java.lang.NoClassDefFoundError: org/hamcrest/SelfDescribing

Add hamcrest-all-X.X.jar to your classpath.

Latest version as of Feb 2015 is 1.3: http://code.google.com/p/hamcrest/downloads/detail?name=hamcrest-all-1.3.jar&can=2&q=

According to the JUnit GitHub team website (https://github.com/junit-team/junit/wiki/Download-and-Install), junit.jar and hamcrest-core.jar are both needed in the classpath when using JUnit 4.11.

Here is the Maven dependency block for including junit and hamcrest.

<dependency>
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>4.1.2</version>
    <scope>test</scope>
</dependency>
<!-- Needed by junit -->
<dependency>
    <groupId>org.hamcrest</groupId>
    <artifactId>hamcrest-all</artifactId>
    <version>1.3</version>
    <scope>test</scope>
</dependency>

A few steps you have to follow:

Right click on the project. Choose Build Path Then from its menu choose Add Libraries. Choose JUnit then click Next. Choose JUnit4 then Finish.

Works for me: IntelliJ IDEA 13.1.1, JUnit4, Java 6

I changed the file in project path: [PROJECT_NAME].iml

Replaced:

  <library>
    <CLASSES>
      <root url="jar://$APPLICATION_HOME_DIR$/lib/junit-4.11.jar!/" />
    </CLASSES>
    <JAVADOC />
    <SOURCES />
  </library>

By:

  <library name="JUnit4">
    <CLASSES>
      <root url="jar://$APPLICATION_HOME_DIR$/lib/junit-4.11.jar!/" />
      <root url="jar://$APPLICATION_HOME_DIR$/lib/hamcrest-core-1.3.jar!/" />
      <root url="jar://$APPLICATION_HOME_DIR$/lib/hamcrest-library-1.3.jar!/" />
    </CLASSES>
    <JAVADOC />
    <SOURCES />
  </library>

So the final .iml file is:

<?xml version="1.0" encoding="UTF-8"?>
<module type="JAVA_MODULE" version="4">
  <component name="NewModuleRootManager" inherit-compiler-output="true">
    <exclude-output />
    <content url="file://$MODULE_DIR$">
      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
      <sourceFolder url="file://$MODULE_DIR$/tests" isTestSource="true" />
    </content>
    <orderEntry type="inheritedJdk" />
    <orderEntry type="sourceFolder" forTests="false" />
    <orderEntry type="module-library">
      <library name="JUnit4">
        <CLASSES>
          <root url="jar://$APPLICATION_HOME_DIR$/lib/junit-4.11.jar!/" />
          <root url="jar://$APPLICATION_HOME_DIR$/lib/hamcrest-core-1.3.jar!/" />
          <root url="jar://$APPLICATION_HOME_DIR$/lib/hamcrest-library-1.3.jar!/" />
        </CLASSES>
        <JAVADOC />
        <SOURCES />
      </library>
    </orderEntry>
  </component>
</module>

P.S.: save the file and don't let to IntelliJ Idea reload it. Just once.

You need junit-dep.jar because the junit.jar has a copy of old Hamcrest classes.

Just in case there's anyone here using netbeans and has the same problem, all you have to do is

Right click on TestLibraries

Click on Add Library

Select JUnit and click add library

Repeat the process but this time click on Hamcrest and the click add library

This should solve the problem

This problem is because of your classpath miss hamcrest-core-1.3.jar. To resolve this add hamcrest-core-1.3.jar as you add junit-4.XX.jar into your classpath.

At first, I encounter this problem too, but after I refer to the official site and add hamcrest-core-1.3.jar into classpath with command line, it works properly finally.

javac -d ../../../../bin/ -cp ~/libs/junit-4.12.jar:/home/limxtop/projects/algorithms/bin  MaxHeapTest.java 

java -cp ../../../../bin/:/home/limxtop/libs/junit-4.12.jar:/home/limxtop/libs/hamcrest-core-1.3.jar org.junit.runner.JUnitCore com.limxtop.heap.MaxHeapTest

You need to add the hamcrest-core JAR to the classpath as described here: https://github.com/junit-team/junit4/wiki/Download-and-Install

As a general rule, always make sure hamcrest is before any other testing libraries on the classpath, as many such libraries include hamcrest classes and may therefore conflict with the hamcrest version you're using. This will resolve most problems of the type you're describing.

the simplest way of solving the problem to begin with is copying latest version of hamcrest-code.jar into your CLASSPATH that is the file you store other .jar files needed for compilation and running of your application.

that could be e.g.: C:/ant/lib

It sounds like a classpath issue, so there are a few different ways to go about it. Where does org/hamcret/SelfDescribing come from? Is that your class or in a different jar?

Try going to your project Build Path and on the Libraries tab, add a Library. You should be able to choose JUnit to your project. This is a little bit different than just having the JUnit jar file In your project.

In your Run Configuration for the JUnit test, check the Classpath. You could probably fix this by adding making sure your Classpath can see that SelfDescribing class there. The Run option in Eclipse has a different set of options for the JUnit options.

If this problem arise in a RCP project it can be because JUnit has been explicitly imported.

Check the editor for your plugin.xml under Dependencies tab, remove the org.junit from the Imported Packages and add org.junit to the Required Plug-ins.

The problem is when you set up eclipse to point to JRE instead of JDK. JRE has junit4.jar in the lib/ext folder, but not hamcrest.jar :) So the solution is to check installed JREs in Eclipse, remove the existing one and create a new one pointing to your JDK.

This happens when you run Ant via command line. The implicit user dependencies are added in the classpath at the end and take precedence over the project-added classpath. Run Ant with -nouserlib flag. The implicit dependencies would be excluded from the classpath.

There is a better answer to solve this problem. add dependency

<dependency>
    <groupId>org.hamcrest</groupId>
    <artifactId>hamcrest-all</artifactId>
    <version>1.3</version>
    <scope>test</scope>
</dependency>

The hamcrest-core-1.3.jar available on maven repository is deprecated.

Download working hamcrest-core-1.3.jar from official Junit4 github link . If you want to download from maven repository, use latest hamcrest-XX.jar.

<dependency>
    <groupId>org.hamcrest</groupId>
    <artifactId>hamcrest</artifactId>
    <version>2.2</version>
    <scope>test</scope>
</dependency>

I had the same problem, the solution is to add in build path/plugin the jar org.hamcrest.core_1xx, you can find it in eclipse/plugins.

A few steps you have to follow:

Right click on the project.

Choose Build Path & then from its menu choose Add Libraries.

Choose JUnit then click Next.

Choose JUnit4 then Finish.

This works for me...

"java.lang.SecurityException: class" org.hamcrest.Matchers "'s signer information does not match signer information of other classes in the same package"

Do it: Right-click on your package click on Build Path -> Configure Build Path Click on the Libraries tab Remove JUnit Apply and close Ready.

Try adding the jar files manually or try with force update with the latest hamcrest.jar