perf4j – Sample Snippets

 All samples depend on the Perf4J.

import org.perf4j.StopWatch;
import org.perf4j.log4j.Log4JStopWatch;
 
public class ArrayCopy {
 
private static int count = 200000;
private static void nArrayCopy() {
StopWatch stopWatch = new Log4JStopWatch();
int arrayFirst[]= new int[count];
int arraySecond[] = new int[count];
 
for(int i=0;i<count;i++) {
arrayFirst[i] = i;
}
 
for(int i=0; i<count ; i++) {
arraySecond[i] = arrayFirst[i];
}
 
for(int i=0; i<count ; i++) {
if(i/5000 == 0)
System.out.print(arraySecond[i]);
}
stopWatch.stop(“Normal Array Copy”);
 
}
 
private static void sArrayCopy() {
StopWatch stopWatch = new Log4JStopWatch();
int arrayFirst[]= new int[count];
int arraySecond[] = new int[count];
 
for(int i=0;i<count;i++) {
arrayFirst[i] = i;
}
 
 
System.arraycopy(arrayFirst, 0, arraySecond, 0, count);
 
for(int i=0; i<count ; i++) {
if(i/5000 == 0)
System.out.print(arraySecond[i]);
}
stopWatch.stop(“System Array Copy”);
 
}
 
public static void main(String[] args) {
nArrayCopy();
sArrayCopy();
}
}

import java.util.HashMap;
import java.util.Hashtable;
 
import org.perf4j.StopWatch;
import org.perf4j.log4j.Log4JStopWatch;
 
public class HMHT {
 
private static int count = 2000;
 
private static void hashMapMan() {
StopWatch stopWatch = new Log4JStopWatch();
HashMap hMan = new HashMap();
for(int i=0;i<count;i++) {
hMan.put(i, i);
}
stopWatch.stop(“HashMap”);
}
 
private static void hashTableMan() {
StopWatch stopWatch = new Log4JStopWatch();
Hashtable hTable = new Hashtable();
for(int i=0;i<count;i++) {
hTable.put(i, i);
}
stopWatch.stop(“HashTable”);
}
 
public static void main(String[] args) {
hashMapMan();
hashTableMan();
}
 
}

import org.perf4j.StopWatch;
import org.perf4j.log4j.Log4JStopWatch;
 
public class Primitivies {
 
private static int count = 20000;
 
private static void usingChar() {
StopWatch stopWatch = new Log4JStopWatch();
char val=0;
for(char i=0; i<count;i++) {
val = (char) (val + i);
}
stopWatch.stop(“Char”);
 
}
 
private static void usingShort() {
StopWatch stopWatch = new Log4JStopWatch();
short val=0;
for(short i=0; i<count;i++) {
val = (short) (val + i);
}
stopWatch.stop(“Short”);
}
 
private static void usingInt() {
StopWatch stopWatch = new Log4JStopWatch();
int val=0;
for(int i=0; i<count;i++) {
val = val + i;
}
stopWatch.stop(“Int”);
}
 
public static void main(String[] args) {
usingChar();
usingShort();
usingInt();
}
}

import org.perf4j.StopWatch;
import org.perf4j.log4j.Log4JStopWatch;
 
public class StringMan {
 
private static int count = 2000;
 
public static void usingString() {
StopWatch stopWatch = new Log4JStopWatch();
String output= new String();
for(int i=0;i<count;i++) {
output = output.concat(Integer.toString(i));
}
stopWatch.stop(“String”);
}
 
public static void usingStringBuffer() {
StopWatch stopWatch = new Log4JStopWatch();
StringBuffer output= new StringBuffer();
for(int i=0;i<count;i++) {
output = output.append(Integer.toString(i));
}
stopWatch.stop(“StringBuffer”);
}
 
public static void main(String[] args) {
usingString();
usingStringBuffer();
}
}

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Vector;
 
import org.perf4j.StopWatch;
import org.perf4j.log4j.Log4JStopWatch;
 
public class VALHM {
 
private static int count = 2000;
 
private static void vectorMan() {
StopWatch stopWatch = new Log4JStopWatch();
Vector vMan = new Vector();
for(int i=0;i<count;i++) {
vMan.add(i);
}
stopWatch.stop(“Vector”);
}
 
private static void hashMapMan() {
StopWatch stopWatch = new Log4JStopWatch();
HashMap hMan = new HashMap();
for(int i=0;i<count;i++) {
hMan.put(i, i);
}
stopWatch.stop(“HashMap”);
}
 
private static void arrayListMan() {
StopWatch stopWatch = new Log4JStopWatch();
ArrayList aMan = new ArrayList();
for(int i=0;i<count;i++) {
aMan.add(i);
}
stopWatch.stop(“ArrayList”);
}
 
public static void main(String[] args) {
vectorMan();
hashMapMan();
arrayListMan();
}
}