java报错java.lang.NoSuchMethodError

 最近在写一个客户管理系统，用Test测试mapper的时候报了java.lang.NoSuchMethodError的错误。

java.lang.NoSuchMethodError: org.springframework.util.Assert.notNull(Ljava/lang/Object;Ljava/util/function/Supplier;)V
	at org.springframework.test.context.support.ContextLoaderUtils.resolveContextConfigurationAttributes(ContextLoaderUtils.java:240)
	at org.springframework.test.context.support.AbstractTestContextBootstrapper.buildMergedContextConfiguration(AbstractTestContextBootstrapper.java:295)
	at org.springframework.test.context.support.AbstractTestContextBootstrapper.buildTestContext(AbstractTestContextBootstrapper.java:108)
	at org.springframework.test.context.TestContextManager.<init>(TestContextManager.java:139)
	at org.springframework.test.context.TestContextManager.<init>(TestContextManager.java:124)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTestContextManager(SpringJUnit4ClassRunner.java:151)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.<init>(SpringJUnit4ClassRunner.java:142)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
	at java.lang.reflect.Constructor.newInstance(Unknown Source)
	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.eclipse.jdt.internal.junit4.runner.JUnit4TestLoader.createUnfilteredTest(JUnit4TestLoader.java:84)
	at org.eclipse.jdt.internal.junit4.runner.JUnit4TestLoader.createTest(JUnit4TestLoader.java:70)
	at org.eclipse.jdt.internal.junit4.runner.JUnit4TestLoader.loadTests(JUnit4TestLoader.java:43)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:444)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:678)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192)

 下面这个是我的Test类：

package com.atguigu.crud.test;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import com.atguigu.crud.bean.Department;
import com.atguigu.crud.dao.DepartmentMapper;

import org.junit.Test;
import org.junit.runner.RunWith;

/*
 * 推荐Spring的项目就可以使用Spring的单元测试，可以自动注入我们需要的组件
 * 导入springTest模块
 * @ContextConfiguration指定spring的配置文件位置
 */
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations={"classpth:ApplicationContext.xml"})
public class MapprtTest {
	
	@Autowired
	DepartmentMapper departmentMapper;
	
	/*
	 * 测试DepartmentMapper
	 */
	@Test
	public void testCRUD(){
//		//1.创建springIOC容器
//		ApplicationContext ioc = new ClassPathXmlApplicationContext();
//		//2.从容器中获取mapper
//		ioc.getBean(DepartmentMapper.class);
		System.out.println(departmentMapper);
		
		//1.插入几个部门
		departmentMapper.insertSelective(new Department(1,"开发部"));
		departmentMapper.insertSelective(new Department(2,"测试部"));
	}
	
}

 百度了很多网上的资料，普遍的错误都是

1.jar包冲突

2.重启eclipse

3.找不到该方法

4.没写@Test

5.没导入hamcrest.jar

但是，以上的五个问题我都没发生过，后来问了我同学，才知道是哪里错误。

把@RunWith(SpringJUnit4ClassRunner.class)给注释掉，就不会报错了。

 运行正常