MapViewport { public AffineTransform getScreenToWorld() { lock.readLock().lock(); try { return screenToWorld == null ? null : new AffineTransform(screenToWorld); } finally { lock.readLock().unlock(); } } MapViewport();  MapViewport(boolean matchAspectRatio);  MapViewport(ReferencedEnvelope bounds);  MapViewport(ReferencedEnvelope bounds, boolean matchAspectRatio);  MapViewport(MapViewport sourceViewport); boolean isEditable(); void setEditable(boolean editable); void setMatchingAspectRatio(boolean enabled); boolean isMatchingAspectRatio(); void addMapBoundsListener(MapBoundsListener listener); void removeMapBoundsListener(MapBoundsListener listener); boolean isEmpty(); ReferencedEnvelope getBounds(); void setBounds(ReferencedEnvelope requestedBounds); Rectangle getScreenArea(); void setScreenArea(Rectangle screenArea); CoordinateReferenceSystem getCoordinateReferenceSystem(); void setCoordinateReferenceSystem(CoordinateReferenceSystem crs); AffineTransform getScreenToWorld(); AffineTransform getWorldToScreen();  }
@Test public void boundsCtorSetNullScreenToWorld() { MapViewport vp = new MapViewport(WORLD_1_1); assertNull( vp.getScreenToWorld() ); }