeIterator(this);
}
}