<dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-jdbc</artifactId> </dependency> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>1.1.1</version> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <version>1.18.2</version> <scope>provided</scope> </dependency> 

讯享网 # # MySQL配置 # 连接信息 spring.datasource.url = jdbc:mysql://localhost:3306/mydb 用户名 spring.datasource.username = root 密码 spring.datasource.password = admin123 驱动 spring.datasource.driver-class-name = com.mysql.cj.jdbc.Driver # # MyBatis配置 # po类存放目录 mybatis.type-aliases-package = com.leichuangkj.async.dao.po mapper(.xml)资源文件存放路径 mybatis.mapper-locations = classpath:mybatis/mapper/*.xml spring.aop.proxy-target-class = true 

@Data @NoArgsConstructor @AllArgsConstructor @ToString public class User { 
    private Integer id; private String name; private String email; } 

然后在dao目录下新建mapper目录，并在mapper目录下新建UserMapper接口，具体代码如下。

讯享网@Repository public interface UserMapper { 
    List<User> findAll(); } 

最后在resource目录下新建“mybatis/mapper”目录，并在mapper目录下新建UserMapper.xml文件，具体代码如下。

讯享网

<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" > <mapper namespace="com.leichuangkj.async.dao.mapper.UserMapper" > <resultMap id="BaseResultMap" type="com.leichuangkj.async.dao.po.User"> <constructor> <idArg column="id" javaType="java.lang.Integer" jdbcType="INTEGER" /> <arg column="name" javaType="java.lang.String" jdbcType="VARCHAR" /> <arg column="email" javaType="java.lang.String" jdbcType="VARCHAR" /> </constructor> </resultMap> <select id="findAll" resultMap="BaseResultMap"> select id, name, email from user </select> </mapper> 

讯享网public interface IUser { 
    List<User> findAllSync() ; Future<List<User>> findAllAsync(); } 

然后在service目录下新建impl目录，并在impl目录下新建UserImpl实现类，具体代码如下。

@Service public class UserImpl implements IUser { 
    @Autowired UserMapper userMapper; @Override public List<User> findAllSync() { 
    try { 
    System.out.println("开始做任务"); long start = System.currentTimeMillis(); List<User> userList = userMapper.findAll(); long end = System.currentTimeMillis(); System.out.println("完成任务，耗时:" + (end - start)+"毫秒"); return userList; }catch (Exception e){ 
    return Collections.emptyList(); } } @Async @Override public Future<List<User>> findAllAsync() { 
    try { 
    System.out.println("开始做任务"); long start = System.currentTimeMillis(); List<User> userList = userMapper.findAll(); long end = System.currentTimeMillis(); System.out.println("完成任务，耗时:" + (end - start)+"毫秒"); return new AsyncResult<>(userList); }catch (Exception e){ 
    return new AsyncResult<>(null); } } } 

讯享网@Controller @RequestMapping("/user") public class UserController { 
    @Autowired UserImpl userImpl; @RequestMapping(value = "/findAllSync",method = RequestMethod.GET) public void findAllSync(){ 
    long start = System.currentTimeMillis(); System.out.println("第一次查询所有用户"); List<User> userList1 = userImpl.findAllSync(); System.out.println("第二次查询所有用户"); List<User> userList2 = userImpl.findAllSync(); System.out.println("第三次查询所有用户"); List<User> userList3 = userImpl.findAllSync(); long end = System.currentTimeMillis(); System.out.println("总共消耗:"+ (end - start) + "毫秒"); } @RequestMapping(value = "/findAllAsync",method = RequestMethod.GET) public void findAllAsync() throws InterruptedException { 
    long start = System.currentTimeMillis(); System.out.println("第一次查询所有用户"); Future<List<User>> userList1 = userImpl.findAllAsync(); System.out.println("第二次查询所有用户"); Future<List<User>> userList2 = userImpl.findAllAsync(); System.out.println("第三次查询所有用户"); Future<List<User>> userList3 = userImpl.findAllAsync(); while(true){ 
    if(userList1.isDone()&&userList2.isDone()&&userList3.isDone()){ 
    break; }else{ 
    Thread.sleep(10); } } long end = System.currentTimeMillis(); System.out.println("总共消耗:"+ (end - start) + "毫秒"); } } 

@MapperScan(basePackages = "com.leichuangkj.async.dao.mapper") @SpringBootApplication @EnableAsync(proxyTargetClass = true) public class AsyncApplication { 
    public static void main(String[] args) { 
    SpringApplication.run(AsyncApplication.class, args); } } 

8.测试
启动项目，然后分别在postman中请求“http://localhost:8080/user/findAllSync”和“http://localhost:8080/user/findAllAsync”，可以在控制台看到相应的执行结果，测试结果如下图所示，可以看到同步执行三次查询耗时为988毫秒，异步执行三次查询耗时772毫秒，由此可见，异步调用速度比同步调用速度快。

9.工程目录结构