使用 jmock 时出现未知的类加载器错误？答案

【问题标题】：Unknown classloader error occurs when using jmock?使用 jmock 时出现未知的类加载器错误？
【发布时间】：2018-09-30 01:16:54
【问题描述】：

我将 jmock 1.37 与 jdk1.7 一起使用，但出现了如下所示的异常。我认为类加载器应该从 jmock.jar 加载 AttachProvider 类，但它从 jdk1.8 的 tools.jar 加载了同名的类。

为什么会这样？

java.lang.UnsupportedClassVersionError: com/sun/tools/attach/spi/AttachProvider : Unsupported major.minor version 52.0

at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:800)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:449)
at java.net.URLClassLoader.access$100(URLClassLoader.java:71)
at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
at mockit.internal.startup.Startup.initializeIfPossible(Startup.java:147)
at mockit.integration.junit4.JMockit.<clinit>(JMockit.java:21)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
at org.junit.internal.builders.AnnotatedBuilder.buildRunner(AnnotatedBuilder.java:104)
at org.junit.internal.builders.AnnotatedBuilder.runnerForClass(AnnotatedBuilder.java:86)
at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:59)
at org.junit.internal.builders.AllDefaultPossibilitiesBuilder.runnerForClass(AllDefaultPossibilitiesBuilder.java:26)
at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:59)
at org.junit.internal.requests.ClassRequest.getRunner(ClassRequest.java:33)
at org.junit.internal.requests.FilterRequest.getRunner(FilterRequest.java:36)
at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:49)
at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:51)
at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)

【问题讨论】：

标签： java classloader jmock

【解决方案1】：

从上面显示的错误来看，您似乎正在执行为 JDK 8 编译的类。JDK 1.7 将不支持该代码（请参阅answer）。

您似乎也在 IntelliJ 中运行测试。也许您需要setup the project JDK 到 1.7 版？

【讨论】：