fix(办公管理): 修复已办任务撤回操作操作失败问题（https://gitee.com/KonBAI-Q/ruoyi-flowable-plus/issues/I61V7N）

ruoyi-flowable/src/main/java/com/ruoyi/flowable/common/enums/FlowComment.java

@@ -16,7 +16,8 @@ public enum FlowComment {
     REJECT("3", "驳回"),
     DELEGATE("4", "委派"),
     TRANSFER("5", "转办"),
-    STOP("6", "终止");
+    STOP("6", "终止"),
+    REVOKE("7", "撤回");
 
     /**
      * 类型

ruoyi-flowable/src/main/java/com/ruoyi/flowable/utils/ModelUtils.java

@@ -6,8 +6,7 @@ import org.flowable.bpmn.model.Process;
 import org.flowable.bpmn.model.*;
 import org.flowable.common.engine.impl.util.io.StringStreamSource;
 
-import java.util.ArrayList;
-import java.util.Collection;
+import java.util.*;
 
 /**
  * @author KonBAI
@@ -37,6 +36,35 @@ public class ModelUtils {
         return bpmnXMLConverter.convertToXML(bpmnModel);
     }
 
+    /**
+     * 根据节点，获取入口连线
+     *
+     * @param source 起始节点
+     * @return 入口连线列表
+     */
+    public static List<SequenceFlow> getElementIncomingFlows(FlowElement source) {
+        List<SequenceFlow> sequenceFlows = new ArrayList<>();
+        if (source instanceof FlowNode) {
+            sequenceFlows = ((FlowNode) source).getIncomingFlows();
+        }
+        return sequenceFlows;
+    }
+
+
+    /**
+     * 根据节点，获取出口连线
+     *
+     * @param source 起始节点
+     * @return 出口连线列表
+     */
+    public static List<SequenceFlow> getElementOutgoingFlows(FlowElement source) {
+        List<SequenceFlow> sequenceFlows = new ArrayList<>();
+        if (source instanceof FlowNode) {
+            sequenceFlows = ((FlowNode) source).getOutgoingFlows();
+        }
+        return sequenceFlows;
+    }
+
     /**
      * 获取开始节点
      *
@@ -141,4 +169,46 @@ public class ModelUtils {
         }
         return allElements;
     }
+
+    /**
+     * 查找起始节点下一个用户任务列表列表
+     * @param source 起始节点
+     * @return 结果
+     */
+    public static List<UserTask> findNextUserTasks(FlowElement source) {
+        return findNextUserTasks(source, null, null);
+    }
+
+    /**
+     * 查找起始节点下一个用户任务列表列表
+     * @param source 起始节点
+     * @param hasSequenceFlow 已经经过的连线的 ID，用于判断线路是否重复
+     * @param userTaskList 用户任务列表
+     * @return 结果
+     */
+    public static List<UserTask> findNextUserTasks(FlowElement source, Set<String> hasSequenceFlow, List<UserTask> userTaskList) {
+        hasSequenceFlow = Optional.ofNullable(hasSequenceFlow).orElse(new HashSet<>());
+        userTaskList = Optional.ofNullable(userTaskList).orElse(new ArrayList<>());
+        // 获取出口连线
+        List<SequenceFlow> sequenceFlows = getElementOutgoingFlows(source);
+        if (!sequenceFlows.isEmpty()) {
+            for (SequenceFlow sequenceFlow : sequenceFlows) {
+                // 如果发现连线重复，说明循环了，跳过这个循环
+                if (hasSequenceFlow.contains(sequenceFlow.getId())) {
+                    continue;
+                }
+                // 添加已经走过的连线
+                hasSequenceFlow.add(sequenceFlow.getId());
+                FlowElement targetFlowElement = sequenceFlow.getTargetFlowElement();
+                if (targetFlowElement instanceof UserTask) {
+                    // 若节点为用户任务，加入到结果列表中
+                    userTaskList.add((UserTask) targetFlowElement);
+                } else {
+                    // 若节点非用户任务，继续递归查找下一个节点
+                    findNextUserTasks(targetFlowElement, hasSequenceFlow, userTaskList);
+                }
+            }
+        }
+        return userTaskList;
+    }
 }