自定义好处：

1、统一风格，方便定位问题；

2、方便控制异常流程。

第一步：创建一个自定义异常类，继承自RuntimeException，如下

package com.vlihub.common.exception;

import com.vlihub.common.enums.Codes;

/**

* 创建人： 537974(韦立)

* 创建时间: 2020-11-26 16:27

*/

public class VlihubException extends RuntimeException {

private Codes codes;

public VlihubException() {

super();

}

public VlihubException(String msg) {

super(msg);

this.codes = Codes.ERROR;

}

public VlihubException(Throwable e) {

super(e);

this.codes = Codes.ERROR;

}

public VlihubException(Codes codes) {

super(codes.getMsg());

this.codes = codes;

}

public VlihubException(Codes codes, String msg) {

super(msg);

this.codes = codes;

}

public Codes getCodes() {

return this.codes;

}

}

上面简单使用一个枚举型作为统一的返回编码。

第二步：处理异常，如下

package com.vlihub.common.exception;

import com.vlihub.common.configs.AppMailConfig;

import com.vlihub.common.enums.Codes;

import com.vlihub.common.helper.MailHelper;

import com.vlihub.common.model.vo.BaseResult;

import com.vlihub.common.model.vo.MailInfo;

import org.springframework.dao.DuplicateKeyException;

import org.springframework.web.bind.annotation.ControllerAdvice;

import org.springframework.web.bind.annotation.ExceptionHandler;

import org.springframework.web.bind.annotation.ResponseBody;

import javax.annotation.Resource;

import java.io.PrintWriter;

import java.io.StringWriter;

/**

* 创建人： 537974(韦立)

* 创建时间: 2020-11-26 16:31

*/

@ControllerAdvice

@ResponseBody

public class VlihubExceptionHandler {

@Resource

private MailHelper mailHelper;

@Resource

private AppMailConfig appMailConfig;

@ExceptionHandler(value = Exception.class)

public BaseResult exceptionHandler(Exception e) {

e.printStackTrace();

Thread th = new Thread(() -> sendErrorMail(e));

th.start();

if (e instanceof VlihubException) {

Codes code = ((VlihubException) e).getCodes();

return BaseResult.builder()

.code(code.getCode())

.title(Codes.ERROR.getMsg())

.message(e.getMessage())

.type(Codes.ERROR.toString().toLowerCase())

.build();

} else if (e instanceof NullPointerException) {

return BaseResult.error(e.getMessage(), Codes.ERROR_NULL_POINTER);

} else if (e instanceof DuplicateKeyException) {

return BaseResult.error(e.getMessage(), Codes.ERROR_SQL);

} else if (e instanceof IndexOutOfBoundsException) {

return BaseResult.error(e.getMessage(), Codes.ERROR_IDX_OUT_OF_BOUNDS);

} else if (e instanceof IllegalArgumentException) {

return BaseResult.error(e.getMessage(), Codes.ERROR_ILLEGAL_ARGUMENT);

}

return BaseResult.error(e.getMessage());

}

private void sendErrorMail(Exception e) {

MailInfo mailInfo = new MailInfo();

mailInfo.setTo(appMailConfig.getWarningTos());

mailInfo.setFrom(appMailConfig.getDefaultFrom());

mailInfo.setSubject("迈极集团-异常");

StringWriter sw = new StringWriter();

e.printStackTrace(new PrintWriter(sw));

mailInfo.setText(sw.getBuffer().toString());

mailInfo.setIsHtml(true);

mailHelper.sendMail(mailInfo);

}

}

上面对异常做了简单处理，并且异常出现后发送邮件通知。