Activiti6生成實例歷史活動追蹤圖片

　　最近要把Activiti6集成到系統中，遇到了生成追蹤流程圖片的問題，在5.x版本中可以使用歷史流程節點查找ActivityImpl，升級到6.0版本后，pvm包被移除，所以要實現新的圖片生成辦法。本文靈感來自：Activiti6.0.0 跟蹤流程執行情況用紅色框在流程圖上標識路線跟節點

　　生成追蹤流程圖要完成兩件事情：已執行的Activity高亮和已流轉的Flow高亮。

　　以下方法是生成完整的追蹤圖片：

    public InputStream getResourceDiagramInputStream(String id) {
        try {
            // 獲取歷史流程實例
            HistoricProcessInstance historicProcessInstance = historyService.createHistoricProcessInstanceQuery().processInstanceId(id).singleResult();
                        
            // 獲取流程中已經執行的節點，按照執行先后順序排序
            List<HistoricActivityInstance> historicActivityInstanceList = historyService.createHistoricActivityInstanceQuery().processInstanceId(id).orderByHistoricActivityInstanceId().asc().list();
            
            // 構造已執行的節點ID集合
            List<String> executedActivityIdList = new ArrayList<String>();
            for (HistoricActivityInstance activityInstance : historicActivityInstanceList) {
                executedActivityIdList.add(activityInstance.getActivityId());
            }
            
            // 獲取bpmnModel
            BpmnModel bpmnModel = repositoryService.getBpmnModel(historicProcessInstance.getProcessDefinitionId());
            // 獲取流程已發生流轉的線ID集合
            List<String> flowIds = this.getExecutedFlows(bpmnModel, historicActivityInstanceList);
            
            // 使用默認配置獲得流程圖表生成器，並生成追蹤圖片字符流
            ProcessDiagramGenerator processDiagramGenerator = processEngine.getProcessEngineConfiguration().getProcessDiagramGenerator();
            InputStream imageStream = processDiagramGenerator.generateDiagram(bpmnModel, "png", executedActivityIdList, flowIds, "宋體", "微軟雅黑", "黑體", null, 2.0);
            return imageStream;
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }

　　以下方法獲取所有已流轉的線，由於並行網關與包含網關可能存在多個流轉，所以要找到全部符合要求的Flow，其它類型的節點只查找歷史活動實例中的第一個節點：

    private List<String> getExecutedFlows(BpmnModel bpmnModel, List<HistoricActivityInstance> historicActivityInstances) {
        // 流轉線ID集合
        List<String> flowIdList = new ArrayList<String>();
        // 全部活動實例
        List<FlowNode> historicFlowNodeList = new LinkedList<FlowNode>();
        // 已完成的歷史活動節點
        List<HistoricActivityInstance> finishedActivityInstanceList = new LinkedList<HistoricActivityInstance>();
        for (HistoricActivityInstance historicActivityInstance : historicActivityInstances) {
            historicFlowNodeList.add((FlowNode) bpmnModel.getMainProcess().getFlowElement(historicActivityInstance.getActivityId(), true));
            if (historicActivityInstance.getEndTime() != null) {
                finishedActivityInstanceList.add(historicActivityInstance);
            }
        }
        
        // 遍歷已完成的活動實例，從每個實例的outgoingFlows中找到已執行的
        FlowNode currentFlowNode = null;
        for (HistoricActivityInstance currentActivityInstance : finishedActivityInstanceList) {
            // 獲得當前活動對應的節點信息及outgoingFlows信息
            currentFlowNode = (FlowNode) bpmnModel.getMainProcess().getFlowElement(currentActivityInstance.getActivityId(), true);
            List<SequenceFlow> sequenceFlowList = currentFlowNode.getOutgoingFlows();
            
            /**
             * 遍歷outgoingFlows並找到已已流轉的
             * 滿足如下條件認為已已流轉：
             * 1.當前節點是並行網關或包含網關，則通過outgoingFlows能夠在歷史活動中找到的全部節點均為已流轉
             * 2.當前節點是以上兩種類型之外的，通過outgoingFlows查找到的時間最近的流轉節點視為有效流轉
             */
            FlowNode targetFlowNode = null;
            if (BpmsActivityTypeEnum.PARALLEL_GATEWAY.getType().equals(currentActivityInstance.getActivityType())
                    || BpmsActivityTypeEnum.INCLUSIVE_GATEWAY.getType().equals(currentActivityInstance.getActivityType())) {
                // 遍歷歷史活動節點，找到匹配Flow目標節點的
                for (SequenceFlow sequenceFlow : sequenceFlowList) {
                    targetFlowNode = (FlowNode) bpmnModel.getMainProcess().getFlowElement(sequenceFlow.getTargetRef(), true);
                    if (historicFlowNodeList.contains(targetFlowNode)) {
                        flowIdList.add(sequenceFlow.getId());
                    }
                }
            } else {
                List<Map<String, String>> tempMapList = new LinkedList<Map<String,String>>();
                // 遍歷歷史活動節點，找到匹配Flow目標節點的
                for (SequenceFlow sequenceFlow : sequenceFlowList) {
                    for (HistoricActivityInstance historicActivityInstance : historicActivityInstances) {
                        if (historicActivityInstance.getActivityId().equals(sequenceFlow.getTargetRef())) {
                            tempMapList.add(UtilMisc.toMap("flowId", sequenceFlow.getId(), "activityStartTime", String.valueOf(historicActivityInstance.getStartTime().getTime())));
                        }
                    }
                }
                
                // 遍歷匹配的集合，取得開始時間最早的一個
                long earliestStamp = 0L;
                String flowId = null;
                for (Map<String, String> map : tempMapList) {
                    long activityStartTime = Long.valueOf(map.get("activityStartTime"));
                    if (earliestStamp == 0 || earliestStamp >= activityStartTime) {
                        earliestStamp = activityStartTime;
                        flowId = map.get("flowId");
                    }
                }
                flowIdList.add(flowId);
            }
        }
        return flowIdList;
    }

　　枚舉說明：

public enum BpmsActivityTypeEnum {
    
    START_EVENT("startEvent", "開始事件"),
    END_EVENT("endEvent", "結束事件"),
    USER_TASK("userTask", "用戶任務"),
    EXCLUSIVE_GATEWAY("exclusiveGateway", "排他網關"),
    PARALLEL_GATEWAY("parallelGateway", "並行網關"),
    INCLUSIVE_GATEWAY("inclusiveGateway", "包含網關");
    
    private String type;
    private String name;
    
    private BpmsActivityTypeEnum(String type, String name) {
        this.type = type;
        this.name = name;
    }
    
    public String getType() {
        return type;
    }
    public void setType(String type) {
        this.type = type;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
}

　　工具方法：

public class UtilMisc {
    public static <V, V1 extends V, V2 extends V> Map<String, V> toMap(String name1, V1 value1, String name2, V2 value2) {
        return populateMap(new HashMap<String, V>(), name1, value1, name2, value2);
    }
    @SuppressWarnings("unchecked")
    private static <K, V> Map<String, V> populateMap(Map<String, V> map, Object... data) {
        for (int i = 0; i < data.length;) {
            map.put((String) data[i++], (V) data[i++]);
        }
        return map;
    }
}

 

　　看一個簡單的生成效果：

　　在按照流程節點類型做區分處理上，考慮的不是特別周全，希望有用到的朋友遇到了問題能夠與我分享，一起探討更好的解決方式~