[fix-10596] Workflow relationship cannot be displayed normally (#10625)

Workflow relationship cannot be displayed normally

Closes #10596

Co-authored-by: liudadi <liudi@thinkingdata.cn>
(cherry picked from commit 56d3db0306)

dolphinscheduler-api/src/main/java/org/apache/dolphinscheduler/api/service/impl/WorkFlowLineageServiceImpl.java

@@ -49,6 +49,7 @@ import java.util.stream.Collectors;
 
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;
+import org.springframework.util.CollectionUtils;
 
 /**
  * work flow lineage service impl
@@ -206,6 +207,7 @@ public class WorkFlowLineageServiceImpl extends BaseServiceImpl implements WorkF
                     DependentParameters dependentParameters = JSONUtils.parseObject(taskDefinitionLog.getDependence(), DependentParameters.class);
                     if (dependentParameters != null) {
                         List<DependentTaskModel> dependTaskList = dependentParameters.getDependTaskList();
+                        if (!CollectionUtils.isEmpty(dependTaskList)) {
                             for (DependentTaskModel taskModel : dependTaskList) {
                                 List<DependentItem> dependItemList = taskModel.getDependItemList();
                                 for (DependentItem dependentItem : dependItemList) {
@@ -218,6 +220,7 @@ public class WorkFlowLineageServiceImpl extends BaseServiceImpl implements WorkF
                     }
                 }
             }
+        }
         return sourceWorkFlowCodes;
     }
 }