Message bubble display access fix (#367)

* Fixed Problems with this method if setGraphics was never called and there was no run

Signed-off-by: Michael Sementsov <michael.sementsov@ibykus.de>

* safe-check for available ViewportPane (display)

Signed-off-by: Frank Gasdorf <fgdrf@users.sourceforge.net>

Co-authored-by: Michael Sementsov <michael.sementsov@ibykus.de>

plugins/org.locationtech.udig.tool.edit.tests/META-INF/MANIFEST.MF

@@ -14,6 +14,7 @@ Require-Bundle: org.eclipse.ui,
  org.locationtech.udig.ui,
  org.locationtech.udig.ui.tests,
  org.junit;bundle-version="[4.0.0,5.0.0)",
- org.locationtech.udig.project.ui.tests
+ org.locationtech.udig.project.ui.tests,
+ org.easymock;bundle-version="2.4.0"
 Bundle-ActivationPolicy: lazy
 Bundle-RequiredExecutionEnvironment: JavaSE-1.8

plugins/org.locationtech.udig.tool.edit.tests/src/org/locationtech/udig/tools/edit/animation/MessageBubbleTest.java

@@ -0,0 +1,64 @@
+package org.locationtech.udig.tools.edit.animation;
+
+import static org.junit.Assert.assertFalse;
+
+import org.easymock.EasyMock;
+import org.eclipse.core.runtime.NullProgressMonitor;
+import org.junit.Test;
+import org.locationtech.udig.project.ui.render.displayAdapter.ViewportPane;
+import org.locationtech.udig.ui.graphics.ViewportGraphics;
+
+public class MessageBubbleTest {
+
+    ViewportPane viewportPaneMock = EasyMock.createNiceMock(ViewportPane.class);
+
+    ViewportGraphics viewportGraphicsMock = EasyMock.createNiceMock(ViewportGraphics.class);
+
+    MessageBubble messageBubble = new MessageBubble(0, 0, "whatever", (short) 1);
+
+    @Test
+    public void withoutGraphicContextNoNPEonSetValid() {
+        messageBubble.setValid(false);
+        assertFalse(messageBubble.isValid());
+    }
+
+
+    @Test
+    public void withoutsetGraphicContextWithNonNullDisplayRegistersListeners() {
+        viewportPaneMock.addMouseListener(EasyMock.anyObject());
+        EasyMock.expectLastCall().once();
+        viewportPaneMock.addMouseWheelListener(EasyMock.anyObject());
+        EasyMock.expectLastCall().once();
+
+        EasyMock.replay(viewportGraphicsMock, viewportPaneMock);
+        messageBubble.setGraphics(viewportGraphicsMock, viewportPaneMock);
+        EasyMock.verify(viewportGraphicsMock, viewportPaneMock);
+    }
+
+    @Test
+    public void withoutGraphicContextListenersRemoveNeverCalled() {
+        viewportPaneMock.removeMouseListener(EasyMock.anyObject());
+        EasyMock.expectLastCall().once();
+        viewportPaneMock.removeMouseWheelListener(EasyMock.anyObject());
+        EasyMock.expectLastCall().once();
+
+        EasyMock.replay(viewportGraphicsMock, viewportPaneMock);
+
+        messageBubble.setGraphics(viewportGraphicsMock, viewportPaneMock);
+
+        messageBubble.setValid(false);
+        assertFalse(messageBubble.isValid());
+
+        EasyMock.verify(viewportGraphicsMock, viewportPaneMock);
+    }
+
+    @Test
+    public void runWithoutViewportPaneDoesNotDoAnything() throws Exception {
+        EasyMock.replay(viewportGraphicsMock);
+
+        messageBubble.setGraphics(viewportGraphicsMock, null);
+
+        messageBubble.run(new NullProgressMonitor());
+        EasyMock.verify(viewportGraphicsMock);
+    }
+}

plugins/org.locationtech.udig.tool.edit/src/org/locationtech/udig/tools/edit/animation/MessageBubble.java

@@ -82,14 +82,25 @@ public boolean hasNext() {
     public void nextFrame() {
     }
 
+    @Override
+    public void setGraphics(ViewportGraphics graphics, IMapDisplay mapDisplay) {
+        super.setGraphics(graphics, mapDisplay);
+
+        if (display != null) {
+            display.addMouseListener(mouseListener);
+            display.addMouseWheelListener(wheelListener);
+        }
+    }
+
     public void run( IProgressMonitor monitor ) throws Exception {
+        if (display == null) {
+            return;
+        }
+
         if (myFont != null){
             graphics.setFont(myFont);
         }
-
-        display.addMouseListener(mouseListener);
-        display.addMouseWheelListener(wheelListener);
-
+
         Rectangle2D messageBounds=new Rectangle(0,0);
 
         for( String part : message ) {
@@ -221,8 +232,10 @@ public void setTextColor( Color textColor ) {
     @Override
     public void setValid( boolean valid ) {
         super.setValid(valid);
-        display.removeMouseListener(mouseListener);
-        display.removeMouseWheelListener(wheelListener);
+        if (display != null) {
+            display.removeMouseListener(mouseListener);
+            display.removeMouseWheelListener(wheelListener);
+        }
     }
 
     private MapMouseListener mouseListener=new MapMouseListener(){