Mega Code Archive
A basic performance test for a couple of common operations 2
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/* ===========================================================
* JFreeChart : a free chart library for the Java(tm) platform
* ===========================================================
*
* (C) Copyright 2000-2004, by Object Refinery Limited and Contributors.
*
* Project Info: http://www.jfree.org/jfreechart/index.html
*
* This library is free software; you can redistribute it and/or modify it under the terms
* of the GNU Lesser General Public License as published by the Free Software Foundation;
* either version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
* without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License along with this
* library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
* Boston, MA 02111-1307, USA.
*
* [Java is a trademark or registered trademark of Sun Microsystems, Inc.
* in the United States and other countries.]
*
* -----------------
* Performance2.java
* -----------------
* (C) Copyright 2002-2004, by Object Refinery Limited.
*
* Original Author: David Gilbert (for Object Refinery Limited).
* Contributor(s): -;
*
* $Id: Performance2.java,v 1.10 2004/04/26 19:12:00 taqua Exp $
*
* Changes (since 11-Oct-2002)
* ---------------------------
* 11-Oct-2002 : Fixed errors reported by Checkstyle (DG);
*
*/
package org.jfree.chart.demo;
import java.util.Date;
/**
* A basic performance test for a couple of common operations.
*
*/
public class Performance2 {
/** A double primitive. */
private double primitive = 42.0;
/** A number object. */
private Number object = new Double(42.0);
/**
* Default constructor.
*/
public Performance2() {
super();
}
/**
* Just use double value - should be fast.
*
* @return the double value.
*/
public double getPrimitive() {
return this.primitive;
}
/**
* Creates a Number object every time the primitive is accessed - should be really slow.
*
* @return creates and returns a Number object.
*/
public Number getPrimitiveAsObject() {
return new Double(this.primitive);
}
/**
* Returns the object - caller has to use doubleValue() method.
*
* @return an existing Number object.
*/
public Number getObject() {
return this.object;
}
/**
* Returns a double value generated from the Object - should be similar to previous method,
* but is not!
*
* @return the doubleValue() for the Number.
*/
public double getObjectAsPrimitive() {
return this.object.doubleValue();
}
/**
* Cycles through accessing the primitive.
*
* @param count the number of times to access.
*/
public void getPrimitiveLoop(final int count) {
double d = 0.0;
for (int i = 0; i < count; i++) {
d = getPrimitive();
}
System.out.println(d);
}
/**
* Cycles through accessing the primitive as an object.
*
* @param count the number of times to access.
*/
public void getPrimitiveAsObjectLoop(final int count) {
double d = 0.0;
for (int i = 0; i < count; i++) {
d = getPrimitiveAsObject().doubleValue();
}
System.out.println(d);
}
/**
* Cycles through accessing the object as a primitive.
*
* @param count the number of times to access.
*/
public void getObjectAsPrimitiveLoop(final int count) {
double d = 0.0;
for (int i = 0; i < count; i++) {
d = getObjectAsPrimitive();
}
System.out.println(d);
}
/**
* Cycles through accessing the object.
*
* @param count the number of times to access.
*/
public void getObjectLoop(final int count) {
double d = 0.0;
for (int i = 0; i < count; i++) {
d = getObject().doubleValue();
}
System.out.println(d);
}
/**
* Outputs the current status to the console.
*
* @param label the label.
* @param start the start time.
* @param end the end time.
*/
public void status(final String label, final Date start, final Date end) {
final long elapsed = end.getTime() - start.getTime();
System.out.println(label + start.getTime() + "-->" + end.getTime() + " = " + elapsed);
}
/**
* The starting point for the performance test.
*
* @param args ignored.
*/
public static void main(final String[] args) {
final Performance2 performance = new Performance2();
final int count = 10000000;
for (int repeat = 0; repeat < 3; repeat++) { // repeat a few times just to make
// sure times are consistent
final Date s1 = new Date();
performance.getPrimitiveLoop(count);
final Date e1 = new Date();
performance.status("getPrimitive() : ", s1, e1);
final Date s2 = new Date();
performance.getPrimitiveAsObjectLoop(count);
final Date e2 = new Date();
performance.status("getPrimitiveAsObject() : ", s2, e2);
final Date s3 = new Date();
performance.getObjectLoop(count);
final Date e3 = new Date();
performance.status("getObject() : ", s3, e3);
final Date s4 = new Date();
performance.getObjectAsPrimitiveLoop(count);
final Date e4 = new Date();
performance.status("getObjectAsPrimitive() : ", s4, e4);
System.out.println("-------------------");
}
}
}
jfreechart-1.0.0-rc1.zip( 3,559 k)
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