Minor modification, added Null Analysis related annotations

TULIP/src/lu/list/itis/dkd/tui/space/SpatialMatrix.java

@@ -17,6 +17,7 @@
 package lu.list.itis.dkd.tui.space;
 
 import lu.list.itis.dkd.dbc.annotation.NonNullByDefault;
+import lu.list.itis.dkd.dbc.annotation.Nullable;
 import lu.list.itis.dkd.tui.TangibleObjectManager;
 import lu.list.itis.dkd.tui.adapter.TangibleObject;
 import lu.list.itis.dkd.tui.widget.BaseWidget;
@@ -316,8 +317,11 @@ public class SpatialMatrix {
      * @return The object with the smallest x-axis coordinate. Returns the first if more than one
      *         are tied.
      */
-    public TangibleObject getLeftMostObject() {
-        return horizontal.get(0);
+    public @Nullable TangibleObject getLeftMostObject() {
+        if (horizontal.size() > 0) {
+            return horizontal.get(0);
+        }
+        return null;
     }
 
     /**
@@ -327,8 +331,11 @@ public class SpatialMatrix {
      * @return The object with the largest x-axis coordinate. Returns the last if more than one are
      *         tied.
      */
-    public TangibleObject getRightMostObject() {
-        return horizontal.get(horizontal.size() - 1);
+    public @Nullable TangibleObject getRightMostObject() {
+        if (horizontal.size() > 0) {
+            return horizontal.get(horizontal.size() - 1);
+        }
+        return null;
     }
 
     /**
@@ -339,7 +346,10 @@ public class SpatialMatrix {
      *         are tied.
      */
     public TangibleObject getTopObject() {
-        return vertical.get(0);
+        if (vertical.size() > 0) {
+            return vertical.get(0);
+        }
+        return null;
     }
 
     /**
@@ -350,7 +360,10 @@ public class SpatialMatrix {
      *         tied.
      */
     public TangibleObject getBottomObject() {
-        return vertical.get(vertical.size() - 1);
+        if (vertical.size() > 0) {
+            return vertical.get(vertical.size() - 1);
+        }
+        return null;
     }
 
     /**

TULIP/src/lu/list/itis/dkd/tui/space/SpatialPositioningManager.java

@@ -16,6 +16,8 @@
  */
 package lu.list.itis.dkd.tui.space;
 
+import lu.list.itis.dkd.dbc.annotation.NonNullByDefault;
+import lu.list.itis.dkd.dbc.annotation.Nullable;
 import lu.list.itis.dkd.tui.TangibleObjectManager;
 import lu.list.itis.dkd.tui.adapter.TangibleObject;
 import lu.list.itis.dkd.tui.event.SpatialEvent;
@@ -54,6 +56,7 @@ import java.util.logging.Logger;
  * @since 2.1
  * @version 2.1.3
  */
+@NonNullByDefault
 public class SpatialPositioningManager implements SpatialEventListener {
 
     private static final Logger logger = Logger.getLogger(SpatialPositioningManager.class.getSimpleName());
@@ -66,6 +69,7 @@ public class SpatialPositioningManager implements SpatialEventListener {
      * Enumeration showing all alignment types this class supports.
      * 
      * @author Eric Tobias [eric.tobias@list.lu]
+     * @author Valérie Maquil [valerie.maquil@list.lu]
      * @since 2.1
      * @version 2.1.3
      */
@@ -172,7 +176,7 @@ public class SpatialPositioningManager implements SpatialEventListener {
      * @return The widget with the smallest x-axis coordinate. Returns the first if more than one
      *         are tied. Will return <code>null</code> if no object is present.
      */
-    public BaseWidget getLeftMostWidget() {
+    public @Nullable BaseWidget getLeftMostWidget() {
         if (getLeftMostObject() == null) {
             return null;
         }
@@ -185,7 +189,7 @@ public class SpatialPositioningManager implements SpatialEventListener {
      * 
      * @return The object with the smallest x coordinate.
      */
-    public TangibleObject getLeftMostObject() {
+    public @Nullable TangibleObject getLeftMostObject() {
         return spatialMatrix.getLeftMostObject();
     }
 
@@ -197,9 +201,10 @@ public class SpatialPositioningManager implements SpatialEventListener {
      * @return The widget with the largest x-axis coordinate. Returns the last if more than one are
      *         tied. Will return <code>null</code> if no object is present.
      */
-    public BaseWidget getRightMostWidget() {
-        if (getRightMostObject() == null)
+    public @Nullable BaseWidget getRightMostWidget() {
+        if (null == getRightMostObject()) {
             return null;
+        }
 
         return TangibleObjectManager.getWidget(getRightMostObject().getObjectId());
     }
@@ -209,7 +214,7 @@ public class SpatialPositioningManager implements SpatialEventListener {
      * 
      * @return The object with the largest x coordinate.
      */
-    public TangibleObject getRightMostObject() {
+    public @Nullable TangibleObject getRightMostObject() {
         return spatialMatrix.getRightMostObject();
     }
 
@@ -220,8 +225,8 @@ public class SpatialPositioningManager implements SpatialEventListener {
      * @return The widget with the smallest y-axis coordinate. Returns the first if more than one
      *         are tied. Will return <code>null</code> if no object is present.
      */
-    public BaseWidget getTopWidget() {
-        if (getTopObject() == null) {
+    public @Nullable BaseWidget getTopWidget() {
+        if (null == getTopObject()) {
             return null;
         }
 
@@ -233,7 +238,7 @@ public class SpatialPositioningManager implements SpatialEventListener {
      * 
      * @return The object with the smallest y coordinate.
      */
-    public TangibleObject getTopObject() {
+    public @Nullable TangibleObject getTopObject() {
         return spatialMatrix.getTopObject();
     }
 
@@ -244,7 +249,7 @@ public class SpatialPositioningManager implements SpatialEventListener {
      * @return The widget with the largest y-axis coordinate. Returns the last if more than one are
      *         tied. Will return <code>null</code> if no object is present.
      */
-    public BaseWidget getBottomWidget() {
+    public @Nullable BaseWidget getBottomWidget() {
         if (getBottomObject() == null) {
             return null;
         }
@@ -257,7 +262,7 @@ public class SpatialPositioningManager implements SpatialEventListener {
      * 
      * @return The object with the largest y coordinate.
      */
-    public TangibleObject getBottomObject() {
+    public @Nullable TangibleObject getBottomObject() {
         return spatialMatrix.getBottomObject();
     }
 
@@ -284,7 +289,6 @@ public class SpatialPositioningManager implements SpatialEventListener {
 
     public List<TangibleObject> getObjectToLeftOf(BaseWidget widget) {
         return spatialMatrix.leftOf(TangibleObjectManager.getIdentifier(widget));
-
     }
 
     /**