Android Tutorial => Creating Local unit tests

Example

Place your test classes here: /src/test/<pkg_name>/

Example test class

public class ExampleUnitTest {
    @Test
    public void addition_isCorrect() throws Exception {
        int a=4, b=5, c;
        c = a + b;
        assertEquals(9, c); // This test passes
        assertEquals(10, c); //Test fails
    }
}

Breakdown

public class ExampleUnitTest {
  ...
}

The test class, you can create several test classes and place them inside the test package.

@Test
public void addition_isCorrect() {
   ...
}

The test method, several test methods can be created inside a test class.

Notice the annotation @Test.

The Test annotation tells JUnit that the public void method to which it is attached can be run as a test case.

There are several other useful annotations like @Before, @After etc. This page would be a good place to start.

assertEquals(9, c); // This test passes
assertEquals(10, c); //Test fails

These methods are member of the Assert class. Some other useful methods are assertFalse(), assertNotNull(), assertTrue etc. Here's an elaborate Explanation.

Annotation Information for JUnit Test:

@Test: The Test annotation tells JUnit that the public void method to which it is attached can be run as a test case. To run the method, JUnit first constructs a fresh instance of the class then invokes the annotated method.

@Before: When writing tests, it is common to find that several tests need similar objects created before they can run. Annotating a public void method with @Before causes that method to be run before the Test method.

@After: If you allocate external resources in a Before method you need to release them after the test runs. Annotating a public void method with @After causes that method to be run after the Test method. All @After methods are guaranteed to run even if a Before or Test method throws an exception

Tip Quickly create test classes in Android Studio

Place the cursor on the class name for which you want to create a test class.
Press Alt + Enter (Windows).
Select Create Test, hit Return.
Select the methods for which you want to create test methods, click OK.
Select the directory where you want to create the test class.
You're done, this what you get is your first test.

Tip Easily execute tests in Android Studio

Right click test the package.
Select Run 'Tests in ...
All the tests in the package will be executed at once.

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Fastest Entity Framework Extensions

Example

Example test class

Breakdown

Tip Quickly create test classes in Android Studio

Tip Easily execute tests in Android Studio

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Android

Android Unit testing in Android with JUnit Creating Local unit tests

Fastest Entity Framework Extensions

Example

Example test class

Breakdown

Tip Quickly create test classes in Android Studio

Tip Easily execute tests in Android Studio

Got any Android Question?