Spring Boot入门案例

• 原生开发SpringMVC程序过程

<dependencies>
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
        <version>3.1.0</version>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>5.2.10.RELEASE</version>
    </dependency>
</dependencies>

public class ServletConfig extends AbstractAnnotationConfigDispatcherServletInitializer {
    protected Class<?>[] getRootConfigclasses() {
        return new Class[]{SpringConfig.class};
    }

    protected Class<?>[] getServletConfigClasses() {
        return new Class[]{SpringMvcConfig.class};
    }

    protected String[] getServletMappings() {
        return new String[]{"/"};
    }
}

@Configuration
@ComponentScan("com.xxx.controller")
@EnableWebMvc
public class SpringMvcConfig {

}

@RestController
@RequestMapping("/books")
public class BookController {

    @Autowired
    private BookService bookService;

    @GetMapping("/{id}")
    public Result getById(@PathVariable Integer id) {
        Book book = bookService.getById(id);
        Integer code = book != null ? Code.GET_OK : Code.GET_ERR;
        String msg = book != null ? "数据查询失败，请重试！";
        return new Result(code, book, msg);
    }
}

• 创建Boot项目

Project Structure --> New Module --> Spring Initializr --> 填写信息 --> 勾选（Spring Web）--> Finish 删除除 pom.xml、src/ 以外的文件

BookController.java

@RestController
@RequestMapping("/books")
public class BookController {

    @GetMapping("/{id}")
    public String getById(@PathVariable Integer id) {
        System.out.println("id ==> "+id);
        return "hello, spring boot!";
    }
}