java.lang.RuntimeException: Exception during suite construction

java.lang.RuntimeException: Exception during suite construction

使用Android studio1.1版，进行单元测试，发生了异常，如下：

Running tests

Test running started java.lang.RuntimeException: Exception during suite construction at android.test.suitebuilder.TestSuiteBuilder$FailedToCreateTests.testSuiteConstructionFailed(TestSuiteBuilder.java:238) at java.lang.reflect.Method.invokeNative(Native Method) at android.test.AndroidTestRunner.runTest(AndroidTestRunner.java:190) at android.test.AndroidTestRunner.runTest(AndroidTestRunner.java:175) at android.test.InstrumentationTestRunner.onStart(InstrumentationTestRunner.java:555) at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:1732) Caused by: java.lang.NullPointerException at android.test.suitebuilder.TestMethod.<init>(TestMethod.java:47) at android.test.suitebuilder.TestSuiteBuilder.build(TestSuiteBuilder.java:189) at android.test.InstrumentationTestRunner.onCreate(InstrumentationTestRunner.java:379) at android.app.ActivityThread.handleBindApplication(ActivityThread.java:4631) at android.app.ActivityThread.access$1300(ActivityThread.java:165) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1433) at android.os.Handler.dispatchMessage(Handler.java:107) at android.os.Looper.loop(Looper.java:194) at android.app.ActivityThread.main(ActivityThread.java:5391) at java.lang.reflect.Method.invokeNative(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:833) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:600) at dalvik.system.NativeStart.main(Native Method)

Finish

解决办法：最后发现，必须是无参构造方法

public MyFirstTestActivityTest(Class activityClass) {         super(activityClass); //不能用编辑器自动生成的参数(会报空指针异常)，只能自己传对象，如MainActivity.class     }