Modified Case class to be TSK error observer

Core/src/org/sleuthkit/autopsy/casemodule/Case.java

@@ -86,12 +86,12 @@ import org.sleuthkit.datamodel.TskException;
  * open at a time. Use getCurrentCase() to retrieve the object for the current
  * case.
  */
-public class Case {
+public class Case implements SleuthkitCase.ErrorObserver {
 
     private static final String autopsyVer = Version.getVersion(); // current version of autopsy. Change it when the version is changed
     private static final String EVENT_CHANNEL_NAME = "%s-Case-Events";
     private static String appName = null;
-    private IntervalErrorReportData tskErrorReporter = null;
+    volatile private IntervalErrorReportData tskErrorReporter = null;
     private static final int MIN_SECONDS_BETWEEN_ERROR_REPORTS = 60; // No less than 60 seconds between warnings for errors
     private static final int MAX_SANITIZED_NAME_LENGTH = 47;
 
@@ -372,6 +372,17 @@ public class Case {
         }
     }
     
+    @Override
+    public void receiveError(String context, String errorMessage) {
+        /* NOTE: We are accessing currentCase.tskErrorReporter from two different threads.
+         * This is ok as long as we only read the value of currentCase.tskErrorReporter
+         * because currentCase.tskErrorReporter is declared as volatile.
+         */
+        if (null != currentCase.tskErrorReporter) {
+            currentCase.tskErrorReporter.addProblems(context, errorMessage);
+        }
+    }
+
     AddImageProcess makeAddImageProcess(String timezone, boolean processUnallocSpace, boolean noFatOrphans) {
         return this.db.makeAddImageProcess(timezone, processUnallocSpace, noFatOrphans);
     }

Core/src/org/sleuthkit/autopsy/casemodule/IntervalErrorReportData.java

@@ -20,16 +20,15 @@ package org.sleuthkit.autopsy.casemodule;
 
 import org.openide.util.NbBundle;
 import org.sleuthkit.autopsy.coreutils.MessageNotifyUtil;
-import org.sleuthkit.datamodel.SleuthkitCase;
 
 /**
  * This class enables capturing errors and batching them for reporting on a
- * no-more-than-x number of seconds basis. When created, you specify what type
+ * no-more-than-x number of seconds basis. When created, you specify the minimum
- * of error it will be batching, and the minimum time between user
+ * time between user notifications. When the time between notifications has
- * notifications. When the time between notifications has expired, the next
+ * expired, the next error encountered will cause a report to be shown to the
- * error encountered will cause a report to be shown to the user.
+ * user.
  */
-class IntervalErrorReportData implements SleuthkitCase.ErrorObserver {
+class IntervalErrorReportData {
 
     private final Case currentCase;
     private long newProblems;
@@ -39,7 +38,8 @@ class IntervalErrorReportData implements SleuthkitCase.ErrorObserver {
     private final String message;
 
     /**
-     * Create a new IntervalErrorReprotData instance.
+     * Create a new IntervalErrorReprotData instance and subscribe for TSK error
+     * notifications for the current case.
      *
      * @param currentCase           Case for which TSK errors should be tracked
      *                              and displayed.
@@ -48,21 +48,21 @@ class IntervalErrorReportData implements SleuthkitCase.ErrorObserver {
      * @param message               The message that will be shown when warning
      *                              the user
      */
-    public IntervalErrorReportData(Case currentCase, int secondsBetweenReports, String message) {
+    IntervalErrorReportData(Case currentCase, int secondsBetweenReports, String message) {
         this.newProblems = 0;
         this.totalProblems = 0;
         this.lastReportedDate = 0; // arm the first warning by choosing zero
         this.milliSecondsBetweenReports = secondsBetweenReports * 1000;  // convert to milliseconds
         this.message = message;
         this.currentCase = currentCase;
-        this.currentCase.getSleuthkitCase().addErrorObserver(this); // it's ok to use "this" at the end of the constructor
+        this.currentCase.getSleuthkitCase().addErrorObserver(this.currentCase);
     }
     
     /**
-     * Shuts down this IntervalErrorReprotData instance.
+     * Un-subscribe from TSK error notifications for current case.
      */
-    public void shutdown() {
+    void shutdown() {
-        this.currentCase.getSleuthkitCase().removeErrorObserver(this);
+        this.currentCase.getSleuthkitCase().removeErrorObserver(this.currentCase);
     }
 
     /**
@@ -70,12 +70,11 @@ class IntervalErrorReportData implements SleuthkitCase.ErrorObserver {
      * (or if this is the first problem encountered), a warning will be shown to
      * the user.
      *
-     * @param newProblems  the newProblems to set
      * @param context      The context in which the error occurred.
      * @param errorMessage A description of the error that occurred.
      */
-    private void addProblems(long newProblems, String context, String errorMessage) {
+    void addProblems(String context, String errorMessage) {
-        this.newProblems += newProblems;
+        this.newProblems += 1;
         this.totalProblems += newProblems;
 
         long currentTimeStamp = System.currentTimeMillis();
@@ -90,9 +89,4 @@ class IntervalErrorReportData implements SleuthkitCase.ErrorObserver {
             this.newProblems = 0;
         }
     }
-
-    @Override
-    public void receiveError(String context, String errorMessage) {
-        addProblems(1, context, errorMessage);
-    }
 }