add synchronize statement for modifying eventlist and serializing eventlist. (microsoft#103)

andxu · web-flow · commit dd4ae89c249c · 2017-11-15T08:31:32.000+08:00
diff --git a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/UsageDataSession.java b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/UsageDataSession.java
@@ -137,7 +137,9 @@ public void submitUsageData() {
         props.put("commandCount", JsonUtils.toJson(commandCountMap));
         props.put("breakpointCount", JsonUtils.toJson(breakpointCountMap));
         if (jdiEventSequenceEnabled) {
-            props.put("jdiEventSequence", JsonUtils.toJson(eventList));
+            synchronized (eventList) {
+                props.put("jdiEventSequence", JsonUtils.toJson(eventList));
+            }
         }
         usageDataLogger.log(Level.INFO, "session usage data summary", props);
     }
@@ -152,7 +154,9 @@ public static void recordEvent(Event event) {
                 Map<String, String> eventEntry = new HashMap<>();
                 eventEntry.put("timestamp", String.valueOf(System.currentTimeMillis()));
                 eventEntry.put("event", event.toString());
-                currentSession.eventList.add(JsonUtils.toJson(eventEntry));
+                synchronized (currentSession.eventList) {
+                    currentSession.eventList.add(JsonUtils.toJson(eventEntry));
+                }
             }
         } catch (Exception e) {
             logger.log(Level.SEVERE, String.format("Exception on recording event: %s.", e.toString()), e);
