JUnit - API

JUnit - API

Important APIs in JUnit

The most important package in JUnit is junit.framework contains all the core classes. Some important classes are listed below:

Serial number	The name of the class	The functionality of the class
1	Assert	assert of assert methods
2	TestCase	A fixture that defines how to run multiple tests
3	TestResult	TestResult all the results of performing a test sample
4	TestSuite	TestSuite a collection of tests

Assert class

Here's org.junit.Assert class:

public class Assert extends java.lang.Object

This class provides a series of useful declaration methods for writing tests. O nly failed claims methods are logged. Assert method columns for the Assert class are as follows:

Serial number	Method and description
1	​ ​void assertEquals​(boolean expected, boolean actual) ​ Check that the two variables or the equals are balanced
2	​ ​void assertFalse​(boolean condition) ​ The check conditions are false
3	​ ​ void assertNotNull ​(Object object) ​ The check object is not empty
4	​ ​ void assertNull ​(Object object) ​ The check object is empty
5	​ ​ void assertTrue ​(boolean condition) ​ The check condition is true
6	​ ​ void fail ​() ​ Make the test fail without reporting

Let's test some of the methods mentioned above in the example. I n C: Create a JUNIT_WORKSPACE called TestJunit1.java in the .java directory.

import org.junit.Test;
import static org.junit.Assert.*;
public class TestJunit1 {
   @Test
   public void testAdd() {
      //test data
      int num= 5;
      String temp= null;
      String str= "Junit is working fine";

      //check for equality
      assertEquals("Junit is working fine", str);

      //check for false condition
      assertFalse(num > 6);

      //check for not null value
      assertNotNull(str);
   }
}

Next, we'll be at C: The test case JUNIT_WORKSPACE a class named TestRunner1.java in the .java the testrunner directory to execute.

import org.junit.runner.JUnitCore;
import org.junit.runner.Result;
import org.junit.runner.notification.Failure;

public class TestRunner1 {
   public static void main(String[] args) {
      Result result = JUnitCore.runClasses(TestJunit1.class);
      for (Failure failure : result.getFailures()) {
         System.out.println(failure.toString());
      }
      System.out.println(result.wasSuccessful());
   }
}   

The Test case and Test case are Test Runner

C:\JUNIT_WORKSPACE>javac TestJunit1.java TestRunner1.java

Now run Test Runner it will run the test Test Case defined and provided in the Test Case class.

C:\JUNIT_WORKSPACE>java TestRunner1

Check the output.

true

TestCase class

Here's org.junit.TestCaset class:

public abstract class TestCase extends Assert implements Test

The test sample defines a fixed format for running multiple tests. Some of the important methods of the TestCase class are listed as follows:

Serial number	Method and description
1	​ int countTestCases() ​ Count of test cases executed for run (TestResult result).
2	​ TestResult createResult() ​ Create a default TestResult object
3	​ String getName() ​ Gets the name of TestCase
4	​ TestResult run() ​ A convenient way to run this test and collect the results produced by the TestResult object
5	​ void run(TestResult result) ​ Run the test case in TestResult and collect the results
6	​ void setName(String name) ​ Set the name of TestCase
7	​ void setUp() ​ Create a fixture, for example, to turn on a network connection
8	​ void tearDown() ​ Remove the fixture, for example, to turn off a network connection
9	​ String toString() ​ Returns a string representing the test case

Let's try the method mentioned above in the example. I n C: Create a JUNIT_WORKSPACE called TestJunit2.java under the .java path.

import junit.framework.TestCase;
import org.junit.Before;
import org.junit.Test;
public class TestJunit2 extends TestCase  {
   protected double fValue1;
   protected double fValue2;

   @Before 
   public void setUp() {
      fValue1= 2.0;
      fValue2= 3.0;
   }

   @Test
   public void testAdd() {
      //count the number of test cases
      System.out.println("No of Test Case = "+ this.countTestCases());

      //test getName 
      String name= this.getName();
      System.out.println("Test Case Name = "+ name);

      //test setName
      this.setName("testNewAdd");
      String newName= this.getName();
      System.out.println("Updated Test Case Name = "+ newName);
   }
   //tearDown used to close the connection or clean up activities
   public void tearDown(  ) {
   }
}

Next, in C: The test case JUNIT_WORKSPACE a class called TestRunner2.java .java under the path to execute the test case.

import org.junit.runner.JUnitCore;
import org.junit.runner.Result;
import org.junit.runner.notification.Failure;

public class TestRunner2 {
   public static void main(String[] args) {
      Result result = JUnitCore.runClasses(TestJunit2.class);
      for (Failure failure : result.getFailures()) {
         System.out.println(failure.toString());
      }
      System.out.println(result.wasSuccessful());
   }
}

The Test case and Test case are Test Runner

C:\JUNIT_WORKSPACE>javac TestJunit2.java TestRunner2.java

Now run Test Runner it will run the test Test Case defined and provided in the Test Case class.

C:\JUNIT_WORKSPACE>java TestRunner2

Check the output.

No of Test Case = 1
Test Case Name = testAdd
Updated Test Case Name = testNewAdd
true

TestResult class

The following is org.junit.TestResult class:

public class TestResult extends Object

TestResult the results of all execution test cases. I t is an example of the collection parameter plane. T his experimental framework distinguishes between failure and error. F ailures are predictable and can be checked by assumptions. E rrors are unpredictable problems ArrayIndexOutOfBoundsException Some of the important methods of the TestResult class are listed as follows:

Serial number	Method and description
1	​ ​ void addError ​​ (Test test, Throwable t) ​ ​ Add an error to the error list
2	​ ​ void addFailure ​(Test test, AssertionFailedError t) ​ Add a failure to the list of failures
3	​​ void endTest ​(Test test) ​ Displays the results of the test being compiled
4	​ int errorCount() ​ Gets the number of errors detected
5	​ Enumeration errors() ​ Returns the details of the error
6	​ int failureCount() ​ Gets the number of failures detected
7	void run(TestCase test runs TestCase
8	​ int runCount() ​ Gets the number of tests to run
9	​ void startTest(Test test) ​ Declare that a test is about to begin
10	​ void stop() ​ Indicates that the test must be stopped

In C: Create a JUNIT_WORKSPACE called TestJunit3.java under the .java path.

import org.junit.Test;
import junit.framework.AssertionFailedError;
import junit.framework.TestResult;

public class TestJunit3 extends TestResult {
   // add the error
   public synchronized void addError(Test test, Throwable t) {
      super.addError((junit.framework.Test) test, t);
   }

   // add the failure
   public synchronized void addFailure(Test test, AssertionFailedError t) {
      super.addFailure((junit.framework.Test) test, t);
   }
   @Test
   public void testAdd() {
   // add any test
   }

   // Marks that the test run should stop.
   public synchronized void stop() {
   //stop the test here
   }
}

Next, in C: The test case JUNIT_WORKSPACE a class called TestRunner3.java under the path to execute the test case.

import org.junit.runner.JUnitCore;
import org.junit.runner.Result;
import org.junit.runner.notification.Failure;

public class TestRunner3 {
   public static void main(String[] args) {
      Result result = JUnitCore.runClasses(TestJunit3.class);
      for (Failure failure : result.getFailures()) {
         System.out.println(failure.toString());
      }
      System.out.println(result.wasSuccessful());
   }
}   

The Test case and Test case are Test Runner

C:\JUNIT_WORKSPACE>javac TestJunit3.java TestRunner3.java

Now run Test Runner it will run the test Test Case defined and provided in the Test Case class.

C:\JUNIT_WORKSPACE>java TestRunner3

Check the output.

true

TestSuite class

The following is org.junit.TestSuite class:

public class TestSuite extends Object implements Test

TestSuite class is part of the test. I t runs a lot of test cases. Some important method columns for the TestSuite class are as follows:

Serial number	Method and description
1	​ void addTest(Test test) ​ Add a test to the set.
2	​ void addTestSuite(Class<? extends TestCase> testClass) ​ Add tests from a class that has already been given to the set.
3	​ int countTestCases() ​ Count the test cases that the test is about to run.
4	​ String getName() ​ Returns the name of the set.
5	​ void run(TestResult result) ​ Run tests and collect results in TestResult.
6	​ void setName(String name) ​ The name of the set.
7	​ Test testAt(int index) ​ The test is returned in the given directory.
8	​ int testCount() ​ Returns the number of tests in the set.
9	​ static Test warning(String message) ​ Returns a test that will fail and logs a warning message.

In C: Create a JUNIT_WORKSPACE called JunitTestSuite.java under the .java path.

import junit.framework.*;
public class JunitTestSuite {
   public static void main(String[] a) {
      // add the test's in the suite
      TestSuite suite = new TestSuite(TestJunit1.class, TestJunit2.class, TestJunit3.class );
      TestResult result = new TestResult();
      suite.run(result);
      System.out.println("Number of test cases = " + result.runCount());
    }
}

Compile Test Test suit

C:\JUNIT_WORKSPACE>javac JunitTestSuite.java

Now run Test Suit

C:\JUNIT_WORKSPACE>java JunitTestSuite

Check the output.

No of Test Case = 1
Test Case Name = testAdd
Updated Test Case Name = testNewAdd
Number of test cases = 3