SpringMVC

1、SpringMVC相关

SpringMVC与Servlet技术功能等同，加载表现层bean

表现层

@Controller:设定SpringMVC的核心控制器bean
@RequestMapping（“/”）：设置当前控制器方法请求访问路径，属性：value，指请求访问路径
@ResponseBody：设置当前控制器方法响应内容为当前返回值，无需解析
@RequestParam：绑定请求参数与处理器方法形参间的关系。用于接收url地址传参
@RequestBody：将外部传递的json数组数据映射到形参的集合对象中作为数据。用于接收json数据
@DateTimeFormat（pattern = “yyyy-MM-dd”）Data date

@Controller
@RequestMapping("/user")
public class UserController {

    @RequestMapping("/save")
    @ResponseBody
    public String save(){
        System.out.println("user save ...");
        return "{'module':'user save'}";
    }
    
    @RequestMapping("/delete")
    @ResponseBody
    public String save(){
        System.out.println("user delete ...");
        return "{'module':'user delete'}";
    }
}

配置类

//3.定义配置类加载Controller对应的bean
@Configuration
@ComponentScan("com.xxxx.controller")
@EnableWebMvc//开启json数据类型自动转换
public class SpringMvcConfig {
}

public class ServletContainersInitConfig extends AbstractAnnotationConfigDispatcherServletInitializer {

    protected Class<?>[] getServletConfigClasses() {
        return new Class[]{SpringMvcConfig.class};
    }
    protected String[] getServletMappings() {
        return new String[]{"/"};
    }
    protected Class<?>[] getRootConfigClasses() {
        return new Class[0];
    }
    //乱码处理
    @Override
    protected Filter[] getServletFilters() {
        CharacterEncodingFilter filter = new CharacterEncodingFilter();
        filter.setEncoding("UTF-8");
        return new Filter[]{filter};
    }
}

2、REST

按照REST风格访问资源时使用行为动作区分对资源进行了何种操作

• http://localhost/users 查询全部用户信息 GET（查询）
• http://localhost/users/1 查询指定用户信息 GET（查询）
• http://localhost/users 添加用户信息 POST（新增/保存）
• http://localhost/users 修改用户信息 PUT（修改/更新）
• http://localhost/users/1 删除用户信息 DELETE（删除）

@PathVariable：绑定路径参数与处理器方法形参间的关系，要求路径参数名与形参名一一对应。

表现层

@RestController == @Controller + ReponseBody
@RequestMapping(“/books”)

@RestController //@Controller + ReponseBody
@RequestMapping("/books")
public class BookController {
    
	//@RequestMapping(method = RequestMethod.POST)
    @PostMapping
    public String save(@RequestBody Book book){
        System.out.println("book save..." + book);
        return "{'module':'book save'}";
    }

    //@RequestMapping(value = "/{id}",method = RequestMethod.DELETE)
    @DeleteMapping("/{id}")
    public String delete(@PathVariable Integer id){
        System.out.println("book delete..." + id);
        return "{'module':'book delete'}";
    }

    //@RequestMapping(method = RequestMethod.PUT)
    @PutMapping
    public String update(@RequestBody Book book){
        System.out.println("book update..." + book);
        return "{'module':'book update'}";
    }

    //@RequestMapping(value = "/{id}",method = RequestMethod.GET)
    @GetMapping("/{id}")
    public String getById(@PathVariable Integer id){
        System.out.println("book getById..." + id);
        return "{'module':'book getById'}";
    }

    //@RequestMapping(method = RequestMethod.GET)
    @GetMapping
    public String getAll(){
        System.out.println("book getAll...");
        return "{'module':'book getAll'}";
    }
    
}