springboot整合springmvc

1、创建springboot项目，勾选Spring web

1. 当前springboot选择的是2.6.13版本，jdk1.8
2. 尽量选2.几的springboot

2、在pom.xml中导入相应的坐标

<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId>
</dependency>         

3、配置application.yml，按需配置，可选

server:port: 8080spring:datasource:url: jdbc:mysql://localhost:3306/mydbusername: myuserpassword: mypassworddriver-class-name: com.mysql.cj.jdbc.Driverservlet:multipart:max-file-size: 10MB # 设置单个文件最大上传大小max-request-size: 50MB # 设置请求的最大总数据大小enabled: true # 开启文件上传支持format:date-time-patterns:- yyyy-MM-dd HH:mm:ss # 日期时间格式-mvc:static-path-pattern: /static/** # 指定静态资源的访问路径模式resources:static-locations: file:/path/to/your/static/files/ # 指定静态资源文件的存储位置view:prefix: /WEB-INF/views/ # view前缀suffix: .jsp # view后缀，如：.jsp

4、创建controller包，报下新建UserController进行测试

package com.example.controller;import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;@RestController
@RequestMapping("user")
public class UserController {@GetMapping("hello")public String test(){return "hello ssm";}
}//访问http://localhost:8080/user/hello，返回hello ssm即为测试成功

5、访问静态资源

默认的静态资源路径为：classpath:/META-INF/resources/classpath:/resources/classpath:/static/（一般放置在这个文件夹下）classpath:/public/只要静态资源放在这些目录中任何一个，SpringMVC都会帮我们处理

6、相关注解

1、@RequestMapping

1. 用于Controller类、类中方法上，用来处理请求地址映射的注解
2. @RequestMapping(value = “/login”,produces = “application/json;charset=utf-8”, method = RequestMethod.GET)
   1. value：url的值，
   2. method：提交方式 ，get或者post
   3. produces：指定响应体返回类型和编码
3. @GetMapping，与@RequestMapping作用一致，但指定必须为get请求，且只能用在类上
4. @PostMapping，与@RequestMapping作用一致，但指定必须为post请求，且只能用在类上

2、@RequestParam

1. 用于Controller类的方法参数前，如4中test()如果有参数，即可使用test(@RequestParam String name)
2. @RequestParam(value=“username”, required=true, defaultValue=“zhang”) String name)
   1. value表示 入参的请求参数名字，前端传过来的必须和这个名称一样
   2. required默认值是true，意思为该参数必传
   3. defaultValue表示默认值，当前设定为zhang
3. 注解可用于map与对象：test(@RequestParam Map query）、test(@RequestParam User user）

3、@RequestBody

1. 用于Controller类的方法上，效果是接收JSON数据

4、@PathVariable

1. 拥有绑定url中的占位符的。例如：url中有/delete/{id}，{id}就是占位符
2. deleteById(@PathVariable (“id”) String uid）：将占位符{id}的值绑定给了形参uid

5、@ResponseBody

1. 用于Controller类的方法上，效果是返回JSON数据给前端。

2. 返回值一般写AjaxResult

3. AjaxResult工具类

   package com.pj.util;import java.io.Serializable;
   import java.util.List;/*** ajax请求返回Json格式数据的封装 */
   public class AjaxJson implements Serializable{private static final long serialVersionUID = 1L;	// 序列化版本号public static final int CODE_SUCCESS = 200;			// 成功状态码public static final int CODE_ERROR = 500;			// 错误状态码public static final int CODE_WARNING = 501;			// 警告状态码public static final int CODE_NOT_JUR = 403;			// 无权限状态码public static final int CODE_NOT_LOGIN = 401;		// 未登录状态码public static final int CODE_INVALID_REQUEST = 400;	// 无效请求状态码public int code; 	// 状态码public String msg; 	// 描述信息 public Object data; // 携带对象public Long dataCount;	// 数据总数，用于分页 /*** 返回code  * @return*/public int getCode() {return this.code;}/*** 给msg赋值，连缀风格*/public AjaxJson setMsg(String msg) {this.msg = msg;return this;}public String getMsg() {return this.msg;}/*** 给data赋值，连缀风格*/public AjaxJson setData(Object data) {this.data = data;return this;}/*** 将data还原为指定类型并返回*/@SuppressWarnings("unchecked")public <T> T getData(Class<T> cs) {return (T) data;}// ============================  构建  ================================== public AjaxJson(int code, String msg, Object data, Long dataCount) {this.code = code;this.msg = msg;this.data = data;this.dataCount = dataCount;}// 返回成功public static AjaxJson getSuccess() {return new AjaxJson(CODE_SUCCESS, "ok", null, null);}public static AjaxJson getSuccess(String msg) {return new AjaxJson(CODE_SUCCESS, msg, null, null);}public static AjaxJson getSuccess(String msg, Object data) {return new AjaxJson(CODE_SUCCESS, msg, data, null);}public static AjaxJson getSuccessData(Object data) {return new AjaxJson(CODE_SUCCESS, "ok", data, null);}public static AjaxJson getSuccessArray(Object... data) {return new AjaxJson(CODE_SUCCESS, "ok", data, null);}// 返回失败public static AjaxJson getError() {return new AjaxJson(CODE_ERROR, "error", null, null);}public static AjaxJson getError(String msg) {return new AjaxJson(CODE_ERROR, msg, null, null);}// 返回警告 public static AjaxJson getWarning() {return new AjaxJson(CODE_ERROR, "warning", null, null);}public static AjaxJson getWarning(String msg) {return new AjaxJson(CODE_WARNING, msg, null, null);}// 返回未登录public static AjaxJson getNotLogin() {return new AjaxJson(CODE_NOT_LOGIN, "未登录，请登录后再次访问", null, null);}// 返回没有权限的 public static AjaxJson getNotJur(String msg) {return new AjaxJson(CODE_NOT_JUR, msg, null, null);}// 返回一个自定义状态码的public static AjaxJson get(int code, String msg){return new AjaxJson(code, msg, null, null);}// 返回分页和数据的public static AjaxJson getPageData(Long dataCount, Object data){return new AjaxJson(CODE_SUCCESS, "ok", data, dataCount);}// 返回，根据受影响行数的(大于0=ok，小于0=error)public static AjaxJson getByLine(int line){if(line > 0){return getSuccess("ok", line);}return getError("error").setData(line); }// 返回，根据布尔值来确定最终结果的  (true=ok，false=error)public static AjaxJson getByBoolean(boolean b){return b ? getSuccess("ok") : getError("error"); }/* (non-Javadoc)* @see java.lang.Object#toString()*/@SuppressWarnings("rawtypes")@Overridepublic String toString() {String data_string = null;if(data == null){} else if(data instanceof List){data_string = "List(length=" + ((List)data).size() + ")";} else {data_string = data.toString();}return "{"+ "\"code\": " + this.getCode()+ ", \"msg\": \"" + this.getMsg() + "\""+ ", \"data\": " + data_string+ ", \"dataCount\": " + dataCount+ "}";}}
   

7、请求转发和重定向

1、forward请求转发

/*** 使用forward关键字进行请求转发 * "forward:转发的JSP路径"，不走视图解析器了，所以需要编写完整的路径 * @return * @throws Exception */@RequestMapping("/delete")public String delete() throws Exception {System.out.println("delete方法执行了...");// return "forward:/WEB-INF/pages/success.jsp"; return "forward:/user/findAll";}

2、redirect重定向

  /*** 重定向 * @return * @throws Exception */@RequestMapping("/count")public String count() throws Exception {System.out.println("count方法执行了...");return "redirect:/add.jsp";// return "redirect:/user/findAll"; }}

8、拦截器

1、新建Interceptor包，包下新建MyHandlerInterceptor文件

package com.example.Interceptor;import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;public class MyHandlerInterceptor implements HandlerInterceptor {@Overridepublic boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {System.out.println("Pre Handle: " + request.getMethod() + " " + request.getRequestURI());System.out.println("在控制器方法调用之前执行");return true; // 继续处理请求}@Overridepublic void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {System.out.println("Post Handle: " + request.getRequestURI());System.out.println("在控制器方法调用之后执行，但在视图渲染之前");}@Overridepublic void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {System.out.println("After Completion: " + request.getRequestURI());System.out.println("在整个请求完成后执行，无论是否出现异常");}
}

2、XML 配置

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xmlns:context="http://www.springframework.org/schema/context"xmlns:aop="http://www.springframework.org/schema/aop"xmlns:mvc="http://www.springframework.org/schema/mvc"xsi:schemaLocation="http://www.springframework.org/schema/beanshttps://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/contexthttps://www.springframework.org/schema/context/spring-context.xsdhttp://www.springframework.org/schema/aophttps://www.springframework.org/schema/aop/spring-aop.xsd"><mvc:interceptors><bean class="com.example.Interceptor.MyHandlerInterceptor" /></mvc:interceptors>
</beans>

3、新建config包，包下新建WebMvcConfigurer文件

package com.example.config;import com.example.Interceptor.MyHandlerInterceptor;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;@Configuration
public class WebConfig implements WebMvcConfigurer {@Overridepublic void addInterceptors(InterceptorRegistry registry) {registry.addInterceptor(new MyHandlerInterceptor()).addPathPatterns("/**") // 指定拦截器的应用路径.excludePathPatterns("/resources/**", "/static/**"); // 排除静态资源}
}

拦截器参考链接

springboot整合springmvc参考链接