SELENIUM LISTENERS:

LISTENERS:

There are two main listeners i.e. WebDriver Listeners and TestNG Listeners.

TestNG Listeners:

 In TestNG, there are several listeners that act as interfaces to modify the default TestNG's behaviors.

As the name suggests Listeners "listen" to the event defined in the selenium script and behave accordingly. It allows customizing TestNG reports or logs.

With the help of Listeners we can modify the behaviour of TestNG. We can create logs with the help of listeners in TestNG. It is used in selenium by implementing Listeners Interface. It is required for logging purpose.

Types of Listeners in TestNG

There are many types of listeners which allows you to change the TestNG's behavior.

1.IAnnotationTransformer

2.IAnnotationTransformer2

3.IConfigurable

4.IConfigurationListener

5.IExecutionListener

6.IHookable

7.IInvokedMethodListener

8.IInvokedMethodListener2

9.IMethodInterceptor

10.IReporter

11.ISuiteListener

12.ITestListener

All Interfaces are called TestNG Listeners. These interfaces are used in selenium to generate logs or customize the testing reports.

ITestListener ( I ) :

When running TestNG tests, one could want to perform some common actions – after each test has finished successfully, after each failed test, after each skipped test, or after all the tests have finished running, no matter their result.To apply such a common behavior to a group of tests, a custom listener can be created, that implements TestNG’sITestListener interface.

There are two types of methods to implement: a set of them are related to a single test’s run (onTestStart, onTestSuccess, onTestFailure, onTestSkipped, onTestFailedButWithinSuccessPercentage), the other to the whole suite’s run (onStart, onFinish).

These methods, depending on their type, have a parameter passed to them: result, which is of type ITestResult – for the test run, and context, which is of type ITestContext, for the suite run.

These types offer different information, for example: ITestResult can tell you when a test began to run, when it finished running, what status the test had (whether failed, passed), whereas ITestContext can tell you the list of all the passed tests, all the failed ones, and so on.

Methods in ITestListener are following below ,

1.OnStart( )- OnStart method is called when any Test starts.

sysntax: public void onTestStart(ITestResult result)

2.onTestSuccess( )- onTestSuccess method is called on the success of any Test.

syntax: public void onTestSuccess(ITestResult result)

3.onTestFailure( )- onTestFailure method is called on the failure of any Test.

syntax: public void onTestFailure(ITestResult result)

4.onTestSkipped( )- onTestSkipped method is called on skipped of any Test.

syntax: public void onTestSkipped(ITestResult result)

5.onTestFailedButWithinSuccessPercentage( )- method is called each time Test fails but is within success percentage.

syntax: public void onTestFailedButWithinSuccessPercentage(ITestResult result)

6.onFinish( )- onFinish method is called after all Tests are executed.

syntax: public void onFinish(ITestContext context)

Example:

1.Write out Test Cases in ListenerDemo.java file

package com.rameshsoft.rameshselenium;

import org.testng.annotations.Listeners;

import org.openqa.selenium.WebDriver;

import org.openqa.selenium.firefox.FirefoxDriver;

import org.testng.annotations.Test;

@Listeners(com.rameshsoft.rameshselenium.Listeners.class)

public class ListenerClassDemo {

          @Test

          public void method()

          {

                   System.out.println("Starting test method");

                   System.setProperty("webdriver.gecko.driver", "C:\\Users\\ramesh\\Desktop\\java\\desk\\geckodriver-v0.11.1-win64\\geckodriver.exe");

WebDriver driver=new FirefoxDriver();

driver.manage().window().maximize();

driver.manage().timeouts().implicitlyWait(50,TimeUnit.SECONDS);

driver.get("https://www.gmail.com");

          }

         

}

2.Write Listener in Listeners.java file and our class must implement ITestListener interface and add the unimplemented methods of that interface

package com.rameshsoft.rameshselenium;

import org.testng.ITestContext;

import org.testng.ITestListener;

import org.testng.ITestResult;

public class Listeners implements ITestListener {

          @Override

          public void onTestStart(ITestResult result) {

                   System.out.println("Test method started: "+result.getName());

          }

          @Override

          public void onTestSuccess(ITestResult result) {

                   System.out.println("Test method passed: "+result.getName());

                  

          }

          @Override

          public void onTestFailure(ITestResult result) {

                   System.out.println("Test method failed: "+result.getName());

                   }

          @Override

          public void onTestSkipped(ITestResult result) {

                   // TODO Auto-generated method stub

                  

          }

          @Override

          public void onTestFailedButWithinSuccessPercentage(ITestResult result) {

                   // TODO Auto-generated method stub

                  

          }

          @Override

          public void onStart(ITestContext context) {

                   System.out.println("hi...start");

                   // TODO Auto-generated method stub

                  

          }

          @Override

          public void onFinish(ITestContext context) {

                   // TODO Auto-generated method stub

                  

          }

}

OUTPUT:

[TestNG] Running:

 

Hi...start

Test method started: method

Starting test method

Test method passed: method

Configuring Listeners at suite level:

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE suite SYSTEM "http://testng.org/testng-1.0.dtd">

<suite name="Suite">

    <listeners>

        <listener class-name="com.rameshsoft.rameshselenium.Listeners"></listener>

    </listeners>

  <test name="Test">

    <classes>

      <class name="com.rameshsoft.rameshselenium.ListenerClassDemo"/>

    </classes>

  </test> <!-- Test -->

</suite> <!-- Suite -->