关于junit 报空指针异常

1.junit没有build path

2.junit的版本有问题，就是说你该换一个junit

3.Android开发时把Android junit当做java junit使用了，如果你没有安装Android开发环境，就是你不是搞Android开发的，就是1.2的问题

4.如果前三种没解决问题，这里还有个通用的看日志。查看WorkSpace下的.metadata文件夹下的.log文件，看一下是否存在问题。这里的日志情况我贴一下

!ENTRY org.python.pydev.shared_core 4 4 2018-07-12 13:49:51.445
!MESSAGE No message gotten (null message).
!STACK 0
java.lang.NullPointerException
	at org.python.pydev.debug.ui.launching.PythonRunnerConfig.getWorkingDirectory(PythonRunnerConfig.java:210)
	at org.python.pydev.debug.ui.PythonConsoleLineTracker.initLaunchConfiguration(PythonConsoleLineTracker.java:160)
	at org.python.pydev.debug.ui.PythonConsoleLineTracker.init(PythonConsoleLineTracker.java:131)
	at org.eclipse.debug.internal.ui.views.console.ConsoleLineNotifier.connect(ConsoleLineNotifier.java:56)
	at org.eclipse.ui.internal.console.ConsolePatternMatcher.addPatternMatchListener(ConsolePatternMatcher.java:234)
	at org.eclipse.ui.console.TextConsole.addPatternMatchListener(TextConsole.java:409)
	at org.eclipse.debug.internal.ui.views.console.ProcessConsole.<init>(ProcessConsole.java:228)
	at org.eclipse.debug.internal.ui.views.console.ProcessConsoleManager.launchChanged(ProcessConsoleManager.java:149)
	at org.eclipse.debug.internal.core.LaunchManager$LaunchNotifier.run(LaunchManager.java:453)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
	at org.eclipse.debug.internal.core.LaunchManager$LaunchNotifier.notify(LaunchManager.java:433)
	at org.eclipse.debug.internal.core.LaunchManager.fireUpdate(LaunchManager.java:1043)
	at org.eclipse.debug.core.Launch.fireChanged(Launch.java:466)
	at org.eclipse.debug.core.Launch.addProcess(Launch.java:420)
	at org.eclipse.debug.core.model.RuntimeProcess.<init>(RuntimeProcess.java:126)
	at org.eclipse.debug.core.DebugPlugin.newProcess(DebugPlugin.java:791)
	at org.eclipse.jdt.launching.AbstractVMRunner.newProcess(AbstractVMRunner.java:175)
	at org.eclipse.jdt.internal.launching.StandardVMRunner.run(StandardVMRunner.java:438)
	at org.eclipse.jdt.junit.launcher.JUnitLaunchConfigurationDelegate.launch(JUnitLaunchConfigurationDelegate.java:204)
	at org.eclipse.debug.internal.core.LaunchConfiguration.launch(LaunchConfiguration.java:885)
	at org.eclipse.debug.internal.core.LaunchConfiguration.launch(LaunchConfiguration.java:739)
	at org.eclipse.debug.internal.ui.DebugUIPlugin.buildAndLaunch(DebugUIPlugin.java:1039)
	at org.eclipse.debug.internal.ui.DebugUIPlugin$8.run(DebugUIPlugin.java:1256)
	at org.eclipse.core.internal.jobs.Worker.run(Worker.java:56)

!ENTRY org.eclipse.jdt.junit.core 4 4 2018-07-12 13:50:20.011

看到这里就是junit包出问题了，也就是说出的 问题是2.吧junit jar包版本换一下，问题解决。