sudo apt-get install mailx sendmail sudo apt-get install sharutils
[user@machine~]$ uuencode FileWithExtention FileWithExtention | mailx -s 'Subject' user_name@domain
import java.io.BufferedReader;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.util.ArrayList;
/**
*
* @author Shilpa Deshpande
*
*/
public class StringConcatenationPerformanceMeasurer {
private final int iteration;
private final String fileName;
class Measurement{
private long concat, plus, wrongBuilder, rightBuilder, stringBuffer;
/**
* @return The concat
*/
public long getConcat() {
return concat;
}
/**
* @param concat The concat to set
*/
public void setConcat(long concat) {
this.concat = concat;
}
/**
* @return The plus
*/
public long getPlus() {
return plus;
}
/**
* @param plus The plus to set
*/
public void setPlus(long plus) {
this.plus = plus;
}
/**
* @return The wrongBuilder
*/
public long getWrongBuilder() {
return wrongBuilder;
}
/**
* @param wrongBuilder The wrongBuilder to set
*/
public void setWrongBuilder(long wrongBuilder) {
this.wrongBuilder = wrongBuilder;
}
/**
* @return The rightBuilder
*/
public long getRightBuilder() {
return rightBuilder;
}
/**
* @param rightBuilder The rightBuilder to set
*/
public void setRightBuilder(long rightBuilder) {
this.rightBuilder = rightBuilder;
}
/**
* @return The stringBuffer
*/
public long getStringBuffer() {
return stringBuffer;
}
/**
* @param stringBuffer The stringBuffer to set
*/
public void setStringBuffer(long stringBuffer) {
this.stringBuffer = stringBuffer;
}
}
/**
* @param fileName
* @param iteration
*
*/
public StringConcatenationPerformanceMeasurer(int iteration, String fileName) {
this.iteration = iteration;
this.fileName = fileName;
}
/**
* @param args
*/
public static void main(String[] args) {
int iteration = 10;
String fileName = "StringConcatenationMeasurement.xls";
try {
System.out.println("Please enter number of iterations.");
BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
String readLine = in.readLine();
iteration = Integer.valueOf(readLine);
}
catch (IOException e) {
e.printStackTrace();
}
StringConcatenationPerformanceMeasurer instance = new StringConcatenationPerformanceMeasurer(
iteration, fileName);
try {
instance.checkStringConcatenationPerformance();
}
catch (Exception e) {
e.printStackTrace();
}
}
/**
* @throws Exception
*
*/
public void checkStringConcatenationPerformance() throws Exception {
ArrayList measurementList = new ArrayList();
for (int k = 0; k < iteration; k++) {
int limit = 5000;
String[] array = new String[limit];
for (int i = 0; i < limit; i++) {
array[i] = "e" + i + " ";
}
// Native String Concatenation using concat method
long t0 = System.currentTimeMillis();
String sbS = "";
for (int i = 0; i < limit; i++) {
sbS = sbS.concat(array[i]);
}
long t1 = System.currentTimeMillis();
//System.out.println("Final String using concat " + sbS);
sbS = null;
// Wrong String concatenation using StringBuilder
StringBuilder sb = new StringBuilder();
sbS = "";
for (int i = 0; i < limit; i++) {
sbS = (sb.append(sbS).append(array[i])).toString();
sb = new StringBuilder();
}
long t2 = System.currentTimeMillis();
//System.out.println("Final String - wrong usage of StringBuilder " + sbS);
sbS = null;
// Right String concatenation using StringBuilder
sb = new StringBuilder();
for (int i = 0; i < limit; i++) {
sb.append(array[i]);
}
sbS = sb.toString();
//System.out.println("Final String - right usage of StringBuilder " + sbS);
long t3 = System.currentTimeMillis();
sbS = null;
// String concatenation using +
sbS = "";
for (int i = 0; i < limit; i++) {
sbS = sbS + array[i];
}
long t4 = System.currentTimeMillis();
//System.out.println("Final String using + " + sbS);
sbS = null;
// String concatenation using StringBuffer
StringBuffer buffer = new StringBuffer();
for (int i = 0; i < limit; i++) {
buffer.append(array[i]);
}
sbS = buffer.toString();
//System.out.println("Final String using StringBuffer " + sbS);
long t5 = System.currentTimeMillis();
sbS = null;
System.out.println("=================================");
System.out.println("Native String Concatenation using concat method (Time in Milliseconds) " + (t1 - t0));
System.out.println("Wrong String concatenation using StringBuilder (Time in Milliseconds) " + (t2 - t1));
System.out.println("Right String concatenation using StringBuilder (Time in Milliseconds) " + (t3 - t2));
System.out.println("String concatenation using + (Time in Milliseconds) " + (t4 - t3));
System.out.println("String concatenation using StringBuffer (Time in Milliseconds) " + (t5 - t4));
System.out.println("=================================");
Measurement mm = new Measurement();
mm.setConcat((t1-t0));
mm.setWrongBuilder((t2-t1));
mm.setRightBuilder((t3-t2));
mm.setPlus((t4-t3));
mm.setStringBuffer((t5-t4));
measurementList.add(mm);
}
}
}
.