JUnit - Parallel Testing

Running your tests in parallel is a powerful way to speed up your tests.
Good automated tests should be independent, isolated and reproducible, making them ideal candidates for being run concurrently
But in real world scenarios of web testing this hardly happens and when it does we must make use of JUnit parallel testing capability to speed up the testing

Example

@Test
public void Test1() {
System.out.println("In Test 1");
}

@Test
public void Test2() {
System.out.println("In Test 2");
}

@Test
public void Test3() {
System.out.println("In Test 3");
}

Runner class

@RunWith(ParallelSuite.class)
@SuiteClasses({Test1.class, Test2.class, Test3.class})
public class ABCSuite {}

Dependencies 

<dependency>
    <groupId>com.googlecode.junit-toolbox</groupId>
    <artifactId>junit-toolbox</artifactId>
    <version>2.0</version>
</dependency>

JUnit - Download and Install

Download the following jars file from http://search.maven.org/

junit.jar
hamcrest-core.jar

Maven Dependencies

JUnit

<dependency>
  <groupId>junit</groupId>
  <artifactId>junit</artifactId>
  <version>4.11</version>
  <scope>test</scope>
</dependency>

Hamcrest

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.hamcrest</groupId>
<artifactId>hamcrest-parent</artifactId>
<version>1.3</version>
</parent>
<artifactId>hamcrest-core</artifactId>
<packaging>jar</packaging>
<name>Hamcrest Core</name>
<description>
This is the core API of hamcrest matcher framework to be used by third-party framework providers. This includes the a foundation set of matcher implementations for common operations.
</description>
</project>

JUnit Exception Testing

In Automation, it is not only important to check if screens behave as expected with correct data, it is also important to check if tests would throw exception when invalid/inappropriate data is given, this will make the Framework more robust

Lets see how JUnit allows us to do Excepton Testing

Example 1

new ArrayList<Object>().get(0); // Array list is empty, so it should result in IndexOutOfBoundsException

  @Test(expected= IndexOutOfBoundsException.class)
    public void empty() {
         new ArrayList<Object>().get(0);
    }
So this test case would pass, if IndexOutOfBoundsException is thrown else the Test case fails

Example 2

 @Test
    public void testExceptionMessage() {
        try {
            new ArrayList<Object>().get(0);
            fail("Expected an IndexOutOfBoundsException to be thrown");
}

         catch (IndexOutOfBoundsException anIndexOutOfBoundsException) {
            assertThat(anIndexOutOfBoundsException.getMessage(), is("Index: 0, Size: 0"));
            }
    }

In this way we can not only test what Exception we get but we can also validate what message is thrown 

JUnit Assertions

Assertions is one of the most used and important part of your Framework
JUnit provides overloaded Assertions for all primitive types(ie int, string etc), Objects and Arrays(Primitive and Objects)

Syntax for Assertions
<expected_value> , <actual_value>
or
<String output for failure>, <expected_value> , <actual_value>

Examples

1)Compares if text are same
 @Test
  public void testAssertEquals() {
    org.junit.Assert.assertEquals("failure - strings are not equal", "text", "text");
  }

2)Checks if condition passed results in false, if false_var is evaluated to true then error is shown
Remember this condition can be used to optionally run your test case, if you include this in your @Before Class

  @Test
  public void testAssertFalse() {
    org.junit.Assert.assertFalse("failure - should be false", false_var);
  }

3)Checks if the obect passed is null or not, if not null, then shows error
   @Test
  public void testAssertNotNull() {
    org.junit.Assert.assertNotNull("should not be null", new Object());
  }

4)Checks if two obects are same
  @Test
  public void testAssertNotSame() {
    org.junit.Assert.assertNotSame("should not be same Object", new Object(), new Object());
  }

A slightly different assertion is assertThat, usage is

Syntax
<optional_failure_msg> , <actual_value> , <matcher_Object>

asserThat is used in the suitations, where the actual value is dynamically generated and you can use a matcher obect to verify it at run time with a pattern

Examples

1) This can be used to check your order_num pattern, date etc
 @Test
  public void testAssertThatBothContainsString() {
    org.junit.Assert.assertThat("albumen", both(containsString("a")).and(containsString("b")));
  }

2)Checks the Array List

  @Test
  public void testAssertThatEveryItemContainsString() {
    org.junit.Assert.assertThat(Arrays.asList(new String[] { "fun", "ban", "net" }), everyItem(containsString("n")));
  }