Ant + JUnit: NoClassDefFoundError

Question

Ok, I'm frustrated! I've hunted around for a good number of hours and am still stumped.

Environment: WinXP, Eclipse Galileo 3.5 (straight install - no extra plugins).

So, I have a simple JUnit test. It runs fine from it's internal Eclipse JUnit run configuration. This class has no dependencies on anything. To narrow this problem down as much as possible it simply contains:

@Test
public void testX() {
    assertEquals("1", new Integer(1).toString());
}

No sweat so far. Now I want to take the super advanced step of running this test case from within Ant (the final goal is to integrate with Hudson).

So, I create a build.xml:

<project name="Test" default="basic">
    <property name="default.target.dir" value="${basedir}/target" />
    <property name="test.report.dir" value="${default.target.dir}/test-reports" />

    <target name="basic">
        <mkdir dir="${test.report.dir}" />
        <junit fork="true" printSummary="true" showOutput="true">
            <formatter type="plain" />
            <classpath>
                <pathelement path="${basedir}/bin "/>
            </classpath>
            <batchtest fork="true" todir="${test.report.dir}" >
                <fileset dir="${basedir}/bin">
                    <include name="**/*Test.*" />
                </fileset>
            </batchtest>
        </junit>
    </target>
</project>

${basedir} is the Java project name in the workspace that contains the source, classes and build file. All .java's and the build.xml are in ${basedir}/src. The .class files are in ${basedir}/bin.

I have added eclipse-install-dir/plugins/org.junit4_4.5.0.v20090423/junit.jar to the Ant Runtime Classpath via Windows / Preferences / Ant / Runtime / Contributed Entries. ant-junit.jar is in Ant Home Entries.

So, what happens when I run this insanely complex target? My report file contains:

Testsuite: com.xyz.test.RussianTest
Tests run: 1, Failures: 0, Errors: 1, Time elapsed: 0 sec

Testcase: initializationError took 0 sec
Caused an ERROR
org/hamcrest/SelfDescribing
java.lang.NoClassDefFoundError: org/hamcrest/SelfDescribing
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(Unknown Source)
    at java.security.SecureClassLoader.defineClass(Unknown Source)
    at java.net.URLClassLoader.defineClass(Unknown Source)
    at java.net.URLClassLoader.access$000(Unknown Source)
    at java.net.URLClassLoader$1.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClassInternal(Unknown Source)
    at java.lang.reflect.Constructor.newInstance(Unknown Source)
    Caused by: java.lang.ClassNotFoundException: org.hamcrest.SelfDescribing
    at java.net.URLClassLoader$1.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClassInternal(Unknown Source)

What is this org.hamcrest.SelfDescribing class? Something to do with mocks? OK, fine. But why the dependency? I'm not doing anything at all with it. This is literally a Java project with no dependencies other than JUnit.

Stumped (and frustrated)!!

Solution 1

I downloaded JUnit 4.7 and put junit-4.7.jar in my build path (instead of the older version). That solved it. I didn't touch ant.

Solution 2

add also hamcrest.jar to your testing classpath

Solution 3

I found the reason to an identical problem, but only when running the test with Ant on the commandline.

You might want to run Ant in debug mode (ant -d) and watch out for this statement:

[junit] Implicitly adding /usr/share/ant/lib/junit4.jar:...

Im my case, this JAR was added to the end of my classpath when running the test and overrode my JUnit reference in my Ant script.

It turned out that my Ant installation was bundled with a set of older JUnit libs. I had to remove the junit4.jar above in order to make my Ant classpath ref to take effect.

Solution 4

Faced exactly the same problem in eclipse but resolved it following the given steps

1. Go to Preferences | Java | JUnit
2. Click "Add Package" and add "org.hamcrest.*"

Voila... the problem is gone..

Solution 5

I had same problem with jUnit 4.11, Ant and Ivy. This code works for me but you have to make sure that you have hamcrest-core-1.3.jar (for jUnit 4.11) in your lib folder.

<property name="lib.dir">lib</property>
<property name="test.dir">src/test/java</property>
<property name="build.test">build/test/java</property>

<path id="test.path.id">
    <path location="${build.test}" />
    <path refid="lib.path.id" />
</path>

<path id="lib.path.id">
    <fileset dir="${lib.dir}" />
</path>

<!-- ================================= 
              Runs Tests         
================================= -->
<target name="junit">
    <junit>
        <classpath refid="test.path.id" />
        <batchtest>
            <fileset dir="${test.dir}" />
        </batchtest>
        <formatter type="plain" usefile="false" />
    </junit>
</target>

View more solutions

Comments

[Raul Luna]

In my case, this problem came up when moved a project from java 1.6 to java 1.5. I don't know if this matters.

[SteveT]

Thanks for all the replies. We're on to something, but not solved yet. I downloaded junit-4.6.jar from junit.org. It contains the org.hamcrest classes. I add that jar to the classpath and still get the same error. I do not have a stray Ant or JUnit install floating around someplace.

[SteveT]

This is crazy. More info... The Java project has the Eclipse-standard JUnit4 library. That library includes two jars - plugins/org.junit4_4.5.0.v20090423/junit.jar plugins/org.hamcrest.core_1.1.0.v20090501071000.jar In my Ant Global Entries I have added those two jars. When I run the task I get the exact same error. A NCDFE on org.hamcrest.SelfDescribing. Completely baffled...

[Kushal Paudyal]

This solved my problem. I actually had to do fork="off". I spent my three days trying to figure out how to solve, and finally after trying your suggestion got that thing working.Thanks a bunch.

[Conrad.Dean]

cd lib and wget http://repo2.maven.org/maven2/org/hamcrest/hamcrest-all/1.1/‌​hamcrest-all-1.1.jar for anyone else that got here from Google

[Anu Shibin Joseph Raj]

Same case with me. I removed ant-junit4.jar from ANT lib and it worked.