add retMap null check for AlertSender (#1796)

* fix bug: zk hasTask method NPE

* add retMap null check for AlertSender

dolphinscheduler-alert/src/main/java/org/apache/dolphinscheduler/alert/runner/AlertSender.java

@@ -31,6 +31,7 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
 
@@ -72,9 +73,7 @@ public class AlertSender{
             String receivers = alert.getReceivers();
             if (StringUtils.isNotEmpty(receivers)){
                 String[] splits = receivers.split(",");
-                for (String receiver : splits){
-                    receviersList.add(receiver);
-                }
+                receviersList.addAll(Arrays.asList(splits));
             }
 
             // copy list
@@ -86,9 +85,7 @@ public class AlertSender{
 
             if (StringUtils.isNotEmpty(receiversCc)){
                 String[] splits = receiversCc.split(",");
-                for (String receiverCc : splits){
-                    receviersCcList.add(receiverCc);
-                }
+                receviersCcList.addAll(Arrays.asList(splits));
             }
 
             if (CollectionUtils.isEmpty(receviersList) && CollectionUtils.isEmpty(receviersCcList)) {
@@ -106,7 +103,13 @@ public class AlertSender{
                 alert.setInfo(retMaps);
             }
 
-            boolean flag = Boolean.parseBoolean(String.valueOf(retMaps.get(Constants.STATUS)));
+            //send flag
+            boolean flag = false;
+
+            if (null != retMaps) {
+                flag = Boolean.parseBoolean(String.valueOf(retMaps.get(Constants.STATUS)));
+            }
+
             if (flag) {
                 alertDao.updateAlert(AlertStatus.EXECUTION_SUCCESS, "execution success", alert.getId());
                 logger.info("alert send success");
@@ -121,8 +124,10 @@ public class AlertSender{
                 }
 
             } else {
-                alertDao.updateAlert(AlertStatus.EXECUTION_FAILURE, String.valueOf(retMaps.get(Constants.MESSAGE)), alert.getId());
-                logger.info("alert send error : {}", String.valueOf(retMaps.get(Constants.MESSAGE)));
+                if (null != retMaps) {
+                    alertDao.updateAlert(AlertStatus.EXECUTION_FAILURE, String.valueOf(retMaps.get(Constants.MESSAGE)), alert.getId());
+                    logger.info("alert send error : {}", retMaps.get(Constants.MESSAGE));
+                }
             }
         }
 

dolphinscheduler-alert/src/main/java/org/apache/dolphinscheduler/alert/utils/ExcelUtils.java

@@ -16,6 +16,7 @@
  */
 package org.apache.dolphinscheduler.alert.utils;
 
+import org.apache.dolphinscheduler.common.utils.CollectionUtils;
 import org.apache.poi.hssf.usermodel.HSSFCell;
 import org.apache.poi.hssf.usermodel.HSSFRow;
 import org.apache.poi.hssf.usermodel.HSSFSheet;
@@ -47,7 +48,7 @@ public class ExcelUtils {
         //The JSONUtils.toList has been try catch ex
         itemsList = JSONUtils.toList(content, LinkedHashMap.class);
 
-        if (itemsList == null || itemsList.size() == 0){
+        if (CollectionUtils.isEmpty(itemsList)){
             logger.error("itemsList is null");
             throw new RuntimeException("itemsList is null");
         }

dolphinscheduler-alert/src/main/java/org/apache/dolphinscheduler/alert/utils/MailUtils.java

@@ -25,7 +25,6 @@ import org.apache.dolphinscheduler.common.utils.CollectionUtils;
 import org.apache.dolphinscheduler.common.utils.StringUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-import org.springframework.util.ResourceUtils;
 
 import javax.mail.*;
 import javax.mail.internet.*;
@@ -33,7 +32,6 @@ import java.io.*;
 import java.util.*;
 
 
-
 /**
  * mail utils
  */
@@ -320,12 +318,12 @@ public class MailUtils {
     public static void deleteFile(File file){
         if(file.exists()){
             if(file.delete()){
-                logger.info("delete success:"+file.getAbsolutePath()+file.getName());
+                logger.info("delete success: {}",file.getAbsolutePath() + file.getName());
             }else{
-                logger.info("delete fail"+file.getAbsolutePath()+file.getName());
+                logger.info("delete fail: {}", file.getAbsolutePath() + file.getName());
             }
         }else{
-            logger.info("file not exists:"+file.getAbsolutePath()+file.getName());
+            logger.info("file not exists: {}", file.getAbsolutePath() + file.getName());
         }
     }