SpringMVC实现RESTful服务

超、凢脫俗 2022-07-13 07:40 246阅读 0赞

1、SpringMVC实现RESTful服务

1.  SpringMVC原生态的支持了REST风格的架构设计。
2.  所涉及到的注解和类

*  @RequestMapping
 *  @PathVariable
 *  @ResponseBody
 *  ResponseEntity  
    
 *  HttpStatus  
    
 *  ……

2、查询资源

2.1 查询资源的代码实现

@RequestMapping(value = "{id}", method = RequestMethod.GET)
    	public ResponseEntity<User> queryUserById(@PathVariable("id") Long id) {
    		try {
    			User user = this.userService.queryUserById(id);
    			if (null == user) {
    				// 资源不存在 404
    				return ResponseEntity.status(HttpStatus.NOT_FOUND).body(null);
    			}
    			// 资源存在 200
    			return ResponseEntity.status(HttpStatus.OK).body(user);
    		} catch (Exception e) {
    			e.printStackTrace();
    		}
    		// 出现异常，服务器内部错误
    		// 500
    		return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body(null);
    	}

2.2 查询资源的测试

要查询的资源存在

![20161230210756900][]

要查询的资源不存在

![20161230210806619][]

2.3 使用忽略@JsonIgnore,在返回User时，忽略密码属性的信息

![20161230210551828][]

3、新增资源

3.1新增资源的代码实现

/**
    	 * 新增资源
    	 * 
    	 * @param user
    	 * @return
    	 */
    	@RequestMapping(method = RequestMethod.POST)
    	public ResponseEntity<Void> saveUser(User user) {
    		try {
    			this.userService.saveUser(user);
    			return ResponseEntity.status(HttpStatus.CREATED).build();
    		} catch (Exception e) {
    			e.printStackTrace();
    		}
    		// 出现异常，服务器内部错误
    		// 500
    		return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body(
    				null);
    	}

3.2新增资源的测试

![20161230211313549][]

4、更新资源

4.0 **默认情况下，PUT请求是无法提交表单数据的**，需要在**web.xml**中添加过滤器解决

<filter>
    		<filter-name>HttpMethodFilter</filter-name>
    		<filter-class>org.springframework.web.filter.HttpPutFormContentFilter</filter-class>
    	</filter>
    	<filter-mapping>
    		<filter-name>HttpMethodFilter</filter-name>
    		<url-pattern>/*</url-pattern>
    	</filter-mapping>

4.1  更新资源的代码实现

/**
    	 * 修改资源
    	 * 
    	 * @param user
    	 * @return
    	 */
    	@RequestMapping(method = RequestMethod.PUT)
    	public ResponseEntity<Void> updateUser(User user) {
    		try {
    			this.userService.updateUser(user);
    			// 204
    			return ResponseEntity.status(HttpStatus.NO_CONTENT).build();
    		} catch (Exception e) {
    			e.printStackTrace();
    		}
    		// 出现异常，服务器内部错误
    		// 500
    		return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body(
    				null);
    	}

4.2  更新资源的测试

![20161230211700457][]

5、删除资源

5.0 **默认情况下，Delete请求是无法提交表单数据的**，需要在**web.xml**中添加过滤器解决

<filter>
    		<filter-name>HiddenHttpMethodFilter</filter-name>
    		<filter-class>org.springframework.web.filter.HiddenHttpMethodFilter</filter-class>
    	</filter>
    	<filter-mapping>
    		<filter-name>HiddenHttpMethodFilter</filter-name>
    		<url-pattern>/*</url-pattern>
    	</filter-mapping>

5.1删除资源的代码实现

/**
    	 * 删除资源
    	 * 
    	 * @param user
    	 * @return
    	 */
    	@RequestMapping(method = RequestMethod.DELETE)
    	public ResponseEntity<Void> deleteUser(
    			@RequestParam(value = "id", defaultValue = "0") Long id) {
    		try {
    			this.userService.deleteById(id);
    			// 204
    			return ResponseEntity.status(HttpStatus.NO_CONTENT).build();
    		} catch (Exception e) {
    			e.printStackTrace();
    		}
    		// 出现异常，服务器内部错误
    		// 500
    		return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body(
    				null);
    	}

5.2  删除资源的测试

![20161230212005302][]

6、完整的实现代码

import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.http.HttpStatus;
    import org.springframework.http.ResponseEntity;
    import org.springframework.stereotype.Controller;
    import org.springframework.web.bind.annotation.PathVariable;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RequestMethod;
    import org.springframework.web.bind.annotation.RequestParam;
    import cn.itcast.user.pojo.User;
    import cn.itcast.user.service.UserService;
    
    @RequestMapping("new/user")
    @Controller
    public class RestUserController {
    
    	@Autowired
    	private UserService userService;
    
    	@RequestMapping(value = "{id}", method = RequestMethod.GET)
    	public ResponseEntity<User> queryUserById(@PathVariable("id") Long id) {
    		try {
    			User user = this.userService.queryUserById(id);
    			if (null == user) {
    				// 资源不存在 404
    				return ResponseEntity.status(HttpStatus.NOT_FOUND).body(null);
    			}
    			// 资源存在 200
    			return ResponseEntity.status(HttpStatus.OK).body(user);
    		} catch (Exception e) {
    			e.printStackTrace();
    		}
    		// 出现异常，服务器内部错误
    		// 500
    		return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body(
    				null);
    	}
    
    	/**
    	 * 新增资源
    	 * 
    	 * @param user
    	 * @return
    	 */
    	@RequestMapping(method = RequestMethod.POST)
    	public ResponseEntity<Void> saveUser(User user) {
    		try {
    			this.userService.saveUser(user);
    			// 201
    			return ResponseEntity.status(HttpStatus.CREATED).build();
    		} catch (Exception e) {
    			e.printStackTrace();
    		}
    		// 出现异常，服务器内部错误
    		// 500
    		return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body(
    				null);
    	}
    
    	/**
    	 * 修改资源
    	 * 
    	 * @param user
    	 * @return
    	 */
    	@RequestMapping(method = RequestMethod.PUT)
    	public ResponseEntity<Void> updateUser(User user) {
    		try {
    			this.userService.updateUser(user);
    			// 204
    			return ResponseEntity.status(HttpStatus.NO_CONTENT).build();
    		} catch (Exception e) {
    			e.printStackTrace();
    		}
    		// 出现异常，服务器内部错误
    		// 500
    		return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body(
    				null);
    	}
    
    	/**
    	 * 删除资源
    	 * 
    	 * @param user
    	 * @return
    	 */
    	@RequestMapping(method = RequestMethod.DELETE)
    	public ResponseEntity<Void> deleteUser(
    			@RequestParam(value = "id", defaultValue = "0") Long id) {
    		try {
    			this.userService.deleteById(id);
    			// 204
    			return ResponseEntity.status(HttpStatus.NO_CONTENT).build();
    		} catch (Exception e) {
    			e.printStackTrace();
    		}
    		// 出现异常，服务器内部错误
    		// 500
    		return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body(
    				null);
    	}
    }

7、[源码下载][Link 1]

[20161230210756900]: /images/20220713/8b64d6b4b56b4aa8a28c8c5cd4af5448.png
[20161230210806619]: /images/20220713/d01136653d094ab1b970a1c5f9c61c13.png
[20161230210551828]: /images/20220713/101c95251997482da8734f92f64888e2.png
[20161230211313549]: /images/20220713/544d7b9b3b16473a95167e6e11169297.png
[20161230211700457]: /images/20220713/e89901b028b54c2b9b178d2e3f8ea126.png
[20161230212005302]: /images/20220713/fa285fec26204d8ab6f9be0f1be862d6.png
[Link 1]: http://pan.baidu.com/s/1bo6XAqz