How to add test suite dynamically in junit 4.10 - junit

I wanted to know if there's any way to add test suites dynamically in junit 4.
For example I have a TestClassA as mentioned below having test case "test1"
class TestClassA
{
#Test
public void test1()
{
createTestClassDynamically(); // this creates a test class having
// setUp(), tearDown() methods and one test case .
}
}
Test case test1 has a method createTestClassDynamically() that dynamically creates a new test class (lets say TestClassB) having setUp(), tearDown() methods and one test case (lets say test2()).
I want to run the test1 and then when TestClassB is dynamically generated I want test case "test2" also to be executed.
I know this is quite complicated and not the best thing to do but in my framework I need to do it to generate large number of test classes dynamically rather than having them physically in the package.
Can anyone please provide any help/suggestions?

I have solved this is my framework using the Parameterized feature of Junit 4 which helps to execute same test case with different parameters.
Below mentioned is the sample code on how I acheived it, thought to post it if it helps anyone.
Also, if someone has a better solution, feel free to post it.
class TestClassA
{
private TestClassB classBObj;
public TestClassA(TestClassB obj) {
classBObj= obj;
}
#Test
public void test1()
{
// createTestClassDynamically(); // remove this method as Parameterized
// feature will take care of dynamic test execution.
}
#Test
public void test2()
{
// Test case from Test class B using TestClassB object (classBObj)
}
public static Collection<Object[]> getParameters() {
Collection<Object[]> parameteres = new ArrayList<Object[]>();
Object[] obj1 = new Object[]{new TestClassB()};
Object[] obj2 = new Object[]{new TestClassB()};
parameteres.add(obj1);
parameteres.add(obj2);
// ....... add more test data this way or create a loop
return parameteres;
}
}

Related

How To write test method for ResultSetExtractor using mockito?

How to write a method in myDAOTest class to test my DAOImpl Class using Mockito? here is the method which i need to test from my TestClass.
#Override
public myCustomResponse mymethod(String query, Map<String, Object> parameters) {
jdbcTemplate.query(query, parameters, new ResultSetExtractor<List<MyObject>>() {
#Override
public List<MyObject> extractData(ResultSet result) throws SQLException, DataAccessException {
try {
List<MyObject> myObject= new ArrayList<>();
while (result.next()) {
response = getResponseDetails(result);
}
return myObject;
} catch (SQLException sqlException) {
LOG.debug(MyConstants.DATABASE_EXCEPTION_MESSAGE);
throw new MyCustomeException(MyConstants.DATABASE_EXCEPTION_MESSAGE);
}
}
});
}
return response;
}
Possibility 1:
Extract your ResultSetExtractor into it's own class, which makes it much simpler to test than as an anonymous inner class.
Possibility 2:
Mock the jdbcTemplate, create an ArgumentCaptor, call the method and then do...
Mockito.verify(this.jdbcTemplate).query(any(), any(), captor.capture());
This allows you to then get the ResultSetExtractor from the ArgumentCaptor and run tests on that. But this makes your whole test complex, so I still suggest possibility 1.
Possibility 3:
Test the whole thing against an in-memory database,testing the ResultSetExtractor only indirectly. Since this seems to be Spring, there are easy ways to do so, but of course, your unit test will now include a whole SpringApplicationContext, a db, etc. - which makes it slower than a "pure" unit test with only mocks. Since it's something that fires queries to a db, you will need to run it against a db anyway some time, otherwise your tests will not really be complete (simulating it via mocks is good for the basics, but not the same thing).

Is it possible to name a test suite in JUnit 4?

In JUnit3, one would could name a test suite like this:
public static Test suite() {
TestSuite suite = new TestSuite("Some test collection");
suite.addTestSuite(TestX.class);
return suite;
}
Is there an equivalent way to do this in JUnit4?
Thanks.
EDIT
Thank you, I actually managed to get it working. My question was if there is a JUnit4 equivalent way of specifying the name/description of a test suite, like in JUnit3 with "Some test collection".
Some background:
I'm converting junit tests in legacy code to the version 4, and I don't want to lose any information if possible. I apologize, I should really have been more specific in the original question.
You can do this with the Suite runner #RunWith(Suite.class):
#RunWith(Suite.class)
#SuiteClasses({Test1.class, Test2.class, TestX.class})
public class MySuite {}
Where Test1, Test2, TestX contain your tests
ref. RunWith, Suite
update:
WRT changing the actual description of your suite, I don't think there's a way to do it out-of-the-box (if there is I haven't seen it yet). What you can do, is to define your own runner with a custom description [update2]:
#RunWith(DescribedSuiteRunner.class)
#SuiteClasses({Test1.class, Test2.class, TestX.class})
#SuiteDescription("Some test collection")
public class MySuite {}
public class DescribedSuiteRunner extends Suite {
// forward to Suite
public DescribedSuiteRunner(Class<?> klass, RunnerBuilder builder)
throws InitializationError {
super(klass, builder);
}
#Override
protected String getName() {
return getTestClass()
.getJavaClass()
.getAnnotation(SuiteDescription.class)
.value();
}
}
#Retention(RetentionPolicy.RUNTIME)
#Target(ElementType.TYPE)
public #interface SuiteDescription {
String value();
}
The default implementation of getName just returns the class being tested's name
Yes, In JUnit 3.x, the JUnit methods had to be specifically named. They needed to begin with the word test in order for JUnit to run that as a test case. Now you can just use the #Test annotation:
#Test
public void thisIsMyTest() {
// test goes here
}
Also in JUnit4 you can state if you want some tests to run before or after all the tests in this class are invoked:
#Before
public void init() throws Exception {
System.out.println("Initializing...");
}
#After
public void finish() throws Exception {
System.out.println("Finishing...");
}
Further comparisons between JUnit3 and JUnit4 here and here.
Edit: after blgt's comment, I see I might have misunderstood your intent.
You are probably looking for #RunWith(Suite.class) - When a class is annotated with #RunWith, JUnit will invoke the class in which is annotated so as to run the tests, instead of using the runner built into JUnit. Full example of usage is here, tl;dr below:
#RunWith(Suite.class)
#SuiteClasses({ FirstTest.class, SecondTest.class })
public class AllTests {
...
}

Instantiate a class once per parameter in JUnit

So I'm trying to run tests that will evaluate certain properties of different websites. The actual evaluation is being handled by a pay-per-call resource, so I want to minimize the number of times I generate the resource. Also, I need this to run in JUnit to fit into a larger automated test suite.
I've been doing this with parameterized tests so far, but I just learned that they instantiate a new instance for each test method.
Now I'm trying to figure out a way to have the resource created just once for each parameter that is being fed into the constructor of my testing class. #BeforeClass does it just once, and #Before does it once before each test.
All the help topics I've been able to find have dealt with creating expensive resources once for all tests, but in this case I need the resource to be recreated for each new set of parameters.
I've written some example code / output below to better show what I'm looking for:
#RunWith(Parameterized.class)
public class MyTestClass {
private static Resource expensiveToCreateResource;
public MyTestClass(String url) {
System.out.println("Constructing resource for " + url);
expensiveToCreateResource = new Resource(url); //This is getting created 4x, which is wrong
}
#Parameters
public static Collection<Object[]> data() {
return Arrays.asList(new Object[][] {{"url1"},{"url2"}});
}
#Test
public test1() {
expensiveToCreateResource.method1();
System.out.println("test1");
}
#Test
public test2() {
expensiveToCreateResource.method2();
System.out.println("test2");
}
}
would produce output:
Constructing resource for url1
test1
test2
Constructing resource for url2
test1
test2
Any ideas / solutions? Thanks.
If you want to have the class instantiated once per parameter, you'll have to write your own JUnit test runner. Instead I'd try to cache the information as needed, e.g. in a static map that maps URLs to resources.

Suppress JOptionPane.showInputDialog in junit test

I am using the JOptionPane.showInputDialog call in my code.
When the junit tests run it pops up the window.
Is there a way to suppress the pop-up?
Wold mocking it help?
Please help me on this.
I know - this question is ancient. But maybe sometimes someone will have the same problem...
Remember: It's your code, isn't it? So you can easily refactor from
public boolean myMethod() {
String value = "NOTHING";
if(this.someCondition) {
value = JOptionPane.showInputDialog(...);
}
return "NOTHING".equals(value);
}
to
public boolean myMethod() {
String value = "NOTHING";
if(this.someCondition) {
value = getValueFromDialog();
}
return "NOTHING".equals(value);
}
protected getValueFromDialog() {
return JOptionPane.showInputDialog(...)
}
This done, you can write a test mocking away the actual invocation of JOptionPane (Example uses Mockito syntax)
#Test
public void test_myMethod() {
MyClass toTest = mock(MyClass.class);
//Call real method we want to test
when(toTest.myMethod()).doCallRealMethod();
//Mock away JOptionPane
when(toTest.getValueFromDialog()).thenReturn("HELLO JUNIT");
//Perform actual test code
assertFalse(toTest.myMethod());
}
All done - now add tests simulating all the funny stuff that might happen as a result of JOptionPane.showInputDialog() (returning null, returning unexpected values...) by simply adding test cases and different values for
when(toTest.getValueFromDialog()).thenReturn(...);

Passing command line arguments to JUnit in Eclipse

All,
I am currently using JUnit 4 for writing test cases. I am fairly new to JUnit and finding it difficult to test my main class which takes arguments. I have specified the arguments to my JUnit test class by:
1 > Right click JUnit test class
2 > Goto Run As -> Run Configurations
3 > Select the Arguments tab and specify a value (I have entered an invalid argument i.e. the main class expects the command line argument to be converted to an int and I am passing a String value that cannot be converted to int)
However, the main class that I am testing, if the command line argument cannot be converted to a int, than I throw IllegalArgumentException. However, the JUnit does not show the testMain() method as Error or Failure. I don't think my setup is right for the JUnit class. Can anyone please guide me where I am going wrong
To test your class main method simply write something like:
#Test(expected = IllegalArgumentException.class)
public void testMainWithBadCommandLine()
{
YourClass.main(new String[] { "NaN" });
}
Change the main() method to something like this:
public static void main(String[] args)
{
MyClass myclass = new MyClass(args);
myclass.go();
}
Move the code that was in main() to the new method go(). Now, your test method can do this:
public void myClassTest()
{
String[] args = new String[]{"one", "two"}; //for example
MyClass classUnderTest = new MyClass(testArgs);
classUnderTest.go();
}
Firstly the arguments should be in the program arguments section. Normally the launching point of the application that's the main method doesn't need to be tested if you design the app to be testable.
Refactor the class
public static class ArgumentValidator
{
public static boolean nullOrEmpty(String [] args)
{
if(args == null || args.length == 0)
{
throw new IllegalArgumentException(msg);
}
//other methods like numeric validations
}
}
You can now easily test the nullOrEmpty method using junit like
#Test(expected = IllegalArgumentException.class)
public void testBadArgs()
{
ArgumentValidator.nullOrEmpty(null);
}
I think this is a better approach