next try to fix loading of network picture

git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@7061 6c8d7289-2bf4-0310-a012-ef5d649a1542

htroot/NetworkPicture.java

@@ -39,7 +39,7 @@ import de.anomic.yacy.graphics.NetworkGraph;
 /** draw a picture of the yacy network */
 public class NetworkPicture {
     
-    private static final Semaphore sync = new Semaphore(1);
+    private static final Semaphore sync = new Semaphore(1, true);
     private static EncodedImage buffer = null;
     private static long lastAccessSeconds = 0;
     
@@ -49,17 +49,19 @@ public class NetworkPicture {
         
         long timeSeconds = System.currentTimeMillis() / 1000;
         if (buffer != null && !authorized && timeSeconds - lastAccessSeconds < 2) {
-            //System.out.println("*** NetworkPicture: cache hit (1)");
+            Log.logInfo("NetworkPicture", "cache hit (1); authorized = " + (authorized ? "true" : "false") + ", timeSeconds - lastAccessSeconds = " + (timeSeconds - lastAccessSeconds));
             return buffer;
         }
+        
         if (buffer != null && sync.availablePermits() == 0) return buffer;
-        try {
-            sync.acquire();
+        sync.acquireUninterruptibly();
+        
         if (buffer != null && !authorized  && timeSeconds - lastAccessSeconds < 2)  {
-                //System.out.println("*** NetworkPicture: cache hit (2)");
+            Log.logInfo("NetworkPicture", "cache hit (2); authorized = " + (authorized ? "true" : "false") + ", timeSeconds - lastAccessSeconds = " + (timeSeconds - lastAccessSeconds));
             sync.release();
             return buffer;
         }
+        
         int width = 768;
         int height = 576;
         int passiveLimit = 720; // 12 hours
@@ -97,9 +99,6 @@ public class NetworkPicture {
         buffer = new EncodedImage(NetworkGraph.getNetworkPicture(sb.peers, 10000, width, height, passiveLimit, potentialLimit, maxCount, coronaangle, communicationTimeout, env.getConfig(SwitchboardConstants.NETWORK_NAME, "unspecified"), env.getConfig("network.unit.description", "unspecified"), bgcolor).getImage(), "png");
         lastAccessSeconds = System.currentTimeMillis() / 1000;
         
-        } catch (Exception e) {
-            Log.logException(e);
-        }
         sync.release();
         return buffer;
     }