Changeset 17526 for gli/trunk/src/org/greenstone/gatherer/download/DownloadScrollPane.java

Timestamp:

2008-10-13T21:44:43+13:00 (16 years ago)

Author:

ak19

Message:

Dr Bainbridge adjusted code to replace the variable called busy which was used in a processor-intensive loop and causing problems when terminating wget from the Download panel when more than once download instance was running. The solution was to use Thread's wait and notify (see also DownloadJob.java).

File:

• gli/trunk/src/org/greenstone/gatherer/download/DownloadScrollPane.java (modified) (6 diffs)

gli/trunk/src/org/greenstone/gatherer/download/DownloadScrollPane.java

@@ -52 +52 @@
     extends Thread {
     
-    /** <i>true</i> if there is a task currently being carried out, <i>false</i> otherwise. */
-    private boolean busy = false;
     /** <i>true</i> if verbose debug messages should be displayed, <i>false</i> otherwise. */
     private boolean debug = false;
@@ -69 +67 @@
     private Vector job_queue;
     static final private boolean simple = true;
-    
+
+        
     public DownloadScrollPane() {
     job = null;
@@ -81 +80 @@
     public void deleteDownloadJob(DownloadJob delete_me) {
     if (delete_me == job) {
-        while(busy) {
-        }
+        try {
+        // Wait for the job to finish cleaning up, before we can continue cleaning up here.
+        // But sometimes the job has completed (terminated naturally) and in that case there's
+        // nothing to wait for.
+        synchronized(delete_me) {
+            if (!delete_me.hasSignalledStop()) { // don't wait if DownloadJob.COMPLETED 
+            delete_me.wait();
+            }
+        }
+        } catch (Exception e) {
+        e.printStackTrace();
+        }
+        
         job = null;
-    }
+        
+    }
+    // Get rid of this download's dedicated pane
+    finishedDownloadJob(delete_me);
+    }
+
+    /** To be called when a download job has terminated naturally or was prematurely stopped
+     *  via the close button. Gets rid of this download's pane with buttons and progress bar. */
+    protected void finishedDownloadJob(DownloadJob delete_me) {
     if (delete_me.hasSignalledStop()) {
         list_pane.remove(delete_me.getProgressBar());
@@ -131 +149 @@
 
     DebugStream.println("About to create a new job");
-
-
+    
         DownloadJob new_job = new DownloadJob(download, Configuration.proxy_pass, Configuration.proxy_user, this, mode, proxy_url);
     // Tell it to run as soon as possible
-
-      
 
     new_job.setState(DownloadJob.RUNNING);
@@ -165 +180 @@
     //list_pane.setAlignmentX(Component.LEFT_ALIGNMENT);
     list_pane.updateUI();
-    new_job = null;
+    new_job = null;         //job = (DownloadJob) job_queue.get(index);
+
     synchronized(this) {
         notify(); // Just incase its sleeping.
@@ -189 +205 @@
     while(true) {
         if(job_queue.size() > 0) {
-        int index = 0;
-        while(job_queue.size() > 0 && index < job_queue.size()) {
-            job = (DownloadJob) job_queue.get(index);
+        while(!job_queue.isEmpty()) { 
+            job = (DownloadJob) job_queue.firstElement(); 
+            
             if(job.getState() == DownloadJob.RUNNING) {
-            DebugStream.println("DownloadJob " + job.toString() + " Begun.");
-            busy = true;
+            DownloadJob delete_me = job;
+            String jobDisplayString = job.toString();
+            DebugStream.println("DownloadJob " + jobDisplayString + " Begun.");
+            System.err.println("DownloadJob " + job.port + " " + job.toString() + " Begun.");
             job.callDownload();
-            busy = false;
-            DebugStream.println("DownloadJob " + job.toString() + " complete.");
+            finishedDownloadJob(delete_me); // Job is done, get rid of the separate display panel for this download
+            System.err.println("DownloadJob " + jobDisplayString + " complete.");
+            DebugStream.println("DownloadJob " + jobDisplayString + " complete."); // by this point job is null!
             job = null;
-            }
-            index++;
+            delete_me = null;
+            }
         }
         try {