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How to run test methods in specific order in JUnit4?

I want to execute test methods which are annotated by @Test in specific order.

For example:

public class MyTest {
    @Test public void test1(){}
    @Test public void test2(){}

I want to ensure to run test1() before test2() each time I run MyTest, but I couldn't find annotation like @Test(order=xx).

I think it's quite important feature for JUnit, if author of JUnit doesn't want the order feature, why?

Source: (StackOverflow)

Maven does not find JUnit tests to run

I have a maven program, it compiles fine. When I run mvn test it does not run any tests (under TESTs header says There are no tests to run.).

I've recreated this problem with a super simple setup which I will include below as well as the output when run with -X.

The unit tests run fine from eclipse (both with its default junit package and when I instead include the junit.jar downloaded by maven). Also mvn test-compile correctly creates the class under test-classes. I am running this on OSX 10.6.7 with Maven 3.0.2 and java 1.6.0_24.

Here is the directory structure:



<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="" xmlns:xsi="" xsi:schemaLocation="">
    <name>My Program</name>

public class ClassUnderTest {

    public int functionUnderTest(int n) {
        return n;


import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;

public class ClassUnderTestTests {

    private ClassUnderTest o;

    public void setUp() {
        o = new ClassUnderTest();

    public void testFunctionUnderTest_testCase1() {
        Assert.assertEquals(1, o.functionUnderTest(1));

    public void testFunctionUnderTest_testCase2() {
        Assert.assertEquals(2, o.functionUnderTest(2));

End of mvn -X test:

[DEBUG] Configuring mojo org.apache.maven.plugins:maven-surefire-plugin:2.7.1:test from plugin realm ClassRealm[plugin>org.apache.maven.plugins:maven-surefire-plugin:2.7.1, parent: sun.misc.Launcher$AppClassLoader@5224ee]
[DEBUG] Configuring mojo 'org.apache.maven.plugins:maven-surefire-plugin:2.7.1:test' with basic configurator -->
[DEBUG]   (s) basedir = /Users/aaron/Programs/my_program
[DEBUG]   (s) childDelegation = false
[DEBUG]   (s) classesDirectory = /Users/aaron/Programs/my_program/target/classes
[DEBUG]   (s) disableXmlReport = false
[DEBUG]   (s) enableAssertions = true
[DEBUG]   (s) forkMode = once
[DEBUG]   (s) junitArtifactName = junit:junit
[DEBUG]   (s) localRepository =        id: local
      url: file:///Users/aaron/.m2/repository/
   layout: none

[DEBUG]   (f) parallelMavenExecution = false
[DEBUG]   (s) pluginArtifactMap = {org.apache.maven.plugins:maven-surefire-plugin=org.apache.maven.plugins:maven-surefire-plugin:maven-plugin:2.7.1:, org.apache.maven.surefire:surefire-booter=org.apache.maven.surefire:surefire-booter:jar:2.7.1:compile, org.apache.maven.surefire:surefire-api=org.apache.maven.surefire:surefire-api:jar:2.7.1:compile, org.apache.maven.surefire:maven-surefire-common=org.apache.maven.surefire:maven-surefire-common:jar:2.7.1:compile, org.apache.maven.shared:maven-common-artifact-filters=org.apache.maven.shared:maven-common-artifact-filters:jar:1.3:compile, org.codehaus.plexus:plexus-utils=org.codehaus.plexus:plexus-utils:jar:2.0.5:compile, junit:junit=junit:junit:jar:3.8.1:compile, org.apache.maven.reporting:maven-reporting-api=org.apache.maven.reporting:maven-reporting-api:jar:2.0.9:compile}
[DEBUG]   (s) printSummary = true
[DEBUG]   (s) project = MavenProject: my_group:my_program:1.0-SNAPSHOT @ /Users/aaron/Programs/my_program/pom.xml
[DEBUG]   (s) projectArtifactMap = {junit:junit=junit:junit:jar:4.8.1:test}
[DEBUG]   (s) redirectTestOutputToFile = false
[DEBUG]   (s) remoteRepositories = [       id: central
   layout: default
snapshots: [enabled => false, update => daily]
 releases: [enabled => true, update => never]
[DEBUG]   (s) reportFormat = brief
[DEBUG]   (s) reportsDirectory = /Users/aaron/Programs/my_program/target/surefire-reports
[DEBUG]   (s) session = org.apache.maven.execution.MavenSession@dfbb43
[DEBUG]   (s) skip = false
[DEBUG]   (s) skipTests = false
[DEBUG]   (s) testClassesDirectory = /Users/aaron/Programs/my_program/target/test-classes
[DEBUG]   (s) testFailureIgnore = false
[DEBUG]   (s) testNGArtifactName = org.testng:testng
[DEBUG]   (s) testSourceDirectory = /Users/aaron/Programs/my_program/src/test/java
[DEBUG]   (s) trimStackTrace = true
[DEBUG]   (s) useFile = true
[DEBUG]   (s) useManifestOnlyJar = true
[DEBUG]   (s) workingDirectory = /Users/aaron/Programs/my_program
[DEBUG] -- end configuration --
[INFO] Surefire report directory: /Users/aaron/Programs/my_program/target/surefire-reports
[DEBUG] Setting system property [user.dir]=[/Users/aaron/Programs/my_program]
[DEBUG] Setting system property [localRepository]=[/Users/aaron/.m2/repository]
[DEBUG] Setting system property [basedir]=[/Users/aaron/Programs/my_program]
[DEBUG] Using JVM: /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home/bin/java
[DEBUG] Using manager EnhancedLocalRepositoryManager with priority 10 for /Users/aaron/.m2/repository
[DEBUG] dummy:dummy:jar:1.0 (selected for null)
[DEBUG]   org.apache.maven.surefire:surefire-booter:jar:2.7.1:compile (selected for compile)
[DEBUG]     org.apache.maven.surefire:surefire-api:jar:2.7.1:compile (selected for compile)
[DEBUG] Adding to surefire booter test classpath: /Users/aaron/.m2/repository/org/apache/maven/surefire/surefire-booter/2.7.1/surefire-booter-2.7.1.jar Scope: compile
[DEBUG] Adding to surefire booter test classpath: /Users/aaron/.m2/repository/org/apache/maven/surefire/surefire-api/2.7.1/surefire-api-2.7.1.jar Scope: compile
[DEBUG] Using manager EnhancedLocalRepositoryManager with priority 10 for /Users/aaron/.m2/repository
[DEBUG] dummy:dummy:jar:1.0 (selected for null)
[DEBUG]   org.apache.maven.surefire:surefire-junit4:jar:2.7.1:test (selected for test)
[DEBUG]     org.apache.maven.surefire:surefire-api:jar:2.7.1:test (selected for test)
[DEBUG] Adding to surefire test classpath: /Users/aaron/.m2/repository/org/apache/maven/surefire/surefire-junit4/2.7.1/surefire-junit4-2.7.1.jar Scope: test
[DEBUG] Adding to surefire test classpath: /Users/aaron/.m2/repository/org/apache/maven/surefire/surefire-api/2.7.1/surefire-api-2.7.1.jar Scope: test
[DEBUG] Test Classpath :
[DEBUG]   /Users/aaron/Programs/my_program/target/test-classes
[DEBUG]   /Users/aaron/Programs/my_program/target/classes
[DEBUG]   /Users/aaron/.m2/repository/junit/junit/4.8.1/junit-4.8.1.jar
[DEBUG] Using manager EnhancedLocalRepositoryManager with priority 10 for /Users/aaron/.m2/repository
[DEBUG] dummy:dummy:jar:1.0 (selected for null)
[DEBUG]   org.apache.maven.surefire:surefire-booter:jar:2.7.1:compile (selected for compile)
[DEBUG]     org.apache.maven.surefire:surefire-api:jar:2.7.1:compile (selected for compile)
[DEBUG] Adding to surefire booter test classpath: /Users/aaron/.m2/repository/org/apache/maven/surefire/surefire-booter/2.7.1/surefire-booter-2.7.1.jar Scope: compile
[DEBUG] Adding to surefire booter test classpath: /Users/aaron/.m2/repository/org/apache/maven/surefire/surefire-api/2.7.1/surefire-api-2.7.1.jar Scope: compile
Forking command line: /bin/sh -c cd /Users/aaron/Programs/my_program && /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home/bin/java -jar /Users/aaron/Programs/my_program/target/surefire/surefirebooter6118081963679415631.jar /Users/aaron/Programs/my_program/target/surefire/surefire4887918564882595612tmp /Users/aaron/Programs/my_program/target/surefire/surefire9012255138269731406tmp

 T E S T S
There are no tests to run.

Results :

Tests run: 0, Failures: 0, Errors: 0, Skipped: 0

[INFO] ------------------------------------------------------------------------
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 2.089s
[INFO] Finished at: Mon May 30 12:03:09 EDT 2011
[INFO] Final Memory: 7M/62M
[INFO] ------------------------------------------------------------------------

Source: (StackOverflow)

differences between 2 JUnit Assert classes

The JUnit framework contains 2 Assert classes (in different packages, obviously) and the methods on each appear to be very similar. Can anybody explain why this is?

The classes I'm referring to are: junit.framework.Assert and org.junit.Assert.

Source: (StackOverflow)

How to test a class that has private methods, fields or inner classes

How do I use JUnit to test a class that has internal private methods, fields or nested classes? It seems bad to change the access modifier for a method just to be able to run a test.

Source: (StackOverflow)

Getting "NoSuchMethodError: org.hamcrest.Matcher.describeMismatch" when running test in IntelliJ 10.5

I'm using JUnit-dep 4.10 and Hamcrest 1.3.RC2.

I've created a custom matcher that looks like the following:

public static class MyMatcher extends TypeSafeMatcher<String> {
    protected boolean matchesSafely(String s) {
        /* implementation */

    public void describeTo(Description description) {
        /* implementation */

    protected void describeMismatchSafely(String item, Description mismatchDescription) {

        /* implementation */

It works perfectly fine when run from the command line using Ant. But when run from IntelliJ, it fails with:

java.lang.NoSuchMethodError: org.hamcrest.Matcher.describeMismatch(Ljava/lang/Object;Lorg/hamcrest/Description;)V
    at org.hamcrest.MatcherAssert.assertThat(
    at org.hamcrest.MatcherAssert.assertThat(

My guess is that it's using the wrong hamcrest.MatcherAssert. How do I find which hamcrest.MatcherAssert it's using (ie which jar file it's using for hamcrest.MatcherAssert)? AFAICT, the only hamcrest jars in my classpath is 1.3.RC2.

Is IntelliJ IDEA using it's own copy of JUnit or Hamcrest?

How do I output the runtime CLASSPATH that IntelliJ is using?

Source: (StackOverflow)

Get name of currently executing test in JUnit 4

In JUnit 3, I could get the name of the currently running test like this:

public class MyTest extends TestCase
    public void testSomething()
        System.out.println("Current test is " + getName());

which would print "Current test is testSomething".

Is there any out-of-the-box or simple way to do this in JUnit 4?

Background: Obviously, I don't want to just print the name of the test. I want to load test-specific data that is stored in a resource with the same name as the test. You know, convention over configuration and all that.


Source: (StackOverflow)

IntelliJ IDEA with Junit 4.7 "!!! JUnit version 3.8 or later expected:"

When I attempt to run the following test in IntelliJ IDEA I get the message:

!!! JUnit version 3.8 or later expected:

It should be noted that this is an Android project I am working on in IntelliJ IDEA 9.

public class GameScoreUtilTest {
    public void testCalculateResults() throws Exception {
        final Game game = new Game();

        final Player player1 = new Player();
            final PlayedHole playedHole = new PlayedHole();
            game.getHoleScoreMap().put(player1, playedHole);
            final PlayedHole playedHole = new PlayedHole();
            game.getHoleScoreMap().put(player1, playedHole);
        final GameResults gameResults = GameScoreUtil.calculateResults(game);

        assertEquals(4, gameResults.getScore());

The full stack trace looks like this...

!!! JUnit version 3.8 or later expected:

java.lang.RuntimeException: Stub!
    at junit.runner.BaseTestRunner.<init>(
    at junit.textui.TestRunner.<init>(
    at junit.textui.TestRunner.<init>(
    at junit.textui.TestRunner.<init>(
    at com.intellij.rt.execution.junit.JUnitStarter.junitVersionChecks(
    at com.intellij.rt.execution.junit.JUnitStarter.canWorkWithJUnitVersion(
    at com.intellij.rt.execution.junit.JUnitStarter.main(
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(
    at java.lang.reflect.Method.invoke(
    at com.intellij.rt.execution.application.AppMain.main(

Process finished with exit code -3

Source: (StackOverflow)

Java: Is assertEquals(String, String) reliable?

I know that == has some issues when comparing two Strings. It seems that String.equals() is a better approach. Well, I'm doing JUnit testing and my inclination is to use assertEquals(str1, str2). Is this a reliable way to assert two Strings contain the same content? I would use assertTrue(str1.equals(str2)), but then you don't get the benefit of seeing what the expected and actual values are on failure.

On a related note, does anyone have a link to a page or thread that plainly explains the problems with str1 == str2?


Source: (StackOverflow)

Configuring IntelliJ IDEA for unit testing with JUnit

I feel like an idiot for asking this but I've wasted way too much time on this already.

I'm an old Eclipse user which makes starting a java project with JUnit obvious. Just start writing a test class and it offers to add any libraries and imports that the file needs.

I decided to try out IntelliJ this morning so downloaded the trial. The JUnit plugin is installed. I make a new Java project and I want to write a test case.

How do I add the junit.jar to my project? (I actually want to add it to every java project, now and forever more - is there a way of doing that?).

Source: (StackOverflow)

Changing names of parameterized tests

Is there a way to set my own custom test case names when using parameterized tests in JUnit4?

I'd like to change the default — [Test class].runTest[n] — to something meaningful.

Source: (StackOverflow)

How to run JUnit test cases from the command line

I would like to run JUnit test cases from the command line. How can I do this?

Source: (StackOverflow)

Conditionally ignoring tests in JUnit 4

OK, so the @Ignore annotation is good for marking that a test case shouldn't be run.

However, sometimes I want to ignore a test based on runtime information. An example might be if I have a concurrency test that needs to be run on a machine with a certain number of cores. If this test were run on a uniprocessor machine, I don't think it would be correct to just pass the test (since it hasn't been run), and it certainly wouldn't be right to fail the test and break the build.

So I want to be able to ignore tests at runtime, as this seems like the right outcome (since the test framework will allow the build to pass but record that the tests weren't run). I'm fairly sure that the annotation won't give me this flexibility, and suspect that I'll need to manually create the test suite for the class in question. However, the documentation doesn't mention anything about this and looking through the API it's also not clear how this would be done programmatically (i.e. how do I programatically create an instance of Test or similar that is equivalent to that created by the @Ignore annotation?).

If anyone has done something similar in the past, or has a bright idea of how else I could go about this, I'd be happy to hear about it.

Source: (StackOverflow)

How do you assert that a certain exception is thrown in JUnit 4 tests?

How can I use JUnit4 idiomatically to test that some code throws an exception?

While I can certainly do something like this:

public void testFooThrowsIndexOutOfBoundsException() {
  boolean thrown = false;

  try {
  } catch (IndexOutOfBoundsException e) {
    thrown = true;


I recall that there is an annotation or an or something that is far less kludgy and far more in-the-spirit of JUnit for these sorts of situations.

Source: (StackOverflow)

Why doesn't JUnit provide assertNotEquals methods?

Does anybody know why JUnit 4 provides assertEquals(foo,bar) but not assertNotEqual(foo,bar) methods?

It provides assertNotSame (corresponding to assertSame) and assertFalse (corresponding to assertTrue), so it seems strange that they didn't bother including assertNotEqual.

By the way, I know that JUnit-addons provides the methods I'm looking for. I'm just asking out of curiosity.

Source: (StackOverflow)

When do Java generics require instead of and is there any downside of switching?

Given the following example (using JUnit with Hamcrest matchers)

    Map<String, Class<? extends Serializable>> expected = null;
    Map<String, Class<java.util.Date>> result = null;
    assertThat(result, is(expected));

This does not compile with the JUnit AssertThat method signature of:

public static <T> void assertThat(T actual, Matcher<T> matcher)

The compiler error message is:

Error:Error:line (102)cannot find symbol method
    <? extends>>>)

However, if I change the assertThat method signature to:

public static <T> void assertThat(T result, Matcher<? extends T> matcher)

Then the compilation works.

So three questions:

  1. Why exactly doesn't the current version compile? Although I vaguely understand the covariance issues here, I certainly couldn't explain it if I had to.
  2. Is there any downside in changing the assertThat method to Matcher<? extends T>? Are there other cases that would break if you did that?
  3. Is there any point to the genericizing of the assertThat method in JUnit? The Matcher class doesn't seem to require it, since JUnit calls the matches method, which is not typed with any generic, and just looks like an attempt to force a type safety which doesn't do anything, as the Matcher will just not in fact match, and the test will fail regardless. No unsafe operations involved (or so it seems).

For reference, here is the JUnit implementation of assertThat:

public static <T> void assertThat(T actual, Matcher<T> matcher) {
	assertThat("", actual, matcher);

public static <T> void assertThat(String reason, T actual,
		Matcher<T> matcher) {
	if (!matcher.matches(actual)) {
		Description description= new StringDescription();
		description.appendText("\nExpected: ");
		description.appendText("\n     got: ").appendValue(actual)
		throw new java.lang.AssertionError(description.toString());

Source: (StackOverflow)