Eclipse Plug-in Test execution for JUnit4

Question

I have a JUnit4 test suite and I want to execute it under the JUnit Plug-in Test run configuration.

It passes successfully when running through the JUnit Test configuration, but for plug-in conf it fails in different ways.

For example if I use JUnit4TestAdapter it fails with ClassCastException, and if I trying to run it only through the @RunWith annotation it wrotes "No methods found" error. For both implementations I use JUnit4 Test Runner setting inside run configuration.

I use

• Eclipse Neon.1a Release (4.6.1)
• Jdk 1.8
• linking JUnit 4.1 lib to the plugin.

For first case it seems that Eclipse proceed to use the JUnit3 version when executing the suite. Here it is:

@RunWith(Suite.class)
@SuiteClasses({ DndTest.class })
public class JSTestSuite {

    public static Test suite() {
        return new JUnit4TestAdapter(JSTestSuite.class);
    }
}

And exception is:

java.lang.ClassCastException: junit.framework.JUnit4TestAdapter cannot be cast to junit.framework.Test
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.getTest(RemoteTestRunner.java:403)

While starting the test I have a strange log message in console:

!ENTRY org.eclipse.update.configurator 2017-05-04 17:58:57.279
!MESSAGE Could not install bundle ../../platform/eclipse/plugins/org.eclipse.jdt.junit4.runtime_1.1.600.v20160505-0715.jar   No match is available for the required execution environment: J2SE-1.5

I see this lib is on the place, but I can't understand why it failing to be loaded. For JUnit3 Test Runner setting junit3 lib is loaded ok. There are some bugs related to such issues (like this) but it is really hard to understand what can I do in this case.

For second case I just try to execute simple JUnit4 case without using the JUnit4TestAdapter, but it can't find any methods.

Reloading of eclipse and renaming of the methods didn't help. What can I do in this case?

Answer 1

I found that there are couple of issues. First I consider one by one to solve the issue.

Issue#1: No match is available for the required execution environment: J2SE-1.5

Issue#2: java.lang.ClassCastException: junit.framework.JUnit4TestAdapter cannot be cast to junit.framework.Test

Solution for Issue#1:

First solution:

1. Right-click on your project
2. Click Properties
3. Click the "Java Compiler" option on the left menu
4. Under JDK compliance section on the right, change it to "1.8"

Second solution:

If you use maven in your project, then you can change pom.xml file as below:

<build>
    <pluginManagement>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.1</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
        </plugins>

    </pluginManagement>
</build>

Resource Link: Maven "build path specifies execution environment J2SE-1.5", even though I changed it to 1.7

Solution for Issue#2:

JUnit runner has a dependency on JUnit 3.8. It won't be used but without it, the whole platform can't be initialized. So you need 2 versions like the following

Check you have below plugins

org.eclipse.xtext.xbase.junit
org.junit (3.8.2)
org.junit (4.8.2)

How to check for JUnit?

In eclipse, please check in 2 sections.

1. Check your Project Properties->Java Build Path->Libraries (tab)
2. Check you Project's Run Configurations->JUnit->Classpath (tab)

How to fix?

To fix the error make sure you have org.junit 3.8 in the target platform!

All credit goes to A Paul.

Resource Link:

https://stackoverflow.com/a/21334162/2293534

Aaron Digulla has commented like below:

Despite the fact that org.eclipse.xtext.junit4 imports org.junit 4.5.0, org.eclipse.xtext.junit (note the missing "4" at the end) seems to have a dependency to JUnit 3.8. After adding the old, outdated JUnit bundle, the plugin tests started.