以下是一个基于Spring Boot的简单Java Web入门案例的步骤和代码示例：
- 创建Maven项目并添加依赖：
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>2.1.4</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
- 配置application.properties：
spring.datasource.url=jdbc:mysql://localhost:3306/your_database?useSSL=false
spring.datasource.username=root
spring.datasource.password=yourpassword
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
mybatis.mapper-locations=classpath:mapper/*.xml
mybatis.type-aliases-package=com.yourpackage.model
- 创建实体类和Mapper接口：
// 实体类 User.java
public class User {
private Integer id;
private String name;
// getters and setters
}
// Mapper 接口 UserMapper.java
@Mapper
public interface UserMapper {
User selectUserById(Integer id);
}
- 创建Service和Controller：
// Service 类 UserService.java
@Service
public class UserService {
@Autowired
private UserMapper userMapper;
public User getUserById(Integer id) {
return userMapper.selectUserById(id);
}
}
// Controller 类 UserController.java
@RestController
@RequestMapping("/users")
public class UserController {
@Autowired
private UserService userService;
@GetMapping("/{id}")
public User getUser(@PathVariable Integer id) {
return userService.getUserById(id);
}
}
- 创建启动类：
@SpringBootApplication
public class DemoApplication {
public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
}
}
- 使用Postman或浏览器测试API：
GET http://localhost:8080/users/1
以上代码提供了一个简单的Java Web入门案例，包括了Maven项目管理、Spring Boot的使用、MyBatis的集成以及对MySQL的连接。通过这个案例，开发者可以学习如何构建一个基础的Web应用，并且熟悉如何使用Spring Boot进行Web开发。