JUnit basic usage

Some JUnit Notes:

• Test methods must be modified to use @Test
• Public void test method must be modified, not arguments
• Unit tests are generally used to create a new test directory for testing code, just to test the code directory can be deleted at the time of production deployment
• Test code and the package should be consistent test code packet structure
• Each test unit independent method must be tested, there can be no dependencies between methods
• Test test class is generally used as the class name suffix
• The test method is generally used as a test method name prefix

Test failed Explanation:

• Failure: generally due to inconsistent test results and expected results triggered, indicating that the point of the test found a problem
• error: abnormal is caused by the code, it can generate an error in the test code itself, may be hidden in the test code bug

Some common notes:

• @Test: One common method is modified to a testing method
  • @Test (excepted = xx.class): indicates when xx.class exception classes, representation of the test This exception is thrown, the test is considered normal by
  • @Test (timeout = milliseconds): test method execution time is in line with expectations
• @BeforeClass: will be executed before the execution of all methods, static methods (globally only once, and was the first run)
• @AfterClass: will be executed, static method (globally only once, and the last run) after all of the execution method
• @Before: will be executed once before each test method is run
• @After: will be performed once after each test method run
• @Ignore: The modified test method will be ignored test runner
• @RunWith: You can change the test runner org.junit.runner.Runner
• Parameters: Parameter annotation

Parametric tests:

For a method requires numerous test scenarios, the workload may be reduced by testing parameterized test. Usage is as follows:

Package junit.util. 1; 
 2 
 . 3 Import static org.junit.Assert.assertEquals; 
 . 4 
 . 5 Import java.util.Arrays; 
 . 6 Import java.util.Collection; 
 . 7 
 . 8 Import org.junit.Test; 
 . 9 Import the org.junit. runner.RunWith; 
10 Import org.junit.runners.Parameterized; 
. 11 Import org.junit.runners.Parameterized.Parameters; 
12 is 
13 is @RunWith (Parameterized.class) 
14 {public class ParameterTest 
15 
16 / ** 
. 17 *. 1, change test runner is RunWith (Parameterized.class) 
18 is 2 *, declare a variable used to store the expected value and the result value 
19 * 3, a declared value Collection of public static method returns, and using modified @Parameters 
20 * 4 bit public constructor with a class declaration test parameter, and in which a variable assignment statement is 
21 * /
22 is      
23 is the except int; // to store the expected result 
24 int input1; // for storing a first input parameter 
25 int input2; // for storing the second input parameter 
26 is      
27 @Parameters 
28 public static Collection <Object []> initTestData () { 
29 return Arrays.asList ( 
30 new new Object [] [] { 
31 is {3,1,2}, 
32 {10,5,5}, 
33 is} {6, 4, 
34 is { }} 7,3,4 
35); 
36} 
37 [      
38 is public ParameterTest (the except int, int INPUT1, INPUT2 int) { 
39 = the except this.except; 
40 this.input1 = INPUT1; 
41 is this.input2 = INPUT2; 
42 is} 
43      
44      
45      
46 is      
47     
48     @Test
49     public void testAdd() {
50     assertEquals(except, new Claculate().add(input1, input2));
51     }
52 
53 }