Spring Boot 2.2.0 无法使用@RunWith 使用JUnit4

使用IDEA创建Spring Initializr初始化带有web的Spring Boot 2.2.0版本的pom文件如下：

	<parent>
        <groupId>org.springframework.bootgroupId>
        <artifactId>spring-boot-starter-parentartifactId>
        <version>2.2.0.RELEASEversion>
        <relativePath/> 
    parent>
    
	<groupId>com.examplegroupId>
    	<artifactId>demoartifactId>
    	<version>0.0.1-SNAPSHOTversion>
    	<name>demoname>
    <description>Demo project for Spring Bootdescription>

    <properties>
        <java.version>1.8java.version>
    properties>

	<dependencies>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-webartifactId>
        dependency>

        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-testartifactId>
            <scope>testscope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintagegroupId>
                    <artifactId>junit-vintage-engineartifactId>
                exclusion>
            exclusions>
        dependency>
      dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.bootgroupId>
                <artifactId>spring-boot-maven-pluginartifactId>
                <configuration>
                    <fork>truefork>
                configuration>
            plugin>
        plugins>
    build>

此时默认的是JUnit5，网上很多Spring Boot2.X教程使用的是Junit4

只要把spring-boot-starter-test中的exclusions删除就好了

即

		<dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-testartifactId>
            <scope>testscope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintagegroupId>
                    <artifactId>junit-vintage-engineartifactId>
                exclusion>
            exclusions>
        dependency>

改成

		<dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-testartifactId>
            <scope>testscope>
        dependency>

原因：

查看源码，原来的依赖里排除了junit-vintage-engine依赖，而junit-vintage-engine依赖中包含4.12版的junit。@RunWith标签是在org.junit.runner包内。