JUnitThe Other Stuff

Charles Sharp, OCIMay 9, 2013

Thursday, June 6, 13

Yay! An Ad!Java Testing with JUnit

www.ociweb.com/training/Java-Testing-with-JUnit

July 9 - July 18T/Th, 5:30 – 8:30

Mention the JUG and get 10% off!

Thursday, June 6, 13

 

JUnit StatusRelease Date4.11 Nov 14, 20124.10 Sep 29, 20124.9 Aug 22, 20114.8 Nov 30, 20094.7 Jul 27, 20094.6 Apr 13, 20094.5 Aug 8, 20084.4 Jul 19, 20074.3 Mar 20, 20074.2 Nov 16, 20064.1 May 2, 20064.0 Feb 16, 20063.8.2 Mar 3, 20063.8.1 Sep 4, 2002

Thursday, June 6, 13

JUnit Annotations• @Before

• @BeforeClass

• @After

• @AfterClass

• @Ignore

• @Test

• @Test(timeout=500)

• @Test(expected=<Exception>.class)

Thursday, June 6, 13

Everyone Uses • @Before fka setUp()

• @After fka tearDown()

• @Test fka test<something>()

Thursday, June 6, 13

Some Use• @BeforeClass

• @AfterClass

Thursday, June 6, 13

Quiz!

Thursday, June 6, 13

Tonight• Assumptions

• Categories

• Parameterized Testing

• Parameter

• Theory

• Rules

• Hamcrest Matchers

Thursday, June 6, 13

Everyone Uses Asserts• assertEquals(...) / assertArrayEquals(...)

• assertNull(...) / assertNonNull(...)

• assertSame(...) / assertNotSame(...)

• assertTrue(...) / assertFalse(...)

• fail(“Not implemented yet.”);

Thursday, June 6, 13

Not a whole lot of folk useassertThat([java.lang.string Reason],

T actual, org.hamcrest.matcher<T> matcher)

(more on Hamcrest in just a bit)

Thursday, June 6, 13

Hardly anyone uses • Assume:

• assumeNoException(...)

• assumeNotNull (...)

• assumeThat(...) // used a lot in @Theory

• assumeTrue(...)

Unlike Asserts, if an assumption is wrong, the test is halted and ignored.

Thursday, June 6, 13

@Category

• Canonical example is fast and slow

• Browser: Firefox, Chrome, Opera, others

• Database: DB2, Oracle, &c...

Gives the ability to group tests.- exclude a group- include a group

Thursday, June 6, 13

Category Example

Thursday, June 6, 13

Parameterized Testing

• @RunWith(Parameters.class)

• @RunWith(Theory.class)

Thursday, June 6, 13

Parameter.class• Pros:

• Quick to write

• No need to establish relationships

• Cons:

• Must detail all data

Thursday, June 6, 13

Parameter.class• Static Method to Generate Test

Data

• Single Constructor that stores test data

• Test(s)

Thursday, June 6, 13

Parameterized Example

Thursday, June 6, 13

Theory.class• Cons:

• Not (typically) quick to write

• Must understand data relationships

• Pros?:

• Don’t need to detail all data

Thursday, June 6, 13

Theory.class

• Method to generate and return test data

• Theory(s)

Thursday, June 6, 13

Theory Example

Thursday, June 6, 13

Rules• Add information to test results.

• Access information about a test before it is run

• Modify a test before running it.

• Modify test results.

Thursday, June 6, 13

Rules Examples

Thursday, June 6, 13

Hamcrest

What an odd name...

Thursday, June 6, 13

Matchers

or not.

Thursday, June 6, 13

Hamcrest Matchers• hamcrest.org (/JavaHamcrest/javadoc/1.3/)

• General purpose matching library for Java, Python, Ruby, Objective-C, PHP, and Erlang (What? No Haskell?)

• Provides readability

• code

• error messages

Thursday, June 6, 13

Hamcrest Cheat Sheet

http://www.marcphilipp.de/downloads/posts/2013-01-02-hamcrest-quick-reference/Hamcrest-1.3.pdf

Thursday, June 6, 13

Matcher Types• General Purpose:

is(T), not(T), any(T), isIn(T), instanceOf(Class)

• Strings:

startsWith(S), endsWith(S)equalToIgnoringCase(S), equalToIgnoringWhiteSpace(S)isEmptyString(), isEmptyOrNullString()

Thursday, June 6, 13

More matchers• Iterables:

contains(E ...) // (oh, boy, howdy...)

containsInAnyOrder(T ...)

hasItem(T) // Yay!

hasItems(T ...)

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And more...• Collections:

hasSize(int)

empty()

emptyCollectionOf(Class<E>)

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And many more...• Arrays

• Comparable

• Classes

• DOM

• Maps

• Numbers

Thursday, June 6, 13

Tonight• Assumptions

• Categories

• Parameterized Testing

• Parameter

• Theory

• Rules

• Hamcrest Matchers

Thursday, June 6, 13