[492003] Fix potential usage of already disposed Font

Bug: 492003
Change-Id: Ic733712447a91bb662c13576d54a52863fc0d967
Signed-off-by: Pierre-Charles David <pierre-charles.david@obeo.fr>

1 files changed, 6 insertions, 2 deletions

diff --git a/plugins/org.eclipse.sirius.diagram.ui/src-diag/org/eclipse/sirius/diagram/ui/internal/edit/parts/SiriusEditPartFactory.java b/plugins/org.eclipse.sirius.diagram.ui/src-diag/org/eclipse/sirius/diagram/ui/internal/edit/parts/SiriusEditPartFactory.java
index 93cebe0228..6815e4b4f9 100644
--- a/plugins/org.eclipse.sirius.diagram.ui/src-diag/org/eclipse/sirius/diagram/ui/internal/edit/parts/SiriusEditPartFactory.java
+++ b/plugins/org.eclipse.sirius.diagram.ui/src-diag/org/eclipse/sirius/diagram/ui/internal/edit/parts/SiriusEditPartFactory.java
@@ -28,6 +28,7 @@ import org.eclipse.sirius.diagram.ui.graphical.edit.part.specific.BracketEdgeEdi
 import org.eclipse.sirius.diagram.ui.part.SiriusVisualIDRegistry;
 import org.eclipse.sirius.diagram.ui.tools.api.figure.SiriusWrapLabel;
 import org.eclipse.swt.SWT;
+import org.eclipse.swt.graphics.Font;
 import org.eclipse.swt.widgets.Text;
 
 /**
@@ -223,8 +224,11 @@ public class SiriusEditPartFactory implements EditPartFactory {
             if (getWrapLabel().isTextWrapped() && getWrapLabel().getText().length() > 0) {
                 rect.setSize(new Dimension(text.computeSize(rect.width, SWT.DEFAULT)));
             } else {
-                final int avr = FigureUtilities.getFontMetrics(text.getFont()).getAverageCharWidth();
-                rect.setSize(new Dimension(text.computeSize(SWT.DEFAULT, SWT.DEFAULT)).expand(avr * 2, 0));
+                Font font = text.getFont();
+                if (font != null && !font.isDisposed()) {
+                    final int avr = FigureUtilities.getFontMetrics(font).getAverageCharWidth();
+                    rect.setSize(new Dimension(text.computeSize(SWT.DEFAULT, SWT.DEFAULT)).expand(avr * 2, 0));
+                }
             }
             if (!rect.equals(new Rectangle(text.getBounds()))) {
                 text.setBounds(rect.x, rect.y, rect.width + 1, rect.height);