Mega Code Archive
A bean that can be used to keep track of a counter
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/*
* Copyright (c) 2002-2003 by OpenSymphony
* All rights reserved.
*/
import java.io.Serializable;
/**
* A bean that can be used to keep track of a counter.
* <p/>
* Since it is an Iterator it can be used by the iterator tag
*
* @author Rickard Öberg (rickard@middleware-company.com)
* @version $Revision: 1282 $
* @see <related>
*/
public class Counter implements java.util.Iterator, Serializable {
boolean wrap = false;
// Attributes ----------------------------------------------------
long first = 1;
long current = first;
long interval = 1;
long last = -1;
public void setAdd(long addition) {
current += addition;
}
public void setCurrent(long current) {
this.current = current;
}
public long getCurrent() {
return current;
}
public void setFirst(long first) {
this.first = first;
current = first;
}
public long getFirst() {
return first;
}
public void setInterval(long interval) {
this.interval = interval;
}
public long getInterval() {
return interval;
}
public void setLast(long last) {
this.last = last;
}
public long getLast() {
return last;
}
// Public --------------------------------------------------------
public long getNext() {
long next = current;
current += interval;
if (wrap && (current > last)) {
current -= ((1 + last) - first);
}
return next;
}
public long getPrevious() {
current -= interval;
if (wrap && (current < first)) {
current += (last - first + 1);
}
return current;
}
public void setWrap(boolean wrap) {
this.wrap = wrap;
}
public boolean isWrap() {
return wrap;
}
public boolean hasNext() {
return ((last == -1) || wrap) ? true : (current <= last);
}
public Object next() {
return new Long(getNext());
}
public void remove() {
// Do nothing
}
}
///////////////////
/*
* Copyright (c) 2002-2003 by OpenSymphony
* All rights reserved.
*/
package com.opensymphony.webwork.util;
import junit.framework.TestCase;
/**
* User: plightbo
* Date: Jan 7, 2004
* Time: 7:55:35 PM
*/
public class CounterTest extends TestCase {
Counter c = new Counter();
public void testCurrentAfterNext() {
long next = c.getNext();
long current = c.getCurrent();
assertEquals(next + 1, current);
}
public void testCurrentBeforeNext() {
long current = c.getCurrent();
long next = c.getNext();
assertEquals(current, next);
}
public void testWrap() {
c.setWrap(true);
c.setLast(1);
long a = c.getNext();
long b = c.getNext();
assertEquals(1, a);
assertEquals(1, b);
}
}
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