异常处理-异常处理器 01

一、

案例、
结构

环境
1、pom.xml

<!--    servlet规范-->
<dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>javax.servlet-api</artifactId>
    <version>3.1.0</version>
    <scope>provided</scope>
</dependency>
<!--   jsp -->
<dependency>
    <groupId>javax.servlet.jsp</groupId>
    <artifactId>jsp-api</artifactId>
    <version>2.1</version>
    <scope>provided</scope>
</dependency>

<!--      spring-->
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-webmvc</artifactId>
    <version>5.1.9.RELEASE</version>
</dependency>
<!-- spring Mvc-->
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-context</artifactId>
    <version>5.1.9.RELEASE</version>
</dependency>
<!-- spring Web-->
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-web</artifactId>
    <version>5.1.9.RELEASE</version>
</dependency>
<!--json的3个坐标-->
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-core</artifactId>
    <version>2.9.0</version>
</dependency>
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.9.0</version>
</dependency>
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-annotations</artifactId>
    <version>2.9.0</version>
</dependency>

2、controller层

3、实现HandlerExceptionResolver接口且声明为bean

4、spring-mvc.xml

5、web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
          http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
         version="3.0">
    <!--用于解决中文乱码-->
    <filter>
        <filter-name>CharacterEncodingFilter</filter-name>
        <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>UTF-8</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>CharacterEncodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
    <!--拦截-->
    <servlet>
        <servlet-name>DispatcherServlet</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath*:spring-mvc.xml</param-value>
        </init-param>
    </servlet>
    <servlet-mapping>
        <servlet-name>DispatcherServlet</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>

</web-app>

6、ajax.jsp

<%@page pageEncoding="UTF-8" language="java" contentType="text/html;UTF-8" %>

<a href="javascript:void(0);" id="testException">访问springmvc后台controller,传递Json格式POJO</a><br/>

<%--本地下载的jquery位置--%>
<script type="text/javascript" src="${pageContext.request.contextPath}/js/jquery-3.3.1.main.js"></script>
<script type="text/javascript">
    $(function () {
        // 为id="testAjax"的组件绑定点击事件
        $("#testException").click(function () {
            //发送异步调用
            $.ajax({
                //请求正文的MIME类型
                contentType: "application/json",
                //请求方式:
                type: "POST",
                //请求的地址
                url: "save",
                //请求参数（也就是请求内容)
                data: '{"name":"jock","age":"39"}',
                //响应正文类型
                dataType: "text",
                //回调函数
                success: function (data) {
                    alert(data);
                }
            });
        });
        //    -----------------------------
    })
</script>

7、测试
现在只需要在controller层的save方法弄点异常就行了