1. 前提条件

开发环境已正确配置
工程已解决JUnit依赖关系（pom.xml）
我用的是4.12版本：

<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
</dependency></pre>

2. IDEA中JUnit配置

（1）打开Settings窗口搜索junit，如图（两个插件都勾选添加）：

image

（2） JUnitGenerator V2.0插件，可以帮助我们自动生成测试代码。如果搜索junit没有JUnitGenerator V2.0时，如下图操作（下载添加）：

image

更改生成文件目录步骤

打开File->Settings
搜索junit，找到JUnit Generator
修改Properties中Output Path为测试用例生成的目录，这里修改为java目录：
${SOURCEPATH}/../../test/java/${PACKAGE}/${FILENAME}

切换到JUnit 4选项卡，可以修改生成测试用例的模板，比如类名、包名

剩下几个配置的更改：

这里把Junit4那一栏的所有配置都拉出来了，如果下次要配置的话，粘贴好了。
具体修改的地方：
包名、import引入、@注解

######################################################################################## 
## 
## Available variables: 
##         $entryList.methodList - List of method composites 
##         $entryList.privateMethodList - List of private method composites 
##         $entryList.fieldList - ArrayList of class scope field names 
##         $entryList.className - class name 
##         $entryList.packageName - package name 
##         $today - Todays date in MM/dd/yyyy format 
## 
##            MethodComposite variables: 
##                $method.name - Method Name 
##                $method.signature - Full method signature in String form 
##                $method.reflectionCode - list of strings representing commented out reflection code to access method (Private Methods) 
##                $method.paramNames - List of Strings representing the method's parameters' names 
##                $method.paramClasses - List of Strings representing the method's parameters' classes 
## 
## You can configure the output class name using "testClass" variable below. 
## Here are some examples: 
## Test${entry.ClassName} - will produce TestSomeClass 
## ${entry.className}Test - will produce SomeClassTest 
## 
######################################################################################## 
## 
#macro (cap $strIn)$strIn.valueOf($strIn.charAt(0)).toUpperCase()$strIn.substring(1)#end 
## Iterate through the list and generate testcase for every entry. 
#foreach ($entry in $entryList) 
#set( $testClass="${entry.className}Test") 
## 
package $entry.packageName; 

import org.junit.Test; 
import org.junit.Before; 
import org.junit.After; 
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

/** 
* ${entry.className} Tester. 
* 
* @author <Authors name> 
* @since <pre>$today</pre> 
* @version 1.0 
*/ 

@Runwith(SpringRunner.class)
@SpringbootTest
public class $testClass { 

@Before
public void before() throws Exception { 
} 

@After
public void after() throws Exception { 
} 

#foreach($method in $entry.methodList) 
/** 
* 
* Method: $method.signature 
* 
*/ 
@Test
public void test#cap(${method.name})() throws Exception { 
//TODO: Test goes here... 
} 

#end 

#foreach($method in $entry.privateMethodList) 
/** 
* 
* Method: $method.signature 
* 
*/ 
@Test
public void test#cap(${method.name})() throws Exception { 
//TODO: Test goes here... 
#foreach($string in $method.reflectionCode) 
$string 
#end 
} 

#end 
} 
#end