三、全局异常Exception的配置

一、首先自定义一个异常拦截器

　1、拦截异常所有 及拦截 Exception异常

package com.cg.demo.exception;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;

import javax.servlet.http.HttpServletRequest;
import java.util.HashMap;
import java.util.Map;

/**
 * 说明:
 *
 * @auther panhh
 * @date 2019/7/12 9:37
 */
@RestControllerAdvice
public class GlobalExceptionHandler {

    //捕获所有异常 获取内部异常处理类：Exception
    private static final Logger LOG = LoggerFactory.getLogger(GlobalExceptionHandler.class);

    @ExceptionHandler(value = Exception.class)
    public Map excption(Exception e, HttpServletRequest request){
        
        String eMessage = e.getMessage();
        StringBuffer url = request.getRequestURL();
        System.out.println("ErrorMsg-->"+eMessage);
        System.out.println("url-->"+url);

        //打印日志
        LOG.error("错误信息-->"+eMessage+"===请求链接--->"+url);
        
        HashMap<Object, Object> hashMap = new HashMap<>();
        hashMap.put("msg",eMessage);
        hashMap.put("url",url);
        
        return hashMap;
    }
}

2、效果测试

　　@Controller

public class ExcTestController {

    @RequestMapping("/test")
    @ResponseBody
    public String test(){
        int a = 4/0;
        return "test";
    }
}

2、拦截器效果（控制台打印）
　

ErrorMsg-->/ by zero
url-->http://localhost:8080/test
2019-07-12 09:59:11.124 ERROR 10096 --- [nio-8080-exec-5] c.c.d.exception.GlobalExceptionHandler : 错误信息-->/ by zero===请求链接--->http://localhost:8080/test

　3、页面返回内容：

　　{"msg":"/ by zero","url":"http://localhost:8080/test"}

二、自定义一个异常,自定义异常需要自己抛出

　1、自定义一个异常

package com.cg.demo.exception;

import lombok.Data;
import lombok.ToString;

/**
 * 说明:
 *
 * @auther panhh
 * @date 2019/7/12 9:36
 */
@Data
@ToString
public class GlobalException extends RuntimeException {

    private String msg;
    private Integer code;

    public GlobalException(String msg, Integer code) {
        this.msg = msg;
        this.code = code;
    }
}

2、异常拦截器拦截方法
　　

private static final Logger LOG = LoggerFactory.getLogger(GlobalExceptionHandler.class);

@ExceptionHandler(value = GlobalException.class)
public Map myExcption(GlobalException e, HttpServletRequest request){

    String eMessage = e.getMsg();
    Integer code = e.getCode();
    StringBuffer url = request.getRequestURL();
    System.out.println("ErrorMsg-->"+eMessage);
    System.out.println("url-->"+url);

    //打印日志
    LOG.error("错误信息-->"+eMessage+"===请求链接--->"+url+"错误状态码--->"+code);

    HashMap<Object, Object> hashMap = new HashMap<>();
    hashMap.put("msg",eMessage);
    hashMap.put("code",code);
    hashMap.put("url",url);

    return hashMap;
}

3、测试
（1）　　

@Controller
public class ExcTestController {

    @RequestMapping("/test")
    @ResponseBody
    public String test() {
        throw new GlobalException("抛出一个自定义异常",4001);
    }
}

（2）拦截器打印内容
　　

　　ErrorMsg-->抛出一个自定义异常
　　url-->http://localhost:8080/test
　　2019-07-12 10:14:01.155 ERROR 10132 --- [nio-8080-exec-1] c.c.d.exception.GlobalExceptionHandler : 错误信息-->抛出一个自定义异常===请求链接--->http://localhost:8080/test错误状态码--->4001

　（3）前台页面返回

　　{"msg":"抛出一个自定义异常","code":4001,"url":"http://localhost:8080/test"}

三、补充，可以自定义一个返回信息枚举类

　　1、自定义一个枚举类

　　　　

package com.cg.demo.exception;

import lombok.Data;

/**
 * 说明:
 *
 * @auther panhh
 * @date 2019/7/12 10:21
 */
public enum  ResponseEnum {

    SUCCESS(200,"操作成功"),
    ERROR(400,"操作失败"),
    ;

    private Integer code;
    private String msg;

    ResponseEnum(Integer code, String msg) {
        this.code = code;
        this.msg = msg;
    }

    public Integer getCode() {
        return code;
    }

    public void setCode(Integer code) {
        this.code = code;
    }

    public String getMsg() {
        return msg;
    }

    public void setMsg(String msg) {
        this.msg = msg;
    }
}

2、自定义异常类修改 GlobalException为
　　　　

package com.cg.demo.exception;

import lombok.Data;
import lombok.ToString;

/**
 * 说明:
 *
 * @auther panhh
 * @date 2019/7/12 9:36
 */
@Data
@ToString
public class GlobalException extends RuntimeException {
    
    private ResponseEnum responseEnum;

    //添加一个构造函数
    public GlobalException(ResponseEnum re){
        this.responseEnum = re;
    }
}

3、异常拦截器拦截方法修改为
　　

private static final Logger LOG = LoggerFactory.getLogger(GlobalExceptionHandler.class);

@ExceptionHandler(value = GlobalException.class)
public Map myExcption(GlobalException e, HttpServletRequest request){

    ResponseEnum re = e.getResponseEnum();
    String eMessage = re.getMsg();
    Integer code = re.getCode();
    StringBuffer url = request.getRequestURL();

    System.out.println("ErrorMsg-->"+eMessage);
    System.out.println("code-->"+code);
    System.out.println("url-->"+url);

    //打印日志
    LOG.error("错误信息-->"+eMessage+"===请求链接--->"+url+"错误状态码--->"+code);

    HashMap<Object, Object> hashMap = new HashMap<>();
    hashMap.put("msg",eMessage);
    hashMap.put("code",code);
    hashMap.put("url",url);

    return hashMap;
}

4、异常演示
　　（1）、抛出一个异常
　　　　

@Controller
public class ExcTestController {

    @RequestMapping("/test")
    @ResponseBody
    public String test() {
        throw new GlobalException(ResponseEnum.ERROR);
    }
}
　　
（2）、拦截器方法打印的内容
　　

　　　　ErrorMsg-->操作失败
　　　　code-->400
　　　　url-->http://localhost:8080/test
　　　　019-07-12 10:31:06.281 ERROR 4764 --- [nio-8080-exec-1] c.c.d.exception.GlobalExceptionHandler : 错误信息-->操作失败===请求链接--->http://localhost:8080/test错误状态码--->400

　　（3）、前台页面返回内容　　　　　

　　　　　　{"msg":"操作失败","code":400,"url":"http://localhost:8080/test"}

四、pom.xml文件

　　

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.6.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.cg.demo</groupId>
    <artifactId>some_demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>some_demo</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
    </properties>

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

        <dependency>
            <groupId>org.postgresql</groupId>
            <artifactId>postgresql</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <!-- swagger2 -->
        <dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-swagger2</artifactId>
            <version>2.9.2</version>
        </dependency>

        <!-- swagger-ui -->
        <dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-swagger-ui</artifactId>
            <version>2.9.2</version>
        </dependency>

        <!--Aop-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-aop</artifactId>
        </dependency>
        <!--mybatis-->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.3.2</version>
        </dependency>
    </dependencies>

五、本文到这里就结束了，奋斗越久越划算，工资变成零花钱 ，希望你不忘初心，继续努力哈！