[Go] Use JUNIT4 for unit testing in Eclipse (beginner)

First, let's take a stupid crash tutorial and don't ask why, follow Me, let's experience the thrill of unit testing!

First create a new project called Junit_test, we write a calculator class, this is a simple implementation of the subtraction, square, the root of the calculator class, and then to unit test these functions. This class is not perfect, and we deliberately keep some bugs for demonstration, which are described in the comments. This type of code is as follows:

Package Andycpp;public class Calculator {    private static int result;    Static variable for storing the run result public    void Add (int n)    {        result=result+n;    }        public void substract (int n)    {        result=result-1;        Bug: The correct one should be result=result-n;    }        public void Multiply (int n)    {        //This method has not been written well    } public        void divide (int n)    {        result=result/n;    }        public void Square (int n)    {        result=n*n;    }        public void SquareRoot (int n)    {for        (;;);    Bug: Dead Loop    } public        void Clear ()    {        result=0;  Clear the result 0    } public        int getresult ()    {        return result;}    }

The second step is to introduce the JUNIT4 Unit test package into this project: Right-click on the item, click "Properties",

In the pop-up Properties window, first select "Java Build Path" on the left, then select "Libraries" tab on the right, then click "Add Library ..." button on the far right, as shown in

Then select JUnit4 in the new pop-up dialog and click OK, as shown in the JUNIT4 software package is included in our project.

The third step is to generate the JUnit test framework: In Eclipse's Package Explorer, right-click on the pop-up menu and select "New-junit test Case". As shown in the following:

In the popup dialog box, make the appropriate selections as shown in:

After clicking "Next", the system will automatically list the methods contained in your class and choose the method you want to test. In this example, we only test the "add, subtract, multiply, divide" four methods. As shown in the following:

The system then automatically generates a new class calculatortest, which contains some empty test cases. You only need to make these test cases slightly modified to use.

The complete calculatortest code is as follows:

Package Andycpp;import static Org.junit.assert.*;import Org.junit.after;import Org.junit.before;import Org.junit.ignore;import Org.junit.test;import Org.junit.internal.runners.testclassrunner;import Org.junit.runner.RunWith; @RunWith (testclassrunner.class) public class Calculatortest {private static Calculator        Calculator=new calculator ();    @Before public void SetUp () throws Exception {calculator.clear (); } @After public void TearDown () throws Exception {} @Test (timeout=1000) public void Testadd () {cal        Culator.add (2);        Calculator.add (3);    Assertequals (5, Calculator.getresult ());        } @Test public void Testsubstract () {calculator.add (10);        Calculator.substract (2);    Assertequals (8,calculator.getresult ()); The @Ignore ("Multiply () Not yet implemented") @Test the public void Testmultiply () {} @Test (expected = arithmeticexception.class) public void Testdivide () {Calculator.add (8);        Calculator.divide (0);    Assertequals (4,calculator.getresult ()); }}

Fourth step, run the test code: After modifying the code as described above, we right-click on the Calculatortest class and select "Run As-junit Test" to run our test as shown in:

The results of the operation are as follows:

Progress bar is red color indicates found error, the specific test results on the progress bar indicates "a total of 4 tests, of which 1 tests were ignored, one test failed."

At this point, we have fully experienced the methods of using JUnit in Eclipse.

[Go] Use JUNIT4 for unit testing in Eclipse (beginner)