vtk/src/vtk/vtkJavaGarbageCollector.java

   1 package vtk;
   2
   3 import java.util.concurrent.Executors;
   4 import java.util.concurrent.ScheduledExecutorService;
   5 import java.util.concurrent.TimeUnit;
   6
   7 import javax.swing.SwingUtilities;
   8
   9 /**
  10  * This class helps to provide a solution in concurrent garbage collection issue
  11  * with VTK. This class allow automatic garbage collection done in a specific
  12  * thread such as the EDT.
  13  *
  14  * @author sebastien jourdain - sebastien.jourdain@kitware.com
  15  */
  16 public class vtkJavaGarbageCollector {
  17
  18     private ScheduledExecutorService executor;
  19     private Runnable deleteRunnable;
  20     private Runnable deferredEdtRunnable;
  21     private long periodTime;
  22     private TimeUnit timeUnit;
  23     private boolean autoCollectionRunning;
  24     private boolean debug;
  25
  26     /**
  27      * Build a garbage collector which is configured to garbage collect every
  28      * seconds but has not been started yet. The user has to call
  29      * SetAutoGarbageCollection(true) to make it start.
  30      */
  31     public vtkJavaGarbageCollector() {
  32         // Default settings
  33         debug = false;
  34         periodTime = 1;
  35         timeUnit = TimeUnit.SECONDS;
  36         autoCollectionRunning = false;
  37         //
  38         executor = Executors.newSingleThreadScheduledExecutor();
  39         deleteRunnable = new Runnable() {
  40
  41             public void run() {
  42                 // Do the delete here
  43                 vtkReferenceInformation info = vtkObject.JAVA_OBJECT_MANAGER.gc(debug);
  44                 if (debug) {
  45                     System.out.println(info);
  46                     System.out.println(info.listKeptReferenceToString());
  47                     System.out.println(info.listRemovedReferenceToString());
  48                 }
  49             }
  50         };
  51         deferredEdtRunnable = new Runnable() {
  52
  53             public void run() {
  54                 SwingUtilities.invokeLater(deleteRunnable);
  55             }
  56         };
  57     }
  58
  59     /**
  60      * Set the schedule time that should be used to send a garbage collection
  61      * request to the EDT.
  62      *
  63      * @param period
  64      * @param timeUnit
  65      */
  66     public void SetScheduleTime(long period, TimeUnit timeUnit) {
  67         this.periodTime = period;
  68         this.timeUnit = timeUnit;
  69         SetAutoGarbageCollection(autoCollectionRunning);
  70     }
  71
  72     /**
  73      * Whether to print out when garbage collection is run.
  74      *
  75      * @param debug
  76      */
  77     public void SetDebug(boolean debug) {
  78         this.debug = debug;
  79     }
  80
  81     /**
  82      * Start or stop the automatic garbage collection in the EDT.
  83      *
  84      * @param doGarbageCollectionInEDT
  85      */
  86     public void SetAutoGarbageCollection(boolean doGarbageCollectionInEDT) {
  87         autoCollectionRunning = doGarbageCollectionInEDT;
  88         executor.shutdown();
  89         if (doGarbageCollectionInEDT) {
  90             executor = Executors.newSingleThreadScheduledExecutor();
  91             executor.scheduleAtFixedRate(deferredEdtRunnable, periodTime, periodTime, timeUnit);
  92         }
  93     }
  94
  95     /**
  96      * Shortcut for SetAutoGarbageCollection(true)
  97      * @see SetAutoGarbageCollection
  98      */
  99     public void Start() {
 100         this.SetAutoGarbageCollection(true);
 101     }
 102
 103     /**
 104      * Shortcut for SetAutoGarbageCollection(false)
 105      * @see SetAutoGarbageCollection
 106      */
 107     public void Stop() {
 108         this.SetAutoGarbageCollection(false);
 109     }
 110
 111     /**
 112      * @return the runnable that do the garbage collection. This could be used
 113      *         if you want to execute the garbage collection in another thread
 114      *         than the EDT.
 115      */
 116     public Runnable GetDeleteRunnable() {
 117         return deleteRunnable;
 118     }
 119 }