修改

src/main/java/edu/nju/dao/TaskDao.java

@@ -31,15 +31,17 @@ public class TaskDao {
         query.addCriteria(Criteria.where("_id").is(id));
         List<Task> tasks = mongoOperations.find(query, Task.class);
         if(tasks.size() == 0) {
+            System.out.println("tasks.size() == 0");
             return getAndSaveTaskInfo(id);
         }
         else { return tasks.get(0); }
     }
 
     private Task getAndSaveTaskInfo(String id){
-        System.out.println("调用主站（信创）获取考试信息");
+        System.out.println("调用主站（信创）获取考试信息-1 ");
         String result = HTTP.sendGet(mainSiteUrl + "/api/exam/" + id + "/info", "");
         if (!"".equals(result)) {
+            System.out.println("result1 " + result);
             JSONObject json = new JSONObject(result);
             long beginTime = json.getLong("beginTime");
             long endTime = json.getLong("endTime");

src/main/java/edu/nju/service/AnalyzeService.java

@@ -841,9 +841,12 @@ public class AnalyzeService {
 		String taskName="";
 		double writeMins=0.0;
 		if(task!=null) {
+			System.out.println("task!=null " + task!=null);
 			startTime = task.getStart_time();
 			endTime = task.getEnd_time();
 			writeMins = task.getTotal_mins();
+		}else{
+			System.out.println("task!=null " + task!=null);
 		}
 		if(exam!=null){
 			taskName = exam.getName();

src/main/java/edu/nju/service/ExtraService.java

@@ -187,9 +187,10 @@ public class ExtraService {
 	}
 
 	private Task getAndSaveTaskInfo(String id){
+		System.out.println("调用主站（信创）获取考试信息-2 ");
 		String result = HTTP.sendGet(mainSiteUrl + "/api/exam/" + id + "/info", "");
-		System.out.println("result " + result);
-		if (!result.equals("")) {
+		if (!"".equals(result)) {
+			System.out.println("result2 " + result);
 			JSONObject json = new JSONObject(result);
 			long beginTime = json.getLong("beginTime");
 			long endTime = json.getLong("endTime");