java - What are JUnit @Before and @Test

Question

What is the use of a Junit @Before and @Test annotations in java? How can I use them with netbeans?

Answer 1

Can you be more precise? Do you need to understand what are @Before and @Test annotation?

@Test annotation is an annotation (since JUnit 4) that indicates the attached method is an unit test. That allows you to use any method name to have a test. For example:

@Test
public void doSomeTestOnAMethod() {
  // Your test goes here.
  ...
}

The @Before annotation indicates that the attached method will be run before any test in the class. It is mainly used to setup some objects needed by your tests:

(edited to add imports) :

import static org.junit.Assert.*; // Allows you to use directly assert methods, such as assertTrue(...), assertNull(...)

import org.junit.Test; // for @Test
import org.junit.Before; // for @Before

public class MyTest {

    private AnyObject anyObject;

    @Before
    public void initObjects() {
        anyObject = new AnyObject();
    }

    @Test
    public void aTestUsingAnyObject() {
        // Here, anyObject is not null...
        assertNotNull(anyObject);
        ...
    }

}

Answer 2

1. If I understood you correctly, you want to know, what the annotation @Before means. The annotation marks a method as to be executed before each test will be executed. There you can implement the old setup() procedure.

2. The @Test annotation marks the following method as a JUnit test. The testrunner will identify every method annotated with @Test and executes it. Example:

   import org.junit.*;
   
   public class IntroductionTests {
       @Test
       public void testSum() {
         Assert.assertEquals(8, 6 + 2);
       }
   }
   

3. How can i use it with Netbeans? In Netbeans, a testrunner for JUnit tests is included. You can choose it in your Execute Dialog.