JUnit Maven Dependency

<dependency>
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>4.12</version>
</dependency>

Basic annotations @Before, @After, @BeforeClass, @AfterClass

Executed before every @Test method

@Before 
public void setUp() {
}

Executed after every @Test method

@After 
public void tearDown() { 
}

Executed once before all @Test methods

@BeforeClass 
public void setUpBeforeClass() { 
}

Executed once after all @Test methods

@AfterClass 
public void tearDownAfterClass() { 
}

Test methods annotation. @Test

@Test 
public void someTest() { 
}

For time limited (in milliseconds) tests use @Test(timeout = 5000)

For testing of exceptions use @Test(expected = SomeSpecificException.class)

Parameterized tests

The class should be declared with @RunWith(Parameterized.class) annotation.

@RunWith(Parameterized.class)
public class SomeTestClassName {
}

You should provide the method with @Parameters annotation that returns collection of arrays. Every test will be executed with each array as with a parameters set

@Parameters
public static Collection<Object[]> params() {
    return someParams;
}

You have to have the constructor method with arguments corresponding to Object[] mentioned above.

private SomeParamType1 param1;
private SomeParamType2 param2;
private SomeParamType3 param3;
...
										
public SomeTestClassName( SomeParamType1 param1, SomeParamType2 param2, SomeParamType3 param3) {
    this.param1 = param1;
    this.param2 = param2;
    this.param3 = param3;
	...
}

JUnit Assertions

AssertTrue("Some message if not true", true);
AssertEquals("Some message if Fail", expectedResult, ActualResult);

JUnit Test suites

You can use Suite classes as containers for your tests. @Suite.SuiteClasses defines classes that are included into the suite and the order of execution.

@RunWith(Suite.class)
@Suite.SuiteClasses({SomeTestClassName1.class, SomeTestClassName2.class, 
			SomeTestClassName3.class, ...})										
public class SomeTestSuiteName {
}

Leave the suite class empty

Need more?

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