Improved completion processor

[phpeclipse.git] / net.sourceforge.phpeclipse / src / net / sourceforge / phpdt / internal / ui / viewsupport / ImageDescriptorRegistry.java

diff --git a/net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/ui/viewsupport/ImageDescriptorRegistry.java b/net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/ui/viewsupport/ImageDescriptorRegistry.java
new file mode 100644 (file)
index 0000000..ae34a4c
--- /dev/null
+++ b/net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/ui/viewsupport/ImageDescriptorRegistry.java
@@ -0,0 +1,86 @@
+/*
+ * (c) Copyright IBM Corp. 2000, 2001.
+ * All Rights Reserved.
+ */
+package net.sourceforge.phpdt.internal.ui.viewsupport;
+
+import java.util.HashMap;
+import java.util.Iterator;
+
+import org.eclipse.swt.graphics.Image;
+import org.eclipse.swt.widgets.Display;
+
+import net.sourceforge.phpdt.internal.ui.util.SWTUtil;
+import org.eclipse.jface.resource.ImageDescriptor;
+import org.eclipse.jface.util.Assert;
+
+/**
+ * A registry that maps <code>ImageDescriptors</code> to <code>Image</code>.
+ */
+public class ImageDescriptorRegistry {
+
+       private HashMap fRegistry= new HashMap(10);
+       private Display fDisplay;
+       
+       /**
+        * Creates a new image descriptor registry for the current or default display,
+        * respectively.
+        */
+       public ImageDescriptorRegistry() {
+               this(SWTUtil.getStandardDisplay());
+       }
+       
+       /**
+        * Creates a new image descriptor registry for the given display. All images
+        * managed by this registry will be disposed when the display gets disposed.
+        * 
+        * @param diaplay the display the images managed by this registry are allocated for 
+        */
+       public ImageDescriptorRegistry(Display display) {
+               fDisplay= display;
+               Assert.isNotNull(fDisplay);
+               hookDisplay();
+       }
+       
+       /**
+        * Returns the image assiciated with the given image descriptor.
+        * 
+        * @param descriptor the image descriptor for which the registry manages an image
+        * @return the image associated with the image descriptor or <code>null</code>
+        *  if the image descriptor can't create the requested image.
+        */
+       public Image get(ImageDescriptor descriptor) {
+               if (descriptor == null)
+                       descriptor= ImageDescriptor.getMissingImageDescriptor();
+                       
+               Image result= (Image)fRegistry.get(descriptor);
+               if (result != null)
+                       return result;
+       
+               Assert.isTrue(fDisplay == SWTUtil.getStandardDisplay(), "Allocating image for wrong display."); //$NON-NLS-1$
+               result= descriptor.createImage();
+               if (result != null)
+                       fRegistry.put(descriptor, result);
+               return result;
+       }
+
+       /**
+        * Disposes all images managed by this registry.
+        */     
+       public void dispose() {
+               for (Iterator iter= fRegistry.values().iterator(); iter.hasNext(); ) {
+                       Image image= (Image)iter.next();
+                       image.dispose();
+               }
+               fRegistry.clear();
+       }
+       
+       private void hookDisplay() {
+               fDisplay.disposeExec(new Runnable() {
+                       public void run() {
+                               dispose();
+                       }       
+               });
+       }
+}
+