java统一异常处理

1.建一个异常捕捉类

package com.atguigu.commonutils;

import java.io.IOException;
import java.io.PrintWriter;
import java.io.StringWriter;

public class ExceptionUtil {
    public static String getMessage(Exception e) {
        StringWriter sw = null;
        PrintWriter pw = null;
        try {
            sw = new StringWriter();
            pw = new PrintWriter(sw);
            // 将出错的栈信息输出到printWriter中
            e.printStackTrace(pw);
            pw.flush();
            sw.flush();
        } finally {
            if (sw != null) {
                try {
                    sw.close();
                } catch (IOException e1) {
                    e1.printStackTrace();
                }
            }
            if (pw != null) {
                pw.close();
            }
        }
        return sw.toString();
    }
}

 

2.编写统一异常处理类，全局异常处理，自定义异常处理

package com.atguigu.servicebase.config.exceptionhandler;

import com.atguigu.commonutils.ExceptionUtil;
import com.atguigu.commonutils.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;

@ControllerAdvice
@Slf4j
public class GlobalExceptionHandler {

    //指定出现什么异常出现这个方法
    @ExceptionHandler(Exception.class)
    @ResponseBody //为了能够返回数据
    public R error(Exception e) {
        e.printStackTrace();

        return R.error().message("执行了全局异常处理...");
    }

    //特定异常处理
    @ExceptionHandler(ArithmeticException.class)
    @ResponseBody
    public R error(ArithmeticException e) {
        e.printStackTrace();

        return R.error().message("执行了ArithmeticException异常处理...");
    }

    //自定义异常处理
    @ExceptionHandler(GuliException.class)
    @ResponseBody
    public R error(GuliException e) {
        e.printStackTrace();

        log.error(ExceptionUtil.getMessage(e));

        return R.error().code(e.getCode()).message(e.getMsg());
    }
    //调用方法
//    try {
//        int i = 10/0;
//    } catch (Exception e) {
//        throw new GuliException(20001,"分母不能为0");
//    }
}

　

自定义异常处理的类，上面是方法

package com.atguigu.servicebase.config.exceptionhandler;

import io.swagger.annotations.ApiModelProperty;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@AllArgsConstructor
@NoArgsConstructor
public class GuliException extends RuntimeException {

    @ApiModelProperty(value = "状态码")
    private Integer code;

    private String msg;

    @Override
    public String toString() {
        return "GuliException{" +
        "message=" + this.getMsg() +
        ", code=" + code +
        '}';
    }
}