Question

I am trying to write a unit test for a sonar plugin. However, on mocking its Project class, the test fails as Mockito tries to use a wrong classname.
my test code is:

import org.sonar.api.resources.Project;

Project project = mock(Project.class);

On running the unit test, either through maven or directly in eclipse, the following stacktrace comes up:

java.lang.NoClassDefFoundError: org/apache/maven/project/MavenProject
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Class.java:2427)
at java.lang.Class.getDeclaredMethods(Class.java:1791)
at org.mockito.cglib.core.ReflectUtils.addAllMethods(ReflectUtils.java:349)
at org.mockito.cglib.proxy.Enhancer.getMethods(Enhancer.java:422)
at org.mockito.cglib.proxy.Enhancer.generateClass(Enhancer.java:457)
at org.mockito.cglib.core.DefaultGeneratorStrategy.generate(DefaultGeneratorStrategy.java:25)
at org.mockito.cglib.core.AbstractClassGenerator.create(AbstractClassGenerator.java:217)
at org.mockito.cglib.proxy.Enhancer.createHelper(Enhancer.java:378)
at org.mockito.cglib.proxy.Enhancer.createClass(Enhancer.java:318)
at org.mockito.internal.creation.jmock.ClassImposterizer.createProxyClass(ClassImposterizer.java:93)
at org.mockito.internal.creation.jmock.ClassImposterizer.imposterise(ClassImposterizer.java:50)
at org.mockito.internal.util.MockUtil.createMock(MockUtil.java:54)
at org.mockito.internal.MockitoCore.mock(MockitoCore.java:45)
at org.mockito.Mockito.mock(Mockito.java:921)
at org.mockito.Mockito.mock(Mockito.java:816)
at com.databorough.sonar.xametric.MetricAnalysisSensorTest.shouldExecuteOnProjectWithAllParams(MetricAnalysisSensorTest.java:37)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28)
at org.junit.runners.BlockJUnit4ClassRunner.runNotIgnored(BlockJUnit4ClassRunner.java:79)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:71)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:49)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
at org.apache.maven.surefire.junit4.JUnit4Provider.execute(JUnit4Provider.java:252)
at org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:141)
at org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:112)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.maven.surefire.util.ReflectionUtils.invokeMethodWithArray(ReflectionUtils.java:189)
at org.apache.maven.surefire.booter.ProviderFactory$ProviderProxy.invoke(ProviderFactory.java:165)
at org.apache.maven.surefire.booter.ProviderFactory.invokeProvider(ProviderFactory.java:85)
at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:113)
at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:75)
Caused by: java.lang.ClassNotFoundException: org.apache.maven.project.MavenProject
    at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
    ... 47 more

The project is in the classpath as the plugin builds successfully.
How can I set the test runner/maven to treat Project as org.sonar.api.resources.Project class?

Answer 1

Your “Project” class is correctly treated as “org.sonar.api.resources.Project”.

The problem comes from the fact that Sonar internally uses “org.apache.maven.project.MavenProject”, so this class must be on your test classpath. Adding the following dependency to your POM will solve the issue:

<dependency>
  <groupId>org.apache.maven</groupId>
  <artifactId>maven-project</artifactId>
  <version>2.0.6</version>
  <scope>test</scope>
</dependency>