Using JUnit 4 with Groovy

Groovy has excellent support for Unit Testing with JUnit 3.8.2 and Mocking capabilties built right in. Currently, special support doesn't exist for JUnit 4 but its easy to use so long as you are using Groovy 1.1 (currently in beta) and Java 5+ (a requirement for annotations/Junit 4.x). Here is an example.

Make sure you are using Groovy 1.1 (we used beta-2) and JUnit 4.x (we used 4.4).

Simple Example

Let's test some of the built-in arithmetic operators in Groovy.

Our test class includes two tests additionIsWorking and divideByZero. The second of these is expected to fail with an ArithmeticException exception.

Running the test gives:

Parameterized Testing

JUnit 4.x includes the ability to have parameterized tests. Suppose we want to test the following program:

Here is what your code might look like. This example uses parameterization.

The output will look something like this: