SpringBoot入門二十一,全局異常處理

一共兩個文件,一個處理全局異常,保存信息到日誌,另外一個負責返回異常信息給接口,只要將其文件添加到項目中,無需再做其他配置即可

1. MyExceptionHandler.java 全局異常處理類

如果多個異常處理類,需要在全局異常處理類(本類)之前執行,請添加:

import org.springframework.core.Ordered;
import org.springframework.core.annotation.Order;

// 只要保證比Ordered.LOWEST_PRECEDENCE 小就可以了
@Order(Ordered.LOWEST_PRECEDENCE - 1)

優先執行此類,這裏不好抓取404、403等錯誤信息
getMaps()請參考獲取request中傳遞過來的參數信息
getHeaders()請參考獲取request中傳遞過來的header信息
代碼如下：

import java.util.Enumeration;
import java.util.HashMap;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;

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

/**
 * <h5>描述:全局異常處理類</h5>
 * 優先執行此異常處理類
 *  
 */
@ControllerAdvice
public class MyExceptionHandler {
    private final Logger log = LoggerFactory.getLogger(getClass());

    @ExceptionHandler(value =Exception.class)
    public String exceptionHandler(HttpServletRequest request, Exception e){
        Map<String, Object> paramsMap = getMaps(request);
        Map<String, Object> headersMap = getHeaders(request);

        String requestUri = request.getAttribute("org.springframework.web.servlet.HandlerMapping.lookupPath").toString();
        log.error("請求[{}]發生[{}]異常\r\n參數[{}]\r\nheader[{}]", requestUri,e.getMessage(),paramsMap,headersMap, e);

        // 返回錯誤信息,交給其他異常處理類處理
        return e.getMessage();
    }

    // =================== private method ===================

    /**
     * <h5>功能:獲取從request中傳遞過來的參數信息</h5>
     * 
     * @return Map<String, Object>
     */
    private Map<String, Object> getMaps(HttpServletRequest request){
        Map<String, Object> paramMap = new HashMap<String, Object>();
        Enumeration<String> enume = request.getParameterNames();
        while (enume.hasMoreElements()) {
            String key = (String) enume.nextElement();
            String[] values = request.getParameterValues(key);
            paramMap.put(key, values.length == 1 ? request.getParameter(key).trim() : values);
        }

        return paramMap;
    }

    /**
     * <h5>功能: 獲取從request中傳遞過來的header信息</h5>
     * 
     * @return Map<String, Object>
     */
    private Map<String, Object> getHeaders(HttpServletRequest request) {
        Map<String, Object> headerMap = new HashMap<String, Object>();
        Enumeration<?> er = request.getHeaderNames();//獲取請求頭的所有name值
        String headerName;
        while(er.hasMoreElements()){
            headerName = er.nextElement().toString();
            headerMap.put(headerName, request.getHeader(headerName));
        }

        return headerMap;
    }
}

2. MyErrorController.java 全局請求錯誤信息處理類

後執行此類,此類可以有效抓取,404、403等信息，代碼如下：

import javax.servlet.http.HttpServletRequest;

import org.springframework.boot.web.servlet.error.ErrorController;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import com.alibaba.fastjson.JSONObject;
import com.jnxj.common.vo.MessageBean;

/**
 * <h5>描述:全局錯誤信息處理</h5>
 *  執行完異常處理類之後執行此類
 */
@RestController
public class MyErrorController implements ErrorController {

    @Override
    public String getErrorPath() {
        return "/error";
    }

    @RequestMapping("/error")
    public String handleError(HttpServletRequest request) {
        String message;
        // 獲取statusCode:401,404,500
        Integer statusCode = (Integer) request.getAttribute("javax.servlet.error.status_code");
        if (statusCode == 400) {
            message = "語義有誤,當前請求無法被服務器理解或請求參數有誤";
        } else if (statusCode == 401) {
            message = "當前請求需要用戶驗證";
        } else if (statusCode == 403) {
            message = "權限不足";
        } else if (statusCode == 404) {
            message = "請求的資源不存在";
        } else {
            message = "系統不小心生病了,正在緊急修復中,請耐心等候...o(╥﹏╥)o";
        }

        MessageBean messageBean = new MessageBean();
        messageBean.setCode(statusCode.toString());
        messageBean.setMessage(message);
        return JSONObject.toJSONString(messageBean);
    }
}