[Improvement][Master] Construct processInstance may NPE when master handling command (#12056)

* [Improvement][Master] Construct processInstance may NPE when master handling command

* use an enpty map

Co-authored-by: xuhaihui <xuhaihui@cmss.chinamobile.com>

dolphinscheduler-service/src/main/java/org/apache/dolphinscheduler/service/process/ProcessServiceImpl.java

@@ -169,6 +169,7 @@ import com.fasterxml.jackson.databind.node.ObjectNode;
 import com.google.common.base.Joiner;
 import com.google.common.base.Strings;
 import com.google.common.collect.Lists;
+
 import io.micrometer.core.annotation.Counted;
 
 /**
@@ -938,6 +939,9 @@ public class ProcessServiceImpl implements ProcessService {
             throw new IllegalArgumentException("Cannot find the process definition for this workflowInstance");
         }
         Map<String, String> cmdParam = JSONUtils.toMap(command.getCommandParam());
+        if(cmdParam == null){
+            cmdParam = new HashMap<>();
+        }
         int processInstanceId = command.getProcessInstanceId();
         if (processInstanceId == 0) {
             processInstance = generateNewProcessInstance(processDefinition, command, cmdParam);
@@ -947,7 +951,7 @@ public class ProcessServiceImpl implements ProcessService {
                 return null;
             }
         }
-        if (cmdParam != null) {
+
         CommandType commandTypeIfComplement = getCommandTypeIfComplement(processInstance, command);
         // reset global params while repeat running is needed by cmdParam
         if (commandTypeIfComplement == CommandType.REPEAT_RUNNING) {
@@ -965,18 +969,19 @@ public class ProcessServiceImpl implements ProcessService {
             processInstance.getScheduleTime(), timezoneId);
         processInstance.setGlobalParams(globalParams);
         processInstance.setProcessDefinition(processDefinition);
-        }
+
         // reset command parameter
         if (processInstance.getCommandParam() != null) {
             Map<String, String> processCmdParam = JSONUtils.toMap(processInstance.getCommandParam());
+            Map<String, String> finalCmdParam = cmdParam;
             processCmdParam.forEach((key, value) -> {
-                if (!cmdParam.containsKey(key)) {
+                if (!finalCmdParam.containsKey(key)) {
-                    cmdParam.put(key, value);
+                    finalCmdParam.put(key, value);
                 }
             });
         }
         // reset command parameter if sub process
-        if (cmdParam != null && cmdParam.containsKey(Constants.CMD_PARAM_SUB_PROCESS)) {
+        if (cmdParam.containsKey(Constants.CMD_PARAM_SUB_PROCESS)) {
             processInstance.setCommandParam(command.getCommandParam());
         }
         if (Boolean.FALSE.equals(checkCmdParam(command, cmdParam))) {
@@ -1027,7 +1032,7 @@ public class ProcessServiceImpl implements ProcessService {
                     initTaskInstance(this.findTaskInstanceById(taskId));
                 }
                 cmdParam.put(Constants.CMD_PARAM_RECOVERY_START_NODE_STRING,
-                        String.join(",", convertIntListToString(stopNodeList)));
+                    String.join(Constants.COMMA, convertIntListToString(stopNodeList)));
                 processInstance.setCommandParam(JSONUtils.toJsonString(cmdParam));
                 processInstance.setRunTimes(runTime + 1);
                 break;