• JSON和全局异常处理

    目录

    1.SpringMVC对JSON的支持

    1.1 JOSN的各种场景

    1.2 pom依赖

    1.3 Springmvc.xml配置

    1.4.后台代码：

    1.5 前端代码：

    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 

    代码展示：

    2.3;使用@ControllerAdvice+@ExceptionHandler实现全局异常

    2.4全局异常处理JSON返回

    1.SpringMVC对JSON的支持

    1.1 JOSN的各种场景

    1.1.1返回List

    1.1.2返回List

    1.1.3返回T

    1.1.4返回Map

    1.1.5返回混合

    1.1.6返回JSON字符串

    1.2 pom依赖

     

          com.fasterxml.jackson.core

          jackson-databind

          2.9.3

        

        

          com.fasterxml.jackson.core

          jackson-core

          2.9.3

        

        

          com.fasterxml.jackson.core

          jackson-annotations

          2.9.3

        

    1.3 Springmvc.xml配置

            

                

                    

                

            

        

        

              class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">

            

            

                

                    text/html;charset=UTF-8

                    text/json;charset=UTF-8

                    application/json;charset=UTF-8

                

            

        

    1.4.后台代码：

    clazzBiz:

    1. package com.xbb.ssm.biz;
    2.  
    3. import com.xbb.ssm.model.Clazz;
    4. import com.xbb.ssm.util.PageBean;
    5.  
    6. import java.util.List;
    7. import java.util.Map;
    8.  
    9. public interface ClassBiz {
    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.     int updateByPrimaryKeySelective(Clazz record);
    19.  
    20.     int updateByPrimaryKey(Clazz record);
    21.  
    22.     List listPager(Clazz clazz, PageBean pageBean);
    23.  
    24.     List listMapPager(Clazz clazz, PageBean pageBean);
    25.  
    26. }

    ClazzBizImpl:

    1. package com.xbb.ssm.biz.impl;
    2.  
    3. import com.xbb.ssm.biz.ClassBiz;
    4. import com.xbb.ssm.mapper.ClazzMapper;
    5. import com.xbb.ssm.model.Clazz;
    6. import com.xbb.ssm.util.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冰冰
    15.  * @create  2022-08-17 19:29
    16.  */
    17. @Service
    18. public class ClazzBizImpl implements ClassBiz {
    19.     @Autowired
    20.     private ClazzMapper clazzMapper;
    21.  
    22.     @Override
    23.     public int deleteByPrimaryKey(Integer cid) {
    24.         return clazzMapper.deleteByPrimaryKey(cid);
    25.     }
    26.  
    27.     @Override
    28.     public int insert(Clazz record) {
    29.         return clazzMapper.insert(record);
    30.     }
    31.  
    32.     @Override
    33.     public int insertSelective(Clazz record) {
    34.         return clazzMapper.insertSelective(record);
    35.     }
    36.  
    37.     @Override
    38.     public Clazz selectByPrimaryKey(Integer cid) {
    39.         return clazzMapper.selectByPrimaryKey(cid);
    40.     }
    41.  
    42.     @Override
    43.     public int updateByPrimaryKeySelective(Clazz record) {
    44.         return clazzMapper.updateByPrimaryKeySelective(record);
    45.     }
    46.  
    47.     @Override
    48.     public int updateByPrimaryKey(Clazz record) {
    49.         return clazzMapper.updateByPrimaryKey(record);
    50.     }
    51.  
    52.     @Override
    53.     public List listPager(Clazz clazz, PageBean pageBean) {
    54.         return clazzMapper.listPager(clazz);
    55.     }
    56.  
    57.     @Override
    58.     public List listMapPager(Clazz clazz, PageBean pageBean) {
    59.         return clazzMapper.listMapPager(clazz);
    60.     }
    61.  
    62. }

    ClazzMapper.java:

    1. package com.xbb.ssm.mapper;
    2.  
    3. import com.xbb.ssm.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. }

    ClazzMapper.xml:

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

    JsonController:

    1. package com.xbb.ssm.web;
    2.  
    3. import com.xbb.ssm.biz.ClazzBiz;
    4. import com.xbb.ssm.model.Clazz;
    5. import com.xbb.ssm.util.PageBean;
    6. import org.springframework.beans.factory.annotation.Autowired;
    7. import org.springframework.stereotype.Controller;
    8. import org.springframework.web.bind.annotation.RequestMapping;
    9. import org.springframework.web.bind.annotation.ResponseBody;
    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. @Controller
    18. @RequestMapping("/clz/json")
    19. public class JsonController {
    20.     @Autowired
    21.     private ClazzBiz clazzBiz;
    22.  
    23.     @ResponseBody
    24.     @RequestMapping("/clzEdit")
    25.     public String clzEdit(){
    26.         System.out.println("JsonController.list");
    27.         return "clzEdit";
    28.     }
    29.  
    30. //    list
    31.     @ResponseBody
    32.     @RequestMapping("/list")
    33.     public List list(HttpServletRequest request,Clazz clazz){
    34. //        System.out.println("JsonController.list");
    35.         PageBean pageBean=new PageBean();
    36.         pageBean.setRequest(request);
    37. //        [{},{}]
    38.         return this.clazzBiz.listPager(clazz,pageBean);
    39.     }
    40.  
    41. //    list
    42.     @ResponseBody
    43.     @RequestMapping("/listMap")
    44.     public List listMap(HttpServletRequest request, Clazz clazz){
    45. //        System.out.println("JsonController.list");
    46.         PageBean pageBean=new PageBean();
    47.         pageBean.setRequest(request);
    48. //        [{},{}]
    49.         return
    50.                 this.clazzBiz.listMapPager(clazz,pageBean);
    51.     }
    52.  
    53. //    Map
    54.     @ResponseBody
    55.     @RequestMapping("/map")
    56.     public Map map(HttpServletRequest request, Clazz clazz){
    57.     //        System.out.println("JsonController.list");
    58.         PageBean pageBean=new PageBean();
    59.         pageBean.setRequest(request);
    60.     //        {}
    61.         return this.clazzBiz.listMapPager(clazz,pageBean).get(0);
    62.     }
    63.  
    64. //    T
    65.     @ResponseBody
    66.     @RequestMapping("/load")
    67.     public Clazz load(HttpServletRequest request, Clazz clazz){
    68. //        http://localhost:8080/clz/json/load?cid=2
    69.         //        System.out.println("JsonController.list");
    70.         PageBean pageBean=new PageBean();
    71.         pageBean.setRequest(request);
    72.         //        {}
    73.         return this.clazzBiz.listPager(clazz,pageBean).get(0);
    74.     }
    75.  
    76. //    {
    77. //         msg:"",
    78. //        code:200,
    79. //        data:[],
    80. //         pageBean:{}
    81. //    }
    82.     @ResponseBody
    83.     @RequestMapping("/hunhe")
    84.     public Map hunhe(HttpServletRequest request, Clazz clazz){
    85.     //        http://localhost:8080/clz/json/load?cid=2
    86.         PageBean pageBean=new PageBean();
    87.         pageBean.setRequest(request);
    88.         List lst = this.clazzBiz.listPager(clazz, pageBean);
    89.         Map map = new HashMap();
    90.         map.put("data",lst);
    91.         map.put("pagebean",pageBean);
    92.         return map;
    93. //        return this.clazzBiz.listPager(clazz,pageBean).get(0);
    94.     }
    95. }
    96.

    1.5 前端代码：

    index.jsp：

    1. <%--
    2.   Created by IntelliJ IDEA.
    3.   User: Administrator
    4.   Date: 2022/8/22
    5.   Time: 16:50
    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="${pageContext.request.contextPath}/clz/json/list">返回List<T>对象a><hr>
    15.     <a href="${pageContext.request.contextPath}/clz/json/listMap">返回List<Map>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>
    21.

    效果展示：

     list：

    2.SpringMVC 的全局异常处理 

    2.1：SpringMVC自带的简单异常处理器

    配置文件：

    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.

    测试类：

    1. <%--
    2.   Created by IntelliJ IDEA.
    3.   User: Administrator
    4.   Date: 2022/8/22
    5.   Time: 17:17
    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>Titletitle>
    12. head>
    13. <body>
    14. ${ex}
    15. body>
    16. html>
    17.

    返回list对象：

    2.2：通过HandlerExceptionResovler接口实现全局异常 

    代码展示：

    GlobalException：

    1. package com.xbb.ssm.exception;
    2. /**
    3.  * @author冰冰
    4.  * @create  2022-08-23 20:33
    5.  */
    6. public class GlobalException extends RuntimeException{
    7.  
    8.     public GlobalException() {
    9.         super();
    10.     }
    11.  
    12.     public GlobalException(String message) {
    13.         super(message);
    14.     }
    15.  
    16.     public GlobalException(String message, Throwable cause) {
    17.         super(message, cause);
    18.     }
    19.  
    20.     public GlobalException(Throwable cause) {
    21.         super(cause);
    22.     }
    23.  
    24.     protected GlobalException(String message, Throwable cause, boolean enableSuppression, boolean writableStackTrace) {
    25.         super(message, cause, enableSuppression, writableStackTrace);
    26.     }
    27. }
    28.

    GlobalExceptionHandler：

    1. package com.xbb.ssm.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 冰冰
    12.  * @create 2022-08-23 20:50
    13.  */
    14. @Component
    15. public class GlobalExceptionHandler implements HandlerExceptionResolver {
    16.  
    17.     @Override
    18.     public ModelAndView resolveException(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) {
    19.         ModelAndView mv=new ModelAndView();
    20.         mv.setViewName("error");
    21.         if(e instanceof GlobalException){
    22.             GlobalException globalException = (GlobalException) e;
    23.             mv.addObject("ex",globalException);
    24.             mv.addObject("msg","全局异常");
    25.         }else if(e instanceof RuntimeException){
    26.             RuntimeException runtimeException = (RuntimeException) e;
    27.             mv.addObject("ex",runtimeException.getMessage());
    28.             mv.addObject("msg","运行时异常");
    29.         }
    30.         return mv;
    31.     }
    32. }
    33.

    GlobalExceptionHandler：

    1. package com.xbb.ssm.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 冰冰
    12.  * @create 2022-08-23 21:29
    13.  */
    14. @Component
    15. public class GlobalExceptionHandler implements HandlerExceptionResolver {
    16.  
    17.     @Override
    18.     public ModelAndView resolveException(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) {
    19.         ModelAndView mv=new ModelAndView();
    20.         mv.setViewName("error");
    21.         if(e instanceof GlobalException){
    22.             GlobalException globalException = (GlobalException) e;
    23.             mv.addObject("ex",globalException);
    24.             mv.addObject("msg","全局异常");
    25.         }else if(e instanceof RuntimeException){
    26.             RuntimeException runtimeException = (RuntimeException) e;
    27.             mv.addObject("ex",runtimeException.getMessage());
    28.             mv.addObject("msg","运行时异常");
    29.         }
    30.         return mv;
    31.     }
    32. }
    33.

    2.3;使用@ControllerAdvice+@ExceptionHandler实现全局异常

    1. package com.xbb.ssm.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 冰冰
    9.  * @create 2022-08-23 21:50
    10.  */
    11. @ControllerAdvice
    12. public class GlobalExceptionResolver {
    13.     @ExceptionHandler
    14.     public ModelAndView handler(Exception e){
    15.         ModelAndView mv = new ModelAndView();
    16.         mv.setViewName("error");
    17.         if(e instanceof GlobalException){
    18.             GlobalException globalException = (GlobalException) e;
    19.             mv.addObject("ex",globalException.getMessage());
    20.             mv.addObject("msg","全局异常");
    21.         }else if(e instanceof RuntimeException){
    22.             RuntimeException runtimeException = (RuntimeException) e;
    23.             mv.addObject("ex",runtimeException.getMessage());
    24.             mv.addObject("msg","运行时异常..");
    25.         }
    26.         return mv;
    27.     }
    28. }
    29.

    2.4全局异常处理JSON返回

    1. package com.xbb.ssm.exception;
    2.  
    3. import org.springframework.web.bind.annotation.ExceptionHandler;
    4. import org.springframework.web.bind.annotation.RestControllerAdvice;
    5.  
    6. import java.util.HashMap;
    7. import java.util.Map;
    8.  
    9. /**
    10.  * @author 冰冰
    11.  * @create 2022-08-23 21:55
    12.  */
    13. @RestControllerAdvice
    14. public class GlobalExceptionJsonResolver {
    15.     @ExceptionHandler
    16.     public Map handler(Exception e){
    17.         Map map = new HashMap();
    18.         if(e instanceof GlobalException){
    19.             GlobalException globalException = (GlobalException) e;
    20.             map.put("ex",globalException.getMessage());
    21.             map.put("msg","全局异常");
    22.         }else if(e instanceof RuntimeException){
    23.             RuntimeException runtimeException = (RuntimeException) e;
    24.             map.put("ex",runtimeException.getMessage());
    25.             map.put("msg","运行时异常");
    26.         }
    27.         return map;
    28.     }
    29. }
    30.

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  • 原文地址：https://blog.csdn.net/m0_68211831/article/details/126492281