CollectionAssert in jUnit?

Question

Is there a jUnit parallel to NUnit's CollectionAssert?

Answer 1

Using JUnit 4.4 you can use assertThat() together with the Hamcrest code (don't worry, it's shipped with JUnit, no need for an extra .jar) to produce complex self-describing asserts including ones that operate on collections:

import static org.junit.Assert.assertThat; import static org.junit.matchers.JUnitMatchers.*; import static org.hamcrest.CoreMatchers.*;  List<String> l = Arrays.asList("foo", "bar"); assertThat(l, hasItems("foo", "bar")); assertThat(l, not(hasItem((String) null))); assertThat(l, not(hasItems("bar", "quux"))); // check if two objects are equal with assertThat()  // the following three lines of code check the same thing. // the first one is the "traditional" approach, // the second one is the succinct version and the third one the verbose one  assertEquals(l, Arrays.asList("foo", "bar"))); assertThat(l, is(Arrays.asList("foo", "bar"))); assertThat(l, is(equalTo(Arrays.asList("foo", "bar")))); 

Using this approach you will automagically get a good description of the assert when it fails.

Answer 2

Not directly, no. I suggest the use of Hamcrest, which provides a rich set of matching rules which integrates nicely with jUnit (and other testing frameworks)