How to create own annotation for junit that will skip test if concrete exception was thrown during execution?

Question

My application have several execution modes, and in 1 mode it is normal that some of my tests will throw a concrete exception. I need to annotate this methods with something

Answer 1

What about using JUnit Extensions?

The following example is taken from their Tutorial.

It provides aditional annotations for Prerequisites (@Prerequisite): Ignore tests based on conditions.

The required approach would be to check this during running tests. So you can simply add a @Prerequisite(requires="") annotation.

public class TestFillDatabase {
    @Prerequisite(requires = "databaseIsAvailable")
    @Test public void fillData() {
        // ...
    }

    public boolean databaseIsAvailable() {
        boolean isAvailable = ...;
        return isAvailable;
    }
}
public class TestFillDatabase {
    @Prerequisite(requires = "databaseIsAvailable")
    @Test public void fillData() {
        // ...
    }
    public boolean databaseIsAvailable() {
        boolean isAvailable = ...;
        return isAvailable ;
    }
}

This specified methods with @Prerequisite(requires = "databaseIsAvailable") must be a public method, returning a boolean or Boolean value.

If these methods will be consolidated in helper classes, you can also specify static methods within a class to be called using @Prerequisite(requires = "databaseIsAvailable", callee="DBHelper").

public class TestFillDatabase {
    @Prerequisite(requires = "databaseIsAvailable", callee="DBHelper")
    @Test public void fillData() {
        // ...
    }
}
public class DBHelper {
    public static boolean databaseIsAvailable() {
        boolean isAvailable = ...;
        return isAvailable ;
    }
}

Answer 2

Also using the Assume class (since jUnit 4.4), you can use assumeNoException():

try{
    base.evaluate();
} catch (ConcreteException e) {
    Assume.assumeNoException("Concrete exception: skipping test", e);
}

Answer 3

I don't think that such a feature is available out of the box, but it should be pretty easy to implement with custom TestRule and Assume, something like this:

@Rule
public TestRule skipRule = new TestRule() {
    public Statement apply(final Statement base, Description desc) {
         if (desc.getAnnotation(SkipOnFail.class) == null) return base;

         return new Statement() {
             public void evaluate() throws Throwable {
                 try {
                     base.evaluate();
                 } catch (MyExceptoion ex) {
                     Assume.assumeTrue(false);
                 }
             }
         };
    }
};

Answer 4

I searched for the docs about JUnit and it appears that from version 4.9 they have introduced what they call test rules (see TestRule). You may start from this.

The ExpectedException class marked as @Rule could be of some help in order to check for exceptions thrown but not mandatory for the test to pass.

For more advanced usage I cannot say for the moment as I've just discovered it.