Getting “java.lang.NoClassDefFoundError: com/beust

问题:

I wanted to invoke testng programmatically. Not eclipse plug-in.

I have associated "testng-6.8.21.jar" and running through eclipse and i ran below code:

import org.testng.TestNG;

public class SampCls 
{
        public static void main(String[] args)
        {
            TestNG test=new TestNG();
        }
}

Getting below exception. How can i overcome this exception.

Exception in thread "main" java.lang.NoClassDefFoundError: com/beust/jcommander/ParameterException
    at SampCls.main(SampCls.java:12)
Caused by: java.lang.ClassNotFoundException: com.beust.jcommander.ParameterException
    at java.net.URLClassLoader$1.run(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)
    ... 1 more

回答1:

Change:

Class cls = Class.forName("TestSuite.TestCases.AddContactHappyPath").getClass();
test.setTestClasses(new Class[] { cls });

By:

 test.setTestClasses(new Class[] { AddContactHappyPath.class });

All code is

import org.testng.TestNG;
import com.xxx.test.others.AddContactHappyPath;

public class SampCls {
    public static void main(String[] args) throws ClassNotFoundException {
        TestNG test = new TestNG();
         test.setTestClasses(new Class[] { AddContactHappyPath.class });
         test.run();
    }
}

TestNG code is:

import org.testng.annotations.*;

public class AddContactHappyPath {

    @Test()
    public void AddContactHappyPathTest() {
        System.out.println("hello world");
    }
}

Console result:

[TestNG] Running:
  Command line suite

hello world

===============================================
Command line suite
Total tests run: 1, Failures: 0, Skips: 0
===============================================

回答2:

If you use a Maven project, you need add this dependancy:

<dependency>
    <groupId>com.beust</groupId>
    <artifactId>jcommander</artifactId>
    <version>1.48</version>
</dependency>

the class com/beust/jcommander/ParameterException is inside

If you use a project without Maven you need add this jar file at your classpath:

jcommander-1.48.jar

You can download this jar file on central.maven.org -> jcommander-1.48.jar

回答3:

As @sgrillon correctly pointed out, you need the correct Maven dependency, but also the shade plugin (https://maven.apache.org/plugins/maven-shade-plugin) to package a Uber-jar including all Maven dependencies for easy execution. This is what should be included in your pom.xml:

...
  <dependencies>
    <dependency>
      <groupId>com.beust</groupId>
      <artifactId>jcommander</artifactId>
      <version>1.48</version>
    </dependency>
  </dependencies>
...
    <plugins>
      ...
      <plugin>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>3.1</version>
        <configuration>
          <source>1.8</source>
          <target>1.8</target>
        </configuration>
      </plugin>

      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-shade-plugin</artifactId>
        <version>2.3</version>
        <executions>
          <execution>
            <phase>package</phase>
            <goals>
              <goal>shade</goal>
            </goals>
            <configuration>
              <shadedArtifactAttached>true</shadedArtifactAttached>
              <shadedClassifierName>runnable</shadedClassifierName>
            </configuration>
          </execution>
        </executions>
      </plugin>

    </plugins>

After you build the Maven package, you'll get your regular my-app-1.0-SNAPSHOT.jar file and also a my-app-1.0-SNAPSHOT-runnable.jar. This is what you should run, with the command:

$ java -jar my-app-1.0-SNAPSHOT-runnable.jar

You can verify with this command:

$ jar tvf my-app-1.0-SNAPSHOT-runnable.jar

that the shaded jar contains the JCommander classes (and those of all the other Maven dependencies), while the regular one doesn't.