• SpringMVC对JSON的支持& SpringMVC的全局异常处理

    目录

    一、SpringMVC对JSON的支持

    1、JOSN的各种场景

    2、pom依赖

    3、Springmvc.xml配置

    4、后台代码

    4.1ClazzBiz

    4.2 ClazzBizImpl

    4.3 ClazzMapper

    4.4 ClazzMapper.xml

    4.5 JsonController

    5、前台测试

      index.jsp

    二、SpringMVC 的全局异常处理

    1、SpringMVC自带的简单异常处理器

    2、通过HandlerExceptionResovler接口实现全局异常

    2.1GlobalException

    2.2 GlobalException

    2.3 controller层

    3、使用@ControllerAdvice+@ExceptionHandler实现全局异常

    4、全局异常处理JSON返回

    一、SpringMVC对JSON的支持

    1、JOSN的各种场景

    1.1返回List
    1.2返回List
    1.3返回T
    1.4返回Map
    1.5返回混合

    2、pom依赖

    1.  <dependency>
    2.       <groupId>com.fasterxml.jackson.coregroupId>
    3.       <artifactId>jackson-databindartifactId>
    4.       <version>2.9.3version>
    5.     dependency>
    6.     <dependency>
    7.       <groupId>com.fasterxml.jackson.coregroupId>
    8.       <artifactId>jackson-coreartifactId>
    9.       <version>2.9.3version>
    10.     dependency>
    11.     <dependency>
    12.       <groupId>com.fasterxml.jackson.coregroupId>
    13.       <artifactId>jackson-annotationsartifactId>
    14.       <version>2.9.3version>
    15.     dependency>
    16.

     3、Springmvc.xml配置

    1. <bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter">
    2.         <property name="messageConverters">
    3.             <list>
    4.                 <ref bean="mappingJackson2HttpMessageConverter"/>
    5.             list>
    6.         property>
    7.     bean>
    8.     <bean id="mappingJackson2HttpMessageConverter"
    9.           class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
    10.         
    11.         <property name="supportedMediaTypes">
    12.             <list>
    13.                 <value>text/html;charset=UTF-8value>
    14.                 <value>text/json;charset=UTF-8value>
    15.                 <value>application/json;charset=UTF-8value>
    16.             list>
    17.         property>
    18.     bean>
    19.

    4、后台代码

    4.1ClazzBiz

    1. package com.zsx.ssm.biz;
    2.  
    3. import com.zsx.ssm.model.Clazz;
    4. import com.zsx.ssm.util.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.     int updateByPrimaryKeySelective(Clazz record);
    19.  
    20.     int updateByPrimaryKey(Clazz record);
    21.  
    22.     List listPager(Clazz record, PageBean pageBean);
    23.  
    24.     List listMapPager(Clazz record, PageBean pageBean);
    25. }

    4.2 ClazzBizImpl

    1. package com.zsx.ssm.biz.impl;
    2.  
    3. import com.zsx.ssm.biz.ClazzBiz;
    4. import com.zsx.ssm.mapper.ClazzMapper;
    5. import com.zsx.ssm.model.Clazz;
    6. import com.zsx.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 zsx
    15.  * @site 155954····
    16.  * @company 交换余生
    17.  * @create 2022--08--17  18:23
    18.  */
    19.  
    20. @Service
    21. public class ClazzBizImpl implements ClazzBiz {
    22.     @Autowired
    23.     private ClazzMapper clazzMapper;
    24.  
    25.     @Override
    26.     public int deleteByPrimaryKey(Integer cid) {
    27.         return clazzMapper.deleteByPrimaryKey(cid);
    28.     }
    29.  
    30.     @Override
    31.     public int insert(Clazz record) {
    32.         return clazzMapper.insert(record);
    33.     }
    34.  
    35.     @Override
    36.     public int insertSelective(Clazz record) {
    37.         return clazzMapper.insertSelective(record);
    38.     }
    39.  
    40.     @Override
    41.     public Clazz selectByPrimaryKey(Integer cid) {
    42.         return clazzMapper.selectByPrimaryKey(cid);
    43.     }
    44.  
    45.     @Override
    46.     public List listPager(Clazz record, PageBean pageBean) {
    47.         return clazzMapper.listPager(record);
    48.     }
    49.  
    50.     @Override
    51.     public List listMapPager(Clazz record, PageBean pageBean) {
    52.         if (true)
    53.             throw new RuntimeException("查询班级信息 异常出现在 ClazzBizImpl.list...");
    54.         return clazzMapper.listMapPager(record,pageBean);
    55.     }
    56.  
    57.     @Override
    58.     public int updateByPrimaryKeySelective(Clazz record) {
    59.         return clazzMapper.updateByPrimaryKeySelective(record);
    60.     }
    61.  
    62.     @Override
    63.     public int updateByPrimaryKey(Clazz record) {
    64.         return clazzMapper.updateByPrimaryKey(record);
    65.     }
    66. }

    4.3 ClazzMapper

    1. package com.zsx.ssm.mapper;
    2.  
    3. import com.zsx.ssm.model.Clazz;
    4. import com.zsx.ssm.util.PageBean;
    5. import org.springframework.stereotype.Repository;
    6.  
    7. import java.util.List;
    8. import java.util.Map;
    9.  
    10. @Repository
    11. public interface ClazzMapper {
    12.     int deleteByPrimaryKey(Integer cid);
    13.  
    14.     int insert(Clazz record);
    15.  
    16.     int insertSelective(Clazz record);
    17.  
    18.     Clazz selectByPrimaryKey(Integer cid);
    19.  
    20.     List listPager(Clazz record);
    21.  
    22.     int updateByPrimaryKeySelective(Clazz record);
    23.  
    24.     int updateByPrimaryKey(Clazz record);
    25.  
    26.     List listMapPager(Clazz record, PageBean pageBean);
    27. }

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

    4.5 JsonController

    1. package com.zsx.ssm.controller;
    2.  
    3. import com.zsx.ssm.biz.ClazzBiz;
    4. import com.zsx.ssm.model.Clazz;
    5. import com.zsx.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. import org.springframework.web.bind.annotation.RestController;
    11.  
    12. import javax.servlet.http.HttpServletRequest;
    13. import java.util.HashMap;
    14. import java.util.List;
    15. import java.util.Map;
    16.  
    17. /**
    18.  * @author zsx
    19.  * @site 155954····
    20.  * @company 交换余生
    21.  * @create 2022--08--22  16:28
    22.  * 注:@RestController = @ResponseBody + @Controller
    23.  */
    24. @ResponseBody
    25. //@Controller
    26. //@RestController
    27. @RequestMapping("/json")
    28. public class JsonController {
    29.     @Autowired
    30.     private ClazzBiz clazzBiz;
    31.  
    32.  
    33.     @RequestMapping("/clzEdit")
    34.     public String clzEdit(){
    35.         System.out.println("JsonController.list");
    36.         return "clzEdit";
    37.     }
    38.  
    39.  
    40.  
    41.     @RequestMapping("/list")
    42.     public List list(HttpServletRequest request ,Clazz clazz){
    43.         PageBean pageBean=new PageBean();
    44.         pageBean.setRequest(request);
    45. //        if (true)
    46. //            throw new RuntimeException("查询班级信息 异常出现在 JsonController.list...");
    47.         return this.clazzBiz.listPager(clazz,pageBean);
    48.     }
    49.  
    50.     @RequestMapping("/listMap")
    51.     public List listMap(HttpServletRequest request , Clazz clazz){
    52.         PageBean pageBean=new PageBean();
    53.         pageBean.setRequest(request);
    54.         return this.clazzBiz.listMapPager(clazz,pageBean);
    55.     }
    56.  
    57.     @RequestMapping("/map")
    58.     public Map map(HttpServletRequest request , Clazz clazz){
    59.         PageBean pageBean=new PageBean();
    60.         pageBean.setRequest(request);
    61.         return this.clazzBiz.listMapPager(clazz,pageBean).get(0);
    62.     }
    63.  
    64.     @RequestMapping("/load")
    65.     public Clazz load(HttpServletRequest request , Clazz clazz){
    66.         PageBean pageBean=new PageBean();
    67.         pageBean.setRequest(request);
    68. //        if(true)
    69. //            throw new RuntimeException("系统繁忙，请参考007");
    70.         return this.clazzBiz.listPager(clazz,pageBean).get(0);
    71.     }
    72.  
    73.     @RequestMapping("/hunhe")
    74.     public Map hunhe(HttpServletRequest request , Clazz clazz){
    75.         PageBean pageBean=new PageBean();
    76.         pageBean.setRequest(request);
    77.         List lst = this.clazzBiz.listPager(clazz, pageBean);
    78.         Map map=new HashMap();
    79.         map.put("lst",lst);
    80.         map.put("pageBean",pageBean);
    81.         return map;
    82.     }
    83.  
    84.  
    85. }

    5、前台测试

      index.jsp

    1. <%--
    2.   Created by IntelliJ IDEA.
    3.   User: Administrator
    4.   Date: 2022/8/22
    5.   Time: 16:48
    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jsontitle>
    12. head>
    13. <body>
    14. <a href="${pageContext.request.contextPath}/json/list">返回List<T>a><hr>
    15. <a href="${pageContext.request.contextPath}/json/listMap">返回List<Map>a><hr>
    16. <a href="${pageContext.request.contextPath}/json/load?cid=1">返回Ta><hr>
    17. <a href="${pageContext.request.contextPath}/json/map?cid=1">返回Mapa><hr>
    18. <a href="${pageContext.request.contextPath}/json/hunhe">返回混合a>
    19. body>
    20. html>

    运行效果：

    二、SpringMVC 的全局异常处理

    1、SpringMVC自带的简单异常处理器

    SpringMVC的配置文件

    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.

    Error.jsp

    1. <%--
    2.   Created by IntelliJ IDEA.
    3.   User: Administrator
    4.   Date: 2022/8/22
    5.   Time: 18:27
    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>错误页面title>
    12. head>
    13. <body>
    14. ${msg} <br>
    15. ${ex}
    16. body>
    17. html>

    2、通过HandlerExceptionResovler接口实现全局异常

    2.1GlobalException

    1. package com.zsx.ssm.exception;
    2.  
    3. /**
    4.  * @author zsx
    5.  * @site 155954····
    6.  * @company 交换余生
    7.  * @create 2022--08--22  18:33
    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 GlobalException

    1. package com.zsx.ssm.exception;
    2.  
    3. /**
    4.  * @author zsx
    5.  * @site 155954····
    6.  * @company 交换余生
    7.  * @create 2022--08--22  18:33
    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. }

    2.3 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 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.     }

    3、使用@ControllerAdvice+@ExceptionHandler实现全局异常

    GlobalExceptionResolver

    1. package com.zsx.ssm.exception;
    2.  
    3. import org.springframework.web.bind.annotation.ControllerAdvice;
    4. import org.springframework.web.bind.annotation.ExceptionHandler;
    5. import org.springframework.web.bind.annotation.RestControllerAdvice;
    6. import org.springframework.web.servlet.HandlerExceptionResolver;
    7. import org.springframework.web.servlet.ModelAndView;
    8.  
    9. import javax.servlet.http.HttpServletRequest;
    10. import javax.servlet.http.HttpServletResponse;
    11.  
    12. /**
    13.  * @author zsx
    14.  * @site 155954····
    15.  * @company 交换余生
    16.  *
    17.  *
    18.  * @create 2022--08--22  18:35
    19.  */
    20.  
    21. @ControllerAdvice
    22. public class GlobalExceptionResovler{
    23.  
    24.     @ExceptionHandler//异常处理器
    25.     public ModelAndView handler(Exception e) {
    26.         ModelAndView mv=new ModelAndView();
    27.         mv.setViewName("error");
    28.         if(e instanceof GlobalException){
    29.             GlobalException exception= (GlobalException) e;
    30.             mv.addObject("ex",exception.getMessage());
    31.             mv.addObject("msg","全局异常，GlobalExceptionResovler错误码501");
    32.         }else if(e instanceof RuntimeException){
    33.             RuntimeException exception= (RuntimeException) e;
    34.             mv.addObject("ex",exception.getMessage());
    35.             mv.addObject("msg","运行异常，GlobalExceptionResovler错误码601");
    36.         }
    37.         return mv;
    38.     }
    39. }

    4、全局异常处理JSON返回

    GlobalExceptionJsonResolver

    1. package com.zsx.ssm.exception;
    2.  
    3. import org.springframework.stereotype.Component;
    4. import org.springframework.stereotype.Controller;
    5. import org.springframework.web.servlet.HandlerExceptionResolver;
    6. import org.springframework.web.servlet.ModelAndView;
    7.  
    8. import javax.servlet.http.HttpServletRequest;
    9. import javax.servlet.http.HttpServletResponse;
    10.  
    11. /**
    12.  * @author zsx
    13.  * @site 155954····
    14.  * @company 交换余生
    15.  *
    16.  *
    17.  * @create 2022--08--22  18:35
    18.  * 处理全局异常的解析器
    19.  */
    20.  
    21. //@Component
    22. public class GlobalHandlerExceptionResovler implements HandlerExceptionResolver {
    23.     @Override
    24.     public ModelAndView resolveException(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) {
    25.         ModelAndView mv=new ModelAndView();
    26.         mv.setViewName("error");
    27.         if(e instanceof GlobalException){
    28.             GlobalException exception= (GlobalException) e;
    29.             mv.addObject("ex",exception.getMessage());
    30.             mv.addObject("msg","全局异常，错误码501");
    31.         }else if(e instanceof RuntimeException){
    32.             RuntimeException exception= (RuntimeException) e;
    33.             mv.addObject("ex",exception.getMessage());
    34.             mv.addObject("msg","运行异常，错误码601");
    35.         }
    36.         return mv;
    37.     }
    38. }

     效果图：

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  • 原文地址：https://blog.csdn.net/weixin_61523879/article/details/126492642