• Json和全局异常处理

    目录

    1、SpringMVC对Json的支持

    1.1、Json的各种场景

    1.2、pom依赖

    1.3、Springmvc.xml配置

    1.4、后台代码

    1.4.1、ClazzBiz

    1.4.2、ClazzBizImpl

    1.4.3、ClazzMapper.java

    1.4.4、ClazzMapper.xml

    1.4.5、JsonController

    1.5、前台测试

    1.5.1、Index.jsp

    1.5.2、运行效果

    2、Springmvc的全局异常处理

    2.1、Springmvc自带的简单异常处理器

    2.2、通过HandlerExceptionResovler接口实现全局异常

    2.2.1、GlobalException

    2.2.2、GlobalException

    2.2.3、controller层

    2.3、使用@controllerAdvice+@ExceptionHandler实现全局异常处理

    2.4、全局异常处理Json返回

    1、SpringMVC对Json的支持

    1.1、Json的各种场景

    1. 1.1返回List
    2. 1.2返回List
    3. 1.3返回T
    4. 1.4返回Map
    5. 1.5返回混合
    6. 1.6返回JSON字符串

    1.2、pom依赖

    1.  <dependency>
    2.       <groupId>com.fasterxml.jackson.core</groupId>
    3.       <artifactId>jackson-databind</artifactId>
    4.       <version>2.9.3</version>
    5.     </dependency>
    6.     <dependency>
    7.       <groupId>com.fasterxml.jackson.core</groupId>
    8.       <artifactId>jackson-core</artifactId>
    9.       <version>2.9.3</version>
    10.     </dependency>
    11.     <dependency>
    12.       <groupId>com.fasterxml.jackson.core</groupId>
    13.       <artifactId>jackson-annotations</artifactId>
    14.       <version>2.9.3</version>
    15.     </dependency>
    16.

    1.3、Springmvc.xml配置

    1. <!--支持json数据返回的适配器-->
    2.     <bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter">
    3.         <property name="messageConverters">
    4.             <list>
    5.                 <ref bean="mappingJackson2HttpMessageConverter"/>
    6.             </list>
    7.         </property>
    8.     </bean>
    9.     <bean id="mappingJackson2HttpMessageConverter"
    10.           class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
    11.         <!--处理中文乱码以及避免IE执行AJAX时，返回JSON出现下载文件-->
    12.         <property name="supportedMediaTypes">
    13.             <list>
    14.                 <value>text/html;charset=UTF-8</value>
    15.                 <value>text/json;charset=UTF-8</value>
    16.                 <value>application/json;charset=UTF-8</value>
    17.             </list>
    18.         </property>
    19.     </bean>

    1.4、后台代码

    1.4.1、ClazzBiz

    1. package com.ssr.ssm2.biz;
    2.  
    3. import com.ssr.ssm2.model.Clazz;
    4. import com.ssr.ssm2.uitl.PageBean;
    5.  
    6. import java.util.List;
    7. import java.util.Map;
    8.  
    9. public interface ClazzBiz {
    10.     int deleteByPrimaryKey(Integer cid);
    11.  
    12.     int insert(Clazz record);
    13.  
    14.     int insertSelective(Clazz record);
    15.  
    16.     Clazz selectByPrimaryKey(Integer cid);
    17.  
    18.     List listPager(Clazz clazz, PageBean pageBean);
    19.  
    20.     int updateByPrimaryKeySelective(Clazz record);
    21.  
    22.     int updateByPrimaryKey(Clazz record);
    23.  
    24.     List listMapPager(Clazz clazz, PageBean pageBean);
    25.  
    26. }

    1.4.2、ClazzBizImpl

    1. package com.ssr.ssm2.biz.impl;
    2.  
    3. import com.ssr.ssm2.biz.ClazzBiz;
    4. import com.ssr.ssm2.mapper.ClazzMapper;
    5. import com.ssr.ssm2.model.Clazz;
    6. import com.ssr.ssm2.uitl.PageBean;
    7. import org.springframework.beans.factory.annotation.Autowired;
    8. import org.springframework.stereotype.Service;
    9.  
    10. import java.util.List;
    11. import java.util.Map;
    12.  
    13. /**
    14.  * @author四金
    15.  * @site 2261696885
    16.  * @company 浪琴湾总公司
    17.  * @create 2022-08-17-19:27
    18.  */
    19. @Service
    20. public class ClazzBizImpl implements ClazzBiz {
    21.     @Autowired
    22.     private ClazzMapper clazzMapper;
    23.     @Override
    24.     public int deleteByPrimaryKey(Integer cid) {
    25.         return clazzMapper.deleteByPrimaryKey(cid);
    26.     }
    27.  
    28.     @Override
    29.     public int insert(Clazz record) {
    30.         return clazzMapper.insert(record);
    31.     }
    32.  
    33.     @Override
    34.     public int insertSelective(Clazz record) {
    35.         return clazzMapper.insertSelective(record);
    36.     }
    37.  
    38.     @Override
    39.     public Clazz selectByPrimaryKey(Integer cid) {
    40.         return clazzMapper.selectByPrimaryKey(cid);
    41.     }
    42.  
    43.     @Override
    44.     public List listPager(Clazz clazz, PageBean pageBean) {
    45.         return clazzMapper.listPager(clazz);
    46.     }
    47.  
    48.     @Override
    49.     public int updateByPrimaryKeySelective(Clazz record) {
    50.         return clazzMapper.updateByPrimaryKeySelective(record);
    51.     }
    52.  
    53.     @Override
    54.     public int updateByPrimaryKey(Clazz record) {
    55.         return clazzMapper.updateByPrimaryKey(record);
    56.     }
    57.  
    58.     @Override
    59.     public List listMapPager(Clazz clazz, PageBean pageBean) {
    60.         if(true)
    61.             throw new RuntimeException("查询班级信息异常、异常存在于ClazzBizImpl.list方法中");
    62.         return clazzMapper.listMapPager(clazz);
    63.     }
    64. }

    1.4.3、ClazzMapper.java

    1. package com.ssr.ssm2.mapper;
    2.  
    3. import com.ssr.ssm2.model.Clazz;
    4. import org.springframework.stereotype.Repository;
    5.  
    6. import java.util.List;
    7. import java.util.Map;
    8.  
    9. @Repository
    10. public interface ClazzMapper {
    11.     int deleteByPrimaryKey(Integer cid);
    12.  
    13.     int insert(Clazz record);
    14.  
    15.     int insertSelective(Clazz record);
    16.  
    17.     Clazz selectByPrimaryKey(Integer cid);
    18.  
    19.     List listPager(Clazz clazz);
    20.  
    21.     List listMapPager(Clazz clazz);
    22.  
    23.     int updateByPrimaryKeySelective(Clazz record);
    24.  
    25.     int updateByPrimaryKey(Clazz record);
    26. }

    1.4.4、ClazzMapper.xml

    1. <?xml version="1.0" encoding="UTF-8" ?>
    2. <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
    3. <mapper namespace="com.ssr.ssm2.mapper.ClazzMapper" >
    4.   <resultMap id="BaseResultMap" type="com.ssr.ssm2.model.Clazz" >
    5.     <constructor >
    6.       <idArg column="cid" jdbcType="INTEGER" javaType="java.lang.Integer" />
    7.       <arg column="cname" jdbcType="VARCHAR" javaType="java.lang.String" />
    8.       <arg column="cteacher" jdbcType="VARCHAR" javaType="java.lang.String" />
    9.       <arg column="pic" jdbcType="VARCHAR" javaType="java.lang.String" />
    10.     </constructor>
    11.   </resultMap>
    12.   <sql id="Base_Column_List" >
    13.     cid, cname, cteacher, pic
    14.   </sql>
    15.   <select id="selectByPrimaryKey" resultMap="BaseResultMap" parameterType="java.lang.Integer" >
    16.     select 
    17.     <include refid="Base_Column_List" />
    18.     from t_struts_class
    19.     where cid = #{cid,jdbcType=INTEGER}
    20.   </select>
    21.  
    22.   <select id="listPager" resultType="com.ssr.ssm2.model.Clazz" parameterType="com.ssr.ssm2.model.Clazz" >
    23.     select
    24.     <include refid="Base_Column_List" />
    25.     from t_struts_class
    26.     <where>
    27.       <if test="cname != null and cname != ''">
    28.         and cname like CONCAT('%',#{cname},'%')
    29.       </if>
    30.       <if test="cid != null and cid != ''">
    31.         and cid = #{cid}
    32.       </if>
    33.     </where>
    34.   </select>
    35.  
    36.   <select id="listMapPager" resultType="java.util.Map" parameterType="com.ssr.ssm2.model.Clazz" >
    37.     select
    38.     <include refid="Base_Column_List" />
    39.     from t_struts_class
    40.     <where>
    41.       <if test="cname != null and cname != ''">
    42.         and cname like CONCAT('%',#{cname},'%')
    43.       </if>
    44.       <if test="cid != null and cid != ''">
    45.         and cid = #{cid}
    46.       </if>
    47.     </where>
    48.   </select>
    49.  
    50.  
    51.   <delete id="deleteByPrimaryKey" parameterType="java.lang.Integer" >
    52.     delete from t_struts_class
    53.     where cid = #{cid,jdbcType=INTEGER}
    54.   </delete>
    55.   <insert id="insert" parameterType="com.ssr.ssm2.model.Clazz" >
    56.     insert into t_struts_class (cid, cname, cteacher, 
    57.       pic)
    58.     values (#{cid,jdbcType=INTEGER}, #{cname,jdbcType=VARCHAR}, #{cteacher,jdbcType=VARCHAR}, 
    59.       #{pic,jdbcType=VARCHAR})
    60.   </insert>
    61.   <insert id="insertSelective" parameterType="com.ssr.ssm2.model.Clazz" >
    62.     insert into t_struts_class
    63.     <trim prefix="(" suffix=")" suffixOverrides="," >
    64.       <if test="cid != null" >
    65.         cid,
    66.       </if>
    67.       <if test="cname != null" >
    68.         cname,
    69.       </if>
    70.       <if test="cteacher != null" >
    71.         cteacher,
    72.       </if>
    73.       <if test="pic != null" >
    74.         pic,
    75.       </if>
    76.     </trim>
    77.     <trim prefix="values (" suffix=")" suffixOverrides="," >
    78.       <if test="cid != null" >
    79.         #{cid,jdbcType=INTEGER},
    80.       </if>
    81.       <if test="cname != null" >
    82.         #{cname,jdbcType=VARCHAR},
    83.       </if>
    84.       <if test="cteacher != null" >
    85.         #{cteacher,jdbcType=VARCHAR},
    86.       </if>
    87.       <if test="pic != null" >
    88.         #{pic,jdbcType=VARCHAR},
    89.       </if>
    90.     </trim>
    91.   </insert>
    92.   <update id="updateByPrimaryKeySelective" parameterType="com.ssr.ssm2.model.Clazz" >
    93.     update t_struts_class
    94.     <set >
    95.       <if test="cname != null" >
    96.         cname = #{cname,jdbcType=VARCHAR},
    97.       </if>
    98.       <if test="cteacher != null" >
    99.         cteacher = #{cteacher,jdbcType=VARCHAR},
    100.       </if>
    101.       <if test="pic != null" >
    102.         pic = #{pic,jdbcType=VARCHAR},
    103.       </if>
    104.     </set>
    105.     where cid = #{cid,jdbcType=INTEGER}
    106.   </update>
    107.   <update id="updateByPrimaryKey" parameterType="com.ssr.ssm2.model.Clazz" >
    108.     update t_struts_class
    109.     set cname = #{cname,jdbcType=VARCHAR},
    110.       cteacher = #{cteacher,jdbcType=VARCHAR},
    111.       pic = #{pic,jdbcType=VARCHAR}
    112.     where cid = #{cid,jdbcType=INTEGER}
    113.   </update>
    114. </mapper>

    1.4.5、JsonController

    1. package com.ssr.ssm2.controller;
    2.  
    3. import com.ssr.ssm2.biz.ClazzBiz;
    4. import com.ssr.ssm2.exception.GlobalException;
    5. import com.ssr.ssm2.model.Clazz;
    6. import com.ssr.ssm2.uitl.PageBean;
    7. import org.springframework.beans.factory.annotation.Autowired;
    8. import org.springframework.stereotype.Controller;
    9. import org.springframework.web.bind.annotation.RequestMapping;
    10.  
    11. import javax.servlet.http.HttpServletRequest;
    12. import java.util.HashMap;
    13. import java.util.List;
    14. import java.util.Map;
    15.  
    16. /**
    17.  * @author四金
    18.  * @site 2261696885
    19.  * @company 浪琴湾总公司
    20.  * @create 2022-08-22-16:34
    21.  */
    22. @Controller
    23. @RequestMapping("/clz/json")
    24. public class JsonController {
    25.     @Autowired
    26.     private ClazzBiz clazzBiz;
    27.  
    28.     @RequestMapping("/clzEdit")
    29.     public String clzEdit(){
    30.         System.out.println("JsonController.clzEdit");
    31.         return "clzEdit";
    32.     }
    33.  
    34.     //    list<T>的格式
    35.     @RequestMapping("/list")
    36.     public List<Clazz> list(HttpServletRequest request,Clazz clazz){
    37.         PageBean pageBean = new PageBean();
    38.         pageBean.setRequest(request);
    39.         if(true)
    40.         throw new RuntimeException("查询班级信息异常、异常存在于JsonController.list方法中");
    41. //        [{},{}]
    42.         return this.clazzBiz.listPager(clazz,pageBean);
    43.     }
    44.  
    45.     //    list<Map>的格式
    46.     @RequestMapping("/listMap")
    47.     public List<Map> listMap(HttpServletRequest request, Clazz clazz){
    48.         PageBean pageBean = new PageBean();
    49.         pageBean.setRequest(request);
    50. //        [{},{}]
    51.         return this.clazzBiz.listMapPager(clazz,pageBean);
    52.     }
    53.  
    54.     //    map的格式
    55.     @RequestMapping("/map")
    56.     public Map map(HttpServletRequest request, Clazz clazz){
    57.         PageBean pageBean = new PageBean();
    58.         pageBean.setRequest(request);
    59. //        [{},{}]
    60.         return this.clazzBiz.listMapPager(clazz,pageBean).get(0);
    61.     }
    62.  
    63.     //    map的格式
    64.     @RequestMapping("/load")
    65.     public Clazz load(HttpServletRequest request, Clazz clazz){
    66. //        http://localhost:8080/clz/json/load?cid=2
    67.         PageBean pageBean = new PageBean();
    68.         pageBean.setRequest(request);
    69.         if(true)
    70.             throw new GlobalException("系统繁忙，请参考E007；");
    71. //        [{},{}]
    72.         return this.clazzBiz.listPager(clazz,pageBean).get(0);
    73.     }
    74.  
    75.     //    {
    76. //    msg:"",
    77. //    code:200,
    78. //    data:[]
    79. //    pageBean:{}
    80. //    }
    81.     @RequestMapping("/hunhe")
    82.     public Map hunhe(HttpServletRequest request, Clazz clazz){
    83. //        http://localhost:8080/clz/json/load?cid=2
    84.         PageBean pageBean = new PageBean();
    85.         pageBean.setRequest(request);
    86.         List<Clazz> lst = this.clazzBiz.listPager(clazz, pageBean);
    87.         Map map = new HashMap();
    88.         map.put("date",lst);
    89.         map.put("pagebean",pageBean);
    90.         return map;
    91.     }
    92. }

    1.5、前台测试

    1.5.1、Index.jsp

    1. <%--
    2.   Created by IntelliJ IDEA.
    3.   User: Administrator
    4.   Date: 2022/8/22
    5.   Time: 17:14
    6.   To change this template use File | Settings | File Templates.
    7. --%>
    8. <%@ page contentType="text/html;charset=UTF-8" language="java" %>
    9. <html>
    10. <head>
    11.     <title>测试json数据返回</title>
    12. </head>
    13. <body>
    14. <a href="${pageContext.request.contextPath}/clz/json/list">返回list&lt;T&gt;对象</a><hr>
    15. <a href="${pageContext.request.contextPath}/clz/json/listMap">返回list&lt;Map&gt;对象</a><hr>
    16. <a href="${pageContext.request.contextPath}/clz/json/load?cid=1">返回T对象</a><hr>
    17. <a href="${pageContext.request.contextPath}/clz/json/map?cid=1">返回map对象</a><hr>
    18. <a href="${pageContext.request.contextPath}/clz/json/hunhe">返回混合对象</a><hr>
    19. </body>
    20. </html>

    1.5.2、运行效果

     返回list

    返回list

    返回T对象

     

    返回 map对象

     

    返回混合对象

    2、Springmvc的全局异常处理

    2.1、Springmvc自带的简单异常处理器

    2.     <bean class="org.springframework.web.servlet.handler.SimpleMappingExceptionResolver">
    3.         
    4.         <property name="defaultErrorView" value="error"/>
    5.         
    6.         <property name="exceptionAttribute" value="ex"/>
    7.         
    8.         <property name="exceptionMappings">
    9.             <props>
    10.                 <prop key="java.lang.RuntimeException">errorprop>
    11.             props>
    12.             
    13.         property>
    14.     bean>
    15.

    Error.jsp

    1. <%--
    2.   Created by IntelliJ IDEA.
    3.   User: Administrator
    4.   Date: 2022/8/22
    5.   Time: 19:15
    6.   To change this template use File | Settings | File Templates.
    7. --%>
    8. <%@ page contentType="text/html;charset=UTF-8" language="java" %>
    9. <html>
    10. <head>
    11.     <title>错误信息页面</title>
    12. </head>
    13. <body>
    14. ${msg}
    15. <hr>
    16. ${ex}
    17. </body>
    18. </html>

    2.2、通过HandlerExceptionResovler接口实现全局异常

    2.2.1、GlobalException

    1. package com.ssr.ssm2.exception;
    2.  
    3. /**
    4.  * @author四金
    5.  * @site 2261696885
    6.  * @company 浪琴湾总公司
    7.  * @create 2022-08-22-19:44
    8.  */
    9. public class GlobalException extends RuntimeException {
    10.     public GlobalException() {
    11.     }
    12.  
    13.     public GlobalException(String message) {
    14.         super(message);
    15.     }
    16.  
    17.     public GlobalException(String message, Throwable cause) {
    18.         super(message, cause);
    19.     }
    20.  
    21.     public GlobalException(Throwable cause) {
    22.         super(cause);
    23.     }
    24.  
    25.     public GlobalException(String message, Throwable cause, boolean enableSuppression, boolean writableStackTrace) {
    26.         super(message, cause, enableSuppression, writableStackTrace);
    27.     }
    28. }

    2.2.2、GlobalHandlerExceptionResovler 

    1. package com.ssr.ssm2.exception;
    2.  
    3. import org.springframework.stereotype.Component;
    4. import org.springframework.web.servlet.HandlerExceptionResolver;
    5. import org.springframework.web.servlet.ModelAndView;
    6.  
    7. import javax.servlet.http.HttpServletRequest;
    8. import javax.servlet.http.HttpServletResponse;
    9.  
    10. /**
    11.  * @author四金
    12.  * @site 2261696885
    13.  * @company 浪琴湾总公司
    14.  * @create 2022-08-22-19:28
    15.  *
    16.  * 处理全局异常的解析器
    17.  *
    18.  */
    19. //@Component
    20. public class GlobalHandlerExceptionResovler implements HandlerExceptionResolver {
    21.     /**
    22.      *
    23.      * @param httpServletRequest
    24.      * @param httpServletResponse
    25.      * @param o 目标对象
    26.      * @param e 目标对象执行，出现的异常对象
    27.      * @return
    28.      */
    29.     @Override
    30.     public ModelAndView resolveException(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) {
    31.         ModelAndView mv = new ModelAndView();
    32.         mv.setViewName("error");
    33.         if(e instanceof  GlobalException){
    34.             GlobalException exception = (GlobalException) e;
    35.             mv.addObject("ex",exception.getMessage());
    36.             mv.addObject("msg","全局异常，错误码501");
    37.         }
    38.         else if(e instanceof  RuntimeException){
    39.             RuntimeException exception = (RuntimeException) e;
    40.             mv.addObject("ex",exception.getMessage());
    41.             mv.addObject("msg","运行时异常，错误码601");
    42.         }
    43.         return mv;
    44.     }
    45. }

    2.2.3、controller层

    1. //    T
    2.     @ResponseBody
    3.     @RequestMapping("/load")
    4.     public Clazz load(HttpServletRequest request, Clazz clazz){
    5. //        http://localhost:8080/clz/json/load?cid=2
    6.         //        System.out.println("JsonController.list");
    7. //        PageBean pageBean=new PageBean();
    8. //        pageBean.setRequest(request);
    9.         //        {}
    10.         if(clazz.getCid()!=null){
    11.             List<Clazz> lst=this.clazzBiz.listPager(clazz,null);
    12.             if(true)
    13.                 throw new GlobalException("错误出现在JsonController.load");
    14.             return lst.get(0);
    15.         }
    16.         return null;
    17.     }

    2.3、使用@controllerAdvice+@ExceptionHandler实现全局异常处理

    1. package com.ssr.ssm2.exception;
    2.  
    3. import org.springframework.web.bind.annotation.ControllerAdvice;
    4. import org.springframework.web.bind.annotation.ExceptionHandler;
    5. import org.springframework.web.servlet.ModelAndView;
    6.  
    7. /**
    8.  * @author四金
    9.  * @site 2261696885
    10.  * @company 浪琴湾总公司
    11.  * @create 2022-08-22-19:56
    12.  */
    13. //@ControllerAdvice
    14. public class GlobalExceptionResolver {
    15.     @ExceptionHandler
    16.     public ModelAndView handler(Exception e){
    17.         ModelAndView mv = new ModelAndView();
    18.         mv.setViewName("error");
    19.         if(e instanceof  GlobalException){
    20.             GlobalException exception = (GlobalException) e;
    21.             mv.addObject("ex",exception.getMessage());
    22.             mv.addObject("msg","全局异常，GlobalExceptionResolver错误码501");
    23.         }
    24.         else if(e instanceof  RuntimeException){
    25.             RuntimeException exception = (RuntimeException) e;
    26.             mv.addObject("ex",exception.getMessage());
    27.             mv.addObject("msg","运行时异常，GlobalExceptionResolver错误码601");
    28.         }
    29.         return mv;
    30.     }
    31. }

    2.4、全局异常处理Json返回

    1. package com.ssr.ssm2.exception;
    2.  
    3. import org.springframework.web.bind.annotation.ExceptionHandler;
    4. import org.springframework.web.bind.annotation.RestControllerAdvice;
    5. import org.springframework.web.servlet.ModelAndView;
    6.  
    7. import java.util.HashMap;
    8. import java.util.Map;
    9.  
    10. /**
    11.  * @author四金
    12.  * @site 2261696885
    13.  * @company 浪琴湾总公司
    14.  * @create 2022-08-22-19:56
    15.  *
    16.  * 档出现异常，统一想前端响应错误信息的json对象数据
    17.  */
    18. @RestControllerAdvice
    19. public class GlobalExceptionResolver2 {
    20. //    @ExceptionHandler
    21.     public Map handler(Exception e){
    22.         Map map = new HashMap();
    23.         if(e instanceof  GlobalException){
    24.             GlobalException exception = (GlobalException) e;
    25.             map.put("ex",exception.getMessage());
    26.             map.put("msg","全局异常，GlobalExceptionResolver错误码501");
    27.         }
    28.         else if(e instanceof  RuntimeException){
    29.             RuntimeException exception = (RuntimeException) e;
    30.             map.put("ex",exception.getMessage());
    31.             map.put("msg","运行时异常，GlobalExceptionResolver错误码601");
    32.         }
    33.         return map;
    34.     }
    35. }

    运行结果：

     

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  • 原文地址：https://blog.csdn.net/m0_65774688/article/details/126497100