JUnit设置测试用例

Question

I have never used JUnit before and I'm having some trouble setting up the tests. I have a Java project and a package, both named 'Project1' with one class which I'm trying to test called 'Module'. At the moment I'm just wanting to check if the values are correct.

Module class

package Project1;
//This class represents a module
public class Module {

      public final static int MSC_MODULE_PASS_MARK = 50;
      public final static int UG_MODULE_PASS_MARK = 40;
      public final static int MSC_MODULE_LEVEL = 7;
      public final static int STAGE_3_MODULE_LEVEL = 6;

      private String moduleCode;
      private String moduleTitle;
      private int sem1Credits;
      private int sem2Credits;
      private  int sem3Credits;
      private  int moduleLevel;


      public Module(String code, String title, int sem1, int sem2, int sem3, int level)
      {

          moduleCode = code;
          moduleTitle = title;
          sem1Credits = sem1;
          sem2Credits = sem2;
          sem3Credits = sem3;
          moduleLevel = level;

      }

      //method to return the module code
      public String getCode()
      {

          return moduleCode;

      }
      //INSERT A BUNCH OF GET METHODS

}

Test case

Here is where I get lost. I'm trying to give some dummy values to test but I'm not sure how to pass the instance of Module to test.

package Project1;

import static org.junit.Assert.*;

import org.junit.Before;
import org.junit.BeforeClass;
import org.junit.Test;


public class TestCase {
    @BeforeClass
    public static void setUpBeforeClass() throws Exception {


    }

    @Before
    public void setUp() throws Exception {
        Module csc8001 = new Module("CSC8001", "Programming and data structures", 20, 0, 0, 7);

    }
    @Test
    public void test() {
        if (csc8001.getCode() == "CSC8001") {
            System.out.println("Correct");
        }
        else{
            fail("Not yet implemented");
        }
    }

}

Answer 1

Make your Module variable an instance variable in your test class, instead of a local variable in a method. Then the @Before method will just initialize the variable, not declare it too. Then it will be in scope in any @Test method.

Incidentally, compare your string contents with String 's equals method, not == .

Answer 2

Always use equals:

if (csc8001.getCode().equals("CSC8001")) {

furthermore declare csc8001 as a class member.

public class TestCase {
private Module csc8001;

and

@Before
    public void setUp() throws Exception {
        csc8001 = new Module("CSC8001", "Programming and data structures", 20, 0, 0, 7);

    }

Answer 3

Make your Module an instance variable. Remember that for each separate @Test method, JUnit will create a separate instance of your test class and run all of your @Before methods on it. Though you can instantiate your system under test in the same place you declare it, it may be advantageous to keep it in @Before as you have it .

public class TestCase {
  private Module csc8001;

  @Before public void setUp() throws Exception {
    csc8001 = new Module("CSC8001", "Programming and data structures", 20, 0, 0, 7);
  }

  @Test public void test() { /* ... */ }
}

You can also use assertEquals to check equality, which will automatically fail with a clear message if the parameters don't match.

@Test
public void codeShouldEqualCSC8001() {
  assertEquals("CSC8001", csc8001.getCode());
}

See assertEquals and more at the org.junit.Assert documentation .

ps Remember that the prefix test and the name setUp are holdovers from JUnit 3, and that using JUnit4 or better (with annotations like @Before and @Test ) you are free to add multiple @Before and @After methods and give all your methods unconstrained names.

Answer 4

import static org.junit.Assert.assertEquals;

public class TestCase {

   private final Module csc8001 = new Module("CSC8001", "Programming and data structures", 20, 0, 0, 7);


    @Test
    public void testGetCode() {
        assertEquals("Some error message", "CSC8001", csc8001.getCode()) ;
    }

}