I'm writing unit test with JUnit and PowerMockito for classes in a Eclipse RCP application. If I run every test as stand-alone, everything works fine.
But when I group the test to a TestSuite, all tests fail with this error:
java.lang.UnsatisfiedLinkError: Could not load SWT library. Reasons:
no swt-win32-3836 in java.library.path
no swt-win32 in java.library.path
Native Library C:\Users\franzm\.swt\lib\win32\x86_64\swt-win32-3836.dll already loaded in another classloader
Can't load library: C:\Users\franzm\.swt\lib\win32\x86_64\swt-win32.dll
at org.eclipse.swt.internal.Library.loadLibrary(Library.java:331)
at org.eclipse.swt.internal.Library.loadLibrary(Library.java:240)
at org.eclipse.swt.internal.C.<clinit>(C.java:21)
at org.eclipse.swt.widgets.Widget.<clinit>(Widget.java:103)
at com.example.app.client.ui.filters.FilterDtoUtil.formatDateFormat(FilterDtoUtil.java:325)
at com.example.app.client.ui.filters.FilterDtoUtil.getMarketVariantsProductionSitesWithDates(FilterDtoUtil.java:358)
at com.example.app.client.ui.filters.factories.FilterContributor.getFilterRow(FilterContributor.java:566)
at com.example.app.client.ui.filters.factories.AbstractBigFilterFactory.getFilterRow(AbstractBigFilterFactory.java:59)
at com.example.app.client.ui.excelexport.AbstractExcelTest.before(AbstractExcelTest.java:73)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.junit.internal.runners.MethodRoadie.runBefores(MethodRoadie.java:132)
at org.junit.internal.runners.MethodRoadie.runBeforesThenTestThenAfters(MethodRoadie.java:95)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.executeTest(PowerMockJUnit44RunnerDelegateImpl.java:294)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTestInSuper(PowerMockJUnit47RunnerDelegateImpl.java:127)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTest(PowerMockJUnit47RunnerDelegateImpl.java:82)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.runBeforesThenTestThenAfters(PowerMockJUnit44RunnerDelegateImpl.java:282)
at org.junit.internal.runners.MethodRoadie.runTest(MethodRoadie.java:86)
at org.junit.internal.runners.MethodRoadie.run(MethodRoadie.java:49)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.invokeTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:207)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.runMethods(PowerMockJUnit44RunnerDelegateImpl.java:146)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$1.run(PowerMockJUnit44RunnerDelegateImpl.java:120)
at org.junit.internal.runners.ClassRoadie.runUnprotected(ClassRoadie.java:33)
at org.junit.internal.runners.ClassRoadie.runProtected(ClassRoadie.java:45)
at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.run(PowerMockJUnit44RunnerDelegateImpl.java:118)
at org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run(JUnit4TestSuiteChunkerImpl.java:104)
at org.powermock.modules.junit4.common.internal.impl.AbstractCommonPowerMockRunner.run(AbstractCommonPowerMockRunner.java:53)
at org.powermock.modules.junit4.PowerMockRunner.run(PowerMockRunner.java:53)
at org.junit.runners.Suite.runChild(Suite.java:127)
at org.junit.runners.Suite.runChild(Suite.java:26)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
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)
Ok, I get that the problem is that the DLL is already loaded. But how can I get around this? We have an answer at stack overflow (when use junit4 + powermock to execute all test suites , I got an error : swt-win32-3650.dll already loaded in another classloader) but this does not help me at all. Finding all classes which may use SWT is to much work for the gained result.
Isn't there any better solution?
(Edit: I use PowerMockito to mock a static class)