注释类型 RunWith

@Retention(RUNTIME)
@Target(TYPE)
@Inherited
public @interface RunWith

When a class is annotated with @RunWith or extends a class annotated with @RunWith, JUnit will invoke the class it references to run the tests in that class instead of the runner built into JUnit. We added this feature late in development. While it seems powerful we expect the runner API to change as we learn how people really use it. Some of the classes that are currently internal will likely be refined and become public. For example, suites in JUnit 4 are built using RunWith, and a custom runner named Suite:

 @RunWith(Suite.class)
 @SuiteClasses({ATest.class, BTest.class, CTest.class})
 public class ABCSuite {
 }