在IBM JRE上運行jMockit測試時出現AttachNotSupportedException

Question

當我嘗試使用IBM JDK運行簡單的jMockit/JUnit測試時，出現以下異常。有沒有人遇到過這個問題？我試着給出-Dcom.ibm.tools.attach.enable=yes作爲VM的參數，但沒有運氣。 Sun JDK中相同的代碼工作正常。

java.lang.RuntimeException: com.sun.tools.attach.AttachNotSupportedException: Unable to enqueue operation: the target VM does not support attach mechanism 
    at mockit.internal.startup.JDK6AgentLoader.getVirtualMachineImplementationFromEmbeddedOnes(JDK6AgentLoader.java:89) 
    at mockit.internal.startup.JDK6AgentLoader.loadAgent(JDK6AgentLoader.java:54) 
    at mockit.internal.startup.AgentInitialization.initializeAccordingToJDKVersion(AgentInitialization.java:21) 
    at mockit.internal.startup.Startup.initializeIfNeeded(Startup.java:98) 
    at mockit.internal.startup.Startup.initializeIfPossible(Startup.java:112) 
    at org.junit.runner.Runner.<clinit>(Runner.java:22) 
    at java.lang.J9VMInternals.initializeImpl(Native Method) 
    at java.lang.J9VMInternals.initialize(J9VMInternals.java:200) 
    at java.lang.J9VMInternals.initialize(J9VMInternals.java:167) 
    at java.lang.J9VMInternals.initialize(J9VMInternals.java:167) 
    at org.junit.internal.builders.JUnit4Builder.runnerForClass(JUnit4Builder.java:13) 
    at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:57) 
    at org.junit.internal.builders.AllDefaultPossibilitiesBuilder.runnerForClass(AllDefaultPossibilitiesBuilder.java:29) 
    at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:57) 
    at org.junit.internal.requests.ClassRequest.getRunner(ClassRequest.java:24) 
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.<init>(JUnit4TestReference.java:33) 
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestClassReference.<init>(JUnit4TestClassReference.java:25) 
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestLoader.createTest(JUnit4TestLoader.java:48) 
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestLoader.loadTests(JUnit4TestLoader.java:38) 
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:452) 
    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: com.sun.tools.attach.AttachNotSupportedException: Unable to enqueue operation: the target VM does not support attach mechanism 
    at sun.tools.attach.WindowsVirtualMachine.<init>(WindowsVirtualMachine.java:64) 
    at mockit.internal.startup.JDK6AgentLoader.getVirtualMachineImplementationFromEmbeddedOnes(JDK6AgentLoader.java:73) 
    ... 22 more 
java.lang.NoClassDefFoundError: org.junit.internal.runners.ErrorReportingRunner (initialization failure) 
    at java.lang.J9VMInternals.initialize(J9VMInternals.java:140) 
    at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:59) 
    at org.junit.internal.requests.ClassRequest.getRunner(ClassRequest.java:24) 
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.<init>(JUnit4TestReference.java:33) 
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestClassReference.<init>(JUnit4TestClassReference.java:25) 
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestLoader.createTest(JUnit4TestLoader.java:48) 
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestLoader.loadTests(JUnit4TestLoader.java:38) 
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:452) 
    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.NoClassDefFoundError: org.junit.runner.Runner (initialization failure) 
    at java.lang.J9VMInternals.initialize(J9VMInternals.java:140) 
    at java.lang.J9VMInternals.initialize(J9VMInternals.java:167) 
    at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:59) 
    at org.junit.internal.builders.AllDefaultPossibilitiesBuilder.runnerForClass(AllDefaultPossibilitiesBuilder.java:29) 
    at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:57) 
    ... 9 more 
Caused by: java.lang.RuntimeException: com.sun.tools.attach.AttachNotSupportedException: Unable to enqueue operation: the target VM does not support attach mechanism 
    at mockit.internal.startup.JDK6AgentLoader.getVirtualMachineImplementationFromEmbeddedOnes(JDK6AgentLoader.java:89) 
    at mockit.internal.startup.JDK6AgentLoader.loadAgent(JDK6AgentLoader.java:54) 
    at mockit.internal.startup.AgentInitialization.initializeAccordingToJDKVersion(AgentInitialization.java:21) 
    at mockit.internal.startup.Startup.initializeIfNeeded(Startup.java:98) 
    at mockit.internal.startup.Startup.initializeIfPossible(Startup.java:112) 
    at org.junit.runner.Runner.<clinit>(Runner.java:22) 
    at java.lang.J9VMInternals.initializeImpl(Native Method) 
    at java.lang.J9VMInternals.initialize(J9VMInternals.java:200) 
    at java.lang.J9VMInternals.initialize(J9VMInternals.java:167) 
    at java.lang.J9VMInternals.initialize(J9VMInternals.java:167) 
    at org.junit.internal.builders.JUnit4Builder.runnerForClass(JUnit4Builder.java:13) 
    at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:57) 
    ... 11 more 
Caused by: com.sun.tools.attach.AttachNotSupportedException: Unable to enqueue operation: the target VM does not support attach mechanism 
    at sun.tools.attach.WindowsVirtualMachine.<init>(WindowsVirtualMachine.java:64) 
    at mockit.internal.startup.JDK6AgentLoader.getVirtualMachineImplementationFromEmbeddedOnes(JDK6AgentLoader.java:73) 
    ... 22 more 

我試圖給VM參數-javaagent:jmockit.jar由凱文·韋爾克的建議，我得到了下面的異常。

Exception in thread "main" java.lang.reflect.InvocationTargetException 
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:48) 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:37) 
    at java.lang.reflect.Method.invoke(Method.java:600) 
    at sun.instrument.InstrumentationImpl.loadClassAndStartAgent(InstrumentationImpl.java:335) 
    at sun.instrument.InstrumentationImpl.loadClassAndCallPremain(InstrumentationImpl.java:350) 
Caused by: java.lang.NullPointerException 
    at mockit.internal.annotations.MockClassSetup.validateRealClass(MockClassSetup.java:59) 
    at mockit.internal.annotations.MockClassSetup.<init>(MockClassSetup.java:38) 
    at mockit.internal.annotations.MockClassSetup.<init>(MockClassSetup.java:77) 
    at mockit.internal.annotations.MockClassSetup.<init>(MockClassSetup.java:99) 
    at mockit.internal.startup.JMockitInitialization.setUpInternalStartupMock(JMockitInitialization.java:56) 
    at mockit.internal.startup.JMockitInitialization.initialize(JMockitInitialization.java:29) 
    at mockit.internal.startup.Startup.initialize(Startup.java:68) 
    at mockit.internal.startup.Startup.premain(Startup.java:56) 
    ... 6 more 

Fatal error: processing of -javaagent failed 

Answer 1

的附加API只需在IBM JDK 6.0不起作用，至少在Windows上。因此，有必要使用-javaagent:jmockit.jar參數。

發生在MockClassSetup.java:59（使用-javaagent）時發生的NullPointerException是由IBM JDK中的錯誤引起的。當在註釋屬性（本例中爲@MockClass）中引用的類型不在類路徑中時，JDK應該拋出TypeNotPresentException。 Oracle JDK按預期執行操作，但IBM JDK返回null而不是屬性值。

我剛在9月底之前在下一個JMockit版本中提供了類MockClassSetup的解決方法。現在，您可以通過將TestNG添加到類路徑中來避免此問題（因爲「未找到類型」是org.testng.TestNG類）。

Answer 2

某些版本的IBM JDK不能正確支持連接機制。您可以嘗試使用-javaagent：jmockit.jar參數運行。以下信息有點舊，但仍可能適用，因爲其他JDK不一定完全支持附加機制。

看到這個：http://code.google.com/p/jmockit/issues/detail?id=18

Answer 3

我也嘗試使用JMockit來覆蓋第三方庫中的類中的最終方法。我得到了上面討論的同樣的問題，並且再次添加VM arg -javaagent:C:/<Path-to-jar>/jmockit.jar只給了我一個不同類型的錯誤。我也在使用Websphere附帶的IBM JDK 6.0。這是一種遺憾，但它看起來像覆蓋最終方法是不可能的：我找不到任何其他可以做到的測試框架。

Answer 4

以上回答使用-javaagent是正確的。如果你正在使用maven這是一個有點棘手，所以這裏是我是如何做的：

1. 添加Maven的依賴，插件，這樣你就可以產生絕對路徑依賴：

<plugin> 
    <groupId>org.apache.maven.plugins</groupId> 
    <artifactId>maven-dependency-plugin</artifactId> 
    <version>2.5.1</version> 
    <executions> 
    <execution> 
     <id>getClasspathFilenames</id> 
     <goals> 
     <goal>properties</goal> 
     </goals> 
    </execution> 
    </executions> 
</plugin> 

2.添加-javaagent來保命插件

<plugin> 
    <groupId>org.apache.maven.plugins</groupId> 
    <artifactId>maven-surefire-plugin</artifactId> 
    <version>2.13</version> 
    <configuration> 
    <argLine>-javaagent:${com.googlecode.jmockit:jmockit:jar} -XX:-UseSplitVerifier</argLine> 
    </configuration> 
</plugin> 

3.還有，你沒有到，但我建議使用相對較新版本的jmockit。在1.1（之前的2012年9月通過修復@羅熱檢測到此問題，但無論加入-javaagent修復它作爲參考。我正在使用可用的最新版本的Maven中央（2.5）作爲此評論的：

<dependency> 
    <groupId>com.googlecode.jmockit</groupId> 
    <artifactId>jmockit</artifactId> 
    <!-- Use latest version. 1.1 gives AttachNotSupportedException --> 
    <version>1.5</version> 
    <scope>test</scope> 
</dependency> 

Answer 5

你只需要將JDK更新到1.8，我測試了這個版本的JDK，這個問題已經解決了。

Answer 6

爲javagent的萬無一失使用maven的設置是這樣的：

<plugin> 
    <groupId>org.apache.maven.plugins</groupId> 
    <artifactId>maven-surefire-plugin</artifactId> 
    <version>2.18.1</version> 
    <configuration> 
     .... 
     <argLine>-javaagent:"${settings.localRepository}"/org/jmockit/jmockit/1.11/jmockit-1.11.jar</argLine> 
    </configuration> 
    </plugin> 

上述假定您使用以下依賴性：

<dependency> 
    <groupId>org.jmockit</groupId> 
    <artifactId>jmockit</artifactId> 
    <version>1.11</version> 
    <scope>test</scope> 
    </dependency> 

如果您使用的是不同的版本，然後修改argLine值適當。

來源：http://jmockit.googlecode.com/svn-history/r1166/trunk/www/installation.html