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javaandroidunit-testingjunit

Android Unit Test throws NoClassDefFoundError on Log


I get a java.lang.NoClassDefFoundError: android/util/Log error when I try to run my unit test project in eclipse.

Distilled down, my test code looks like this:

package com.randomtype.yycparking;

import junit.framework.TestCase;
import android.util.Log;

public class StallTests extends TestCase {  
    public void setUp() {
        Log.v("HI", "Fail");
    }

    public void testShouldParseIdFromTitle() {
        assertTrue(true);
    }
}

And the code throws an exception on the Log.v call. When I run the android project normally I don't get any exceptions around Log.

Full Stack Trace:

java.lang.NoClassDefFoundError: android/util/Log
    at com.randomtype.yycparking.StallTests.setUp(StallTests.java:11)
    at junit.framework.TestCase.runBare(TestCase.java:132)
    at junit.framework.TestResult$1.protect(TestResult.java:110)
    at junit.framework.TestResult.runProtected(TestResult.java:128)
    at junit.framework.TestResult.run(TestResult.java:113)
    at junit.framework.TestCase.run(TestCase.java:124)
    at junit.framework.TestSuite.runTest(TestSuite.java:243)
    at junit.framework.TestSuite.run(TestSuite.java:238)
    at org.eclipse.jdt.internal.junit.runner.junit3.JUnit3TestReference.run(JUnit3TestReference.java:130)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
Caused by: java.lang.ClassNotFoundException: android.util.Log
    at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
    ... 14 more

As pointed out by dtmilano, I wasn't running the unit tests as an Android JUnit Test. How can you tell the difference? Look for the little a like in the picture below:

Screen shot of a beside JUnit icon
(source: skitch.com)


Solution

  • Your tests should be in a separate Android Test Project (Project -> Android Tools -> New Android Project) and you should run them as Android JUnit Test (Run as -> Android JUnit Test).