testNG与Spring集合别忘了@ContextConfiguration

1、使用testNG测试，简单使用只需要在pom文件里引入jar包，如下

<dependency>
            <groupId>org.testng</groupId>
            <artifactId>testng</artifactId>
            <scope>test</scope>
            <version>6.8.7</version>
  </dependency>

使用时，在测试方法上@Test即可（这里注意查看是import的testNG的还是junit的），如下

 public class ATest  {
	@Test
    public void test(){}
}

2、与Spring集合，为了更好的使用bean或其它配置
测试class需要继承AbstractTestNGSpringContextTests，并且一定不要忘记了加注解ContextConfiguration，否则就出现下面的错误了

java.lang.IllegalStateException: Failed to load ApplicationContext

	at org.springframework.test.context.CacheAwareContextLoaderDelegate.loadContext(CacheAwareContextLoaderDelegate.java:99)
	at org.springframework.test.context.TestContext.getApplicationContext(TestContext.java:122)
	at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:109)
	at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:75)
	at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:321)
	at org.springframework.test.context.testng.AbstractTestNGSpringContextTests.springTestContextPrepareTestInstance(AbstractTestNGSpringContextTests.java:145)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:84)
	at org.testng.internal.Invoker.invokeConfigurationMethod(Invoker.java:564)
	at org.testng.internal.Invoker.invokeConfigurations(Invoker.java:213)
	at org.testng.internal.Invoker.invokeConfigurations(Invoker.java:138)
	at org.testng.internal.TestMethodWorker.invokeBeforeClassMethods(TestMethodWorker.java:175)
	at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:107)
	at org.testng.TestRunner.privateRun(TestRunner.java:767)
	at org.testng.TestRunner.run(TestRunner.java:617)
	at org.testng.SuiteRunner.runTest(SuiteRunner.java:348)
	at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:343)
	at org.testng.SuiteRunner.privateRun(SuiteRunner.java:305)
	at org.testng.SuiteRunner.run(SuiteRunner.java:254)
	at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:52)
	at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:86)
	at org.testng.TestNG.runSuitesSequentially(TestNG.java:1224)
	at org.testng.TestNG.runSuitesLocally(TestNG.java:1149)
	at org.testng.TestNG.run(TestNG.java:1057)
	at org.testng.IDEARemoteTestNG.run(IDEARemoteTestNG.java:72)
	at org.testng.RemoteTestNGStarter.main(RemoteTestNGStarter.java:123)
Caused by: java.lang.IllegalArgumentException: Cannot load an ApplicationContext with a NULL 'contextLoader'. Consider annotating your test class with @ContextConfiguration or @ContextHierarchy.
	at org.springframework.util.Assert.notNull(Assert.java:112)
	at org.springframework.test.context.CacheAwareContextLoaderDelegate.loadContextInternal(CacheAwareContextLoaderDelegate.java:57)
	at org.springframework.test.context.CacheAwareContextLoaderDelegate.loadContext(CacheAwareContextLoaderDelegate.java:91)
	... 28 more

正确姿势是：

@ContextConfiguration(locations = { "classpath*:http-test.xml" })
public class ATest extends AbstractTestNGSpringContextTests {
	@Test
    public void test(){}
}

这里http-test.xml是自己设的Spring配置文件，如果不设置，则默认从classpath目录下读取applicationContext.xml