Maven JUnit Test Case NoClassDefFoundException on Test class

Question

I have a parameterized test case, just like a bunch of other test cases I have in the testing suite, that I have been trying to add the them.

package com.example;

import com.google.gson.Gson;
import com.example.Event;
import com.example.LocalStorage;
import com.example.TimeMachine;

import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameters;

import java.util.Arrays;
import java.util.Collection;

import static org.fest.assertions.api.Assertions.assertThat;
import static org.mockito.Mockito.mock;

@RunWith(Parameterized.class)
public class TimeMachineEventEndTimeTest {

    public TimeMachineEventEndTimeTest(Event event, String end_time) {
        _event = event;
        _end_time = end_time;
    }

    @Parameters
    public static Collection<Object[]> data() {
        return Arrays.asList(new Object[][]{
            { _UNSCHEDULED, "" },
            { _NOON_FOR_1_HOUR, "13:00" },
            { _NOON_FOR_HALF_HOUR, "12:30" },
            { _MIDNIGHT_FOR_1_HOUR, "1:00" },
            { _MIDNIGHT_FOR_HALF_HOUR, "0:30" },
            { _MIDNIGHT_FOR_12_HOUR, "12:00" }
        });
    }

    @Before
    public void initialize() throws Exception {
        _time_machine = new _TimeMachine();
    }

    @Test
    public void testEndTimeForEvent() throws Exception {
        assertThat(_time_machine.endTimeForEvent(_event)).isEqualTo(_end_time);
    }

    private TimeMachine _time_machine;
    private final Event _event;
    private final String _end_time;
    private static final Gson _gson = new _GsonProvider(mock(LocalStorage.class)).gson();
    private static final Event _UNSCHEDULED = _gson.fromJson("{}", Event.class);
    private static final Event _NOON_FOR_1_HOUR = _gson.fromJson("{\n" +
        "      \"starttime\" : \"12:00\",\n" +
        "      \"duration\" : \"60\",\n" +
        "    }", Event.class);
    private static final Event _NOON_FOR_HALF_HOUR = _gson.fromJson("{\n" +
        "      \"starttime\" : \"12:00\",\n" +
        "      \"duration\" : \"30\",\n" +
        "    }", Event.class);
    private static final Event _MIDNIGHT_FOR_1_HOUR = _gson.fromJson("{\n" +
        "      \"starttime\" : \"0:00\",\n" +
        "      \"duration\" : \"60\",\n" +
        "    }", Event.class);
    private static final Event _MIDNIGHT_FOR_HALF_HOUR = _gson.fromJson("{\n" +
        "      \"starttime\" : \"0:00\",\n" +
        "      \"duration\" : \"30\",\n" +
        "    }", Event.class);
    private static final Event _MIDNIGHT_FOR_12_HOUR = _gson.fromJson("{\n" +
        "      \"starttime\" : \"0:00\",\n" +
        "      \"duration\" : \"360\",\n" +
        "    }", Event.class);
}

I have a few test cases with nearly identical structure that test different methods in the same directory and package. All my other tests run and pass 100% except this test case throws the this stack trace:

java.lang.NoClassDefFoundError: Could not initialize class com.example.TimeMachineEventEndTimeTest at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:186) at org.apache.maven.surefire.report.SmartStackTraceParser.getClass(SmartStackTraceParser.java:63) at org.apache.maven.surefire.report.SmartStackTraceParser.(SmartStackTraceParser.java:53) at org.apache.maven.surefire.common.junit4.JUnit4StackTraceWriter.smartTrimmedStackTrace(JUnit4StackTraceWriter.java:72) at org.apache.maven.surefire.booter.ForkingRunListener.encode(ForkingRunListener.java:328) at org.apache.maven.surefire.booter.ForkingRunListener.encode(ForkingRunListener.java:312) at org.apache.maven.surefire.booter.ForkingRunListener.toString(ForkingRunListener.java:258) at org.apache.maven.surefire.booter.ForkingRunListener.testError(ForkingRunListener.java:131) at org.apache.maven.surefire.common.junit4.JUnit4RunListener.testFailure(JUnit4RunListener.java:111) at org.junit.runner.notification.RunNotifier$4.notifyListener(RunNotifier.java:100) at org.junit.runner.notification.RunNotifier$SafeNotifier.run(RunNotifier.java:41) at org.junit.runner.notification.RunNotifier.fireTestFailure(RunNotifier.java:97) at org.junit.internal.runners.ErrorReportingRunner.runCause(ErrorReportingRunner.java:57) at org.junit.internal.runners.ErrorReportingRunner.run(ErrorReportingRunner.java:34) at org.apache.maven.surefire.junit4.JUnit4Provider.execute(JUnit4Provider.java:264) at org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:153) at org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:124)

Answer 1

If anyone else runs into a similar problem, it seems that for me it was my last few lines where I create some Events. They had a small error in the JSON, which must cause Gson to error when constructing them.

 private static final Event _NOON_FOR_1_HOUR = _gson.fromJson("{\n" +
    "      \"starttime\" : \"12:00\",\n" +
    "      \"duration\" : \"60\"\n" +
    "    }", Event.class);
private static final Event _NOON_FOR_HALF_HOUR = _gson.fromJson("{\n" +
    "      \"starttime\" : \"12:00\",\n" +
    "      \"duration\" : \"30\"\n" +
    "    }", Event.class);
private static final Event _MIDNIGHT_FOR_1_HOUR = _gson.fromJson("{\n" +
    "      \"starttime\" : \"0:00\",\n" +
    "      \"duration\" : \"60\"\n" +
    "    }", Event.class);
private static final Event _MIDNIGHT_FOR_HALF_HOUR = _gson.fromJson("{\n" +
    "      \"starttime\" : \"0:00\",\n" +
    "      \"duration\" : \"30\"\n" +
    "    }", Event.class);
private static final Event _MIDNIGHT_FOR_12_HOUR = _gson.fromJson("{\n" +
    "      \"starttime\" : \"0:00\",\n" +
    "      \"duration\" : \"360\"\n" +
    "    }", Event.class);

The correction was to remove the "," after the "duration" values. It seems that the stacktrace was extremely cryptic and pretty misleading, indeed.

Answer 2

Could you run the test from your IDE? It looks like the stacktrace is misleading because of https://jira.codehaus.org/browse/SUREFIRE-962

It would be helpful, if you could provide a runnable gist, which reproduces the problem.