How does JUnit work?

JUnit is using for unit testing.

Note that this is not a replacement to the Testing phase, which is a part of the Software Development Life Cycle. (SDLC)

This is normally use for test programms, from the programmers perspective.

If u can do testing eith JUnit u can definitly improve the quality of your source-code. (So, less # of errors will be getting from the regular testing phase)

This is an sample example:

Assume this is a small program of doing calculations,

(This is what a programmer write normally)

public class Cal{

public int add(int a,int b){

return a+b;

}

public int sub(int a,int b){

return a-b;

}

public int mult(int a,int b){

return a*b;

}

public int div(int a,int b){

return a/b;

}

}

When use JUnit, the test-code will look like this;

(This should write in addition to the Cal.java)

import junit.framework.TestCase;

public class CalTest extends TestCase{

private Cal cal;

//initialize the fixture

public void setUp(){

cal = new Cal();

}

//clean up

public void tearDown(){

//do clean ups

}

//test method for add

public void testAdd(){

int x=4,y=6;

int actual = cal.add(x,y);

int expected = 10;

assertEquals(expected,actual);

}

//test method for sub

public void testSub(){

int x=4,y=6;

int actual = cal.sub(x,y);

int expected = -2;

assertEquals(expected,actual);

}

//test method for mult

public void testMult(){

int x=4,y=6;

int actual = cal.mult(x,y);

int expected = 24;

assertEquals(expected,actual);

}

//test method for div

public void testDiv(){

int x=6,y=3;

int actual = cal.div(x,y);

int expected = 2;

assertEquals(expected,actual);

}

This is an additional overhead to the programmer... but sometimes it may worth of doing it

Visit www.junit.org

jugpa at 2007-7-14 18:22:21 >