I have a Junit test class with two tests in it. test 1 will add an element to an ArrayList and passes it to the main class to do some logic and returns true. Test two should use the same arrayList and calls the same main class do the same logic but by the time the list comes to second test methods, its getting null.
I declared it as class variable. My questions is.. when I assign values to a class variable in a test method, will I not have access to the values in next test method? If yes, how should i retain the values.
Thanks,
Mahi
The way variables work in jUnit is that they get initialized before each test. So if you added value x to a list in Test1, it won't be there when you run Test2. If you want to some kind of initialization before each test, use the setup method.
Related
Well, I'm doing simple test to understand junit and to be honest I don't understand why
#Test
void findById() {
Long id= 2L;
Visit returnedVisit = service.findById(id);
assertEquals(Long.valueOf(4L),id);
}
id is equal 2 after changing value in tested method
public Visit findById(Long aLong) {
aLong= 4L;
return new Visit();
}
This is because the local primitive variable id in one method (your test case) is set to 2. It is then passed by value to the other method. Passing by value means to put an exact bit-wise copy on the call stack. That called method sets its local copy of the variable, but that does not modify the caller's variable.
If you passed a list, you would see modifications, because the list reference is passed by value, and you can make changes to the list like adding new elements, and the caller's list is modified. You can also modify the reference to the list, but the caller won't see it, i.e., if you reassign the list to some new list in the called method, the caller will still have the old list.
This is just how Java passes parameters; it has nothing to do with JUnit.
See also this question and its answers.
Student here. In JUnit 5, what is the best way to invoke a #Nested test class multiple times, but with slightly different state each time?
I see that JUnit 5 has an (experimental) #ParameterizedTest feature that is based on the (non-experimental) #TestTemplate feature, but both of those apply to test methods only, rather than nested test classes.
I have a heavy #Nested test class that needs to be invoked once for each value of an enum (preferably with a distinct #Tag value for each invocation), and I would prefer to avoid the "copy-and-paste" method of parameterization.
It is not currently possible to execute a test class multiple times in JUnit Jupiter.
To participate in the discussion, see the following issue: https://github.com/junit-team/junit5/issues/878
I want non-static method of an object returned by a static factory method to return a specific result.
After I have done this setup my test code will be calling the ConnectionFactory.getConn("ABC") indirectly through another piece of code which is being tested.
PowerMockito.when(ConnectionFactory.getConn("ABC").getCurrentStatus()).thenReturn(ConnectionStatus.CONNECTED);
I get a NPE for the above statement.
I already have #PrepareForTest({FXAllConnectionFactory.class, ConnectionStatus.class}) at the beginning of my junit test class.
What would be the correct way of doing it?
Thanks in advance :)
I guess there is no point in creating a fluent/chained call for your test setup.
You see:
PowerMockito.when(ConnectionFactory.getConn("ABC").getCurrentStatus()).thenReturn(ConnectionStatus.CONNECTED);
is probably meant to configure two calls:
ConnectionFactory.getConn("ABC") and then
getCurrentStatus() on the result of that first call
And what makes you think that PowerMockito magically knows what should be returned by that first call to getConn()?
In other words:
First provide a mocked Connection object X; and configure your mocks so that getConn() returns that object
In addition to that, you have to configure X to return the desired value upon a call to getCurrentStatus() ... on X!
So, the answer is actually: what you want to do isn't possible. The idea is; you specify behavior such as:
when A.foo() is called; then return some X
There is no magic power within PowerMockito to turn
when A.foo().bar() is called thren return Y
into
when A.foo() is called, return X; when X.bar() is called return Y
You have to specify that step by step.
List<Populate> fullAttrPopulateList = getFullAtrributesPopulateList(); //Prepare return list
when(mockEmployeeDao.getPopulateList(null)).thenReturn(fullAttrPopulateList);
MyDTO myDto = testablePopService.getMyPopData(); //Will call mockEmployeeDao.getPopulateList(null)
//verify(mockEmployeeDao,times(1)).getPopulateList(null);
assertEquals(fullAttrPopulateList.size(), myDto.getPopData().size()); //This fails because myDto.getPopData().size() returns 0
As you can see testablePopService.getMyPopData() calls mockEmployeeDao.getPopulateList(null) but when I debug it a zero sized list returns instead of the stubbed array list which is prepared by getFullAtrributesPopulateList();
If I uncomment the verify statement, it passes the test meaning getPopulateList(null) behavior does get called.
Can anyone give me some advice why my stubbed array list cannot be returned even it is verified the expected behavior happened? How come an empty array list returns rather than a null if I did something wrong?
First, check that the method is non-final and visible throughout its hierarchy. Mockito can have trouble mocking methods that are hidden (e.g. overriding a package-private abstract class's implementation); also, Mockito is entirely unable to mock final methods, or even to detect that the method is final and warn you about it.
You may also want to check that your call is using the overload you expect. Mockito's default list return value is an empty list, so you may simply stubbing one method and seeing the default value for another. You can see which method interactions Mockito has added by adding a call to verifyZeroInteractions temporarily, and Mockito will throw an exception with a list of calls that mock has received. You could also add verifyNoMoreInteractions, and even leave it in there, at the expense of test brittleness (i.e. the test breaks when the actual code continues to work).
I'm new to Junit. I want to write test cases for if condition,loops.
Do we have any guidelines or procedure to write test cases for if,loop conditions?
Can anyone explain with an example?
IF Age < 18 THEN WHILE Age <> 18
DO ResultResult = Result +1 AgeAge = Age +1 END
DO Print “You can start driving in {Result} years”
ELSE
Print “You can start driving now!”
ENDIF
You want one test case for each major scenario that your code is supposed to be able to handle. With an "if" statement, there are generally two cases, although you might include a third case which is the "boundary" of the two. With a loop, you might want to include a case where the loop is run multiple times, and also a case where the loop is not run at all.
In your particular example, I would write three test cases - one where the age is less than 18, one where the age is exactly 18, and one where the age is over 18. In JUnit, each test case is a separate method inside a test class. Each test method should run the code that you're testing, in the particular scenario, then assert that the result was correct.
Lastly, you need to consider what to call each test method. I strongly recommend using a sentence that indicates which scenario you're testing, and what you expect to happen. Some people like to begin their test method names with the word "test"; but my experience is that this tends to draw attention away from what CONDITION you're trying to test, and draws attention toward which particular method or function it is that you're testing, and you tend to get lower quality tests as a result. For your example, I would call the test methods something like this.
public void canStartDrivingIfAgeOver18()
public void canStartDrivingIfAgeEquals18()
public void numberOfYearsRemainingIsShownIfAgeUnder18()
From my understanding of writing in junit for java ,we were used to create a source code into different blocks is the code conventional,and used to pass the values as args to the function from the test cases so the values will steps into the block statements ,and passes the test cases .
For example you are having the variable as age by assuming as functionName(int age), for testing you should pass the integer from the test case as functionName(18) it will steps into the statements and will show you the status of the test case.Create test case for a testing class write test case for the functions
UseClass classObj=new UseClass();// it should be your class
#Test
public void testValidateAge() {
classObj.validateAge("20");
assertEquals(200,"");
}
Correct me if 'm wrong :)