Ensure setting value on detached column group throws exception #3153

Change-Id: I4cef3424dfe846ab814fcf70c5cda4a305cbdf1c

3 files changed, 52 insertions, 3 deletions

diff --git a/server/src/com/vaadin/ui/components/grid/ColumnGroup.java b/server/src/com/vaadin/ui/components/grid/ColumnGroup.java
index 0ab1f61a46..6b14ef81d4 100644
--- a/server/src/com/vaadin/ui/components/grid/ColumnGroup.java
+++ b/server/src/com/vaadin/ui/components/grid/ColumnGroup.java
@@ -43,6 +43,11 @@ public class ColumnGroup implements Serializable {
     private final Grid grid;
 
     /**
+     * The column group row the column group is attached to
+     */
+    private final ColumnGroupRow row;
+
+    /**
      * The common state between the server and the client
      */
     private final ColumnGroupState state;
@@ -61,13 +66,15 @@ public class ColumnGroup implements Serializable {
      *            the sub groups who should be included in this group
      * 
      */
-    ColumnGroup(Grid grid, ColumnGroupState state, List<Object> propertyIds) {
+    ColumnGroup(Grid grid, ColumnGroupRow row, ColumnGroupState state,
+            List<Object> propertyIds) {
         if (propertyIds == null) {
             throw new IllegalArgumentException(
                     "propertyIds cannot be null. Use empty list instead.");
         }
 
         this.state = state;
+        this.row = row;
         columns = Collections.unmodifiableList(new ArrayList<Object>(
                 propertyIds));
         this.grid = grid;
@@ -80,6 +87,7 @@ public class ColumnGroup implements Serializable {
      *            the text displayed in the header of the column
      */
     public void setHeaderCaption(String header) {
+        checkGroupIsAttached();
         state.header = header;
         grid.markAsDirty();
     }
@@ -90,6 +98,7 @@ public class ColumnGroup implements Serializable {
      * @return the text displayed in the header of the column
      */
     public String getHeaderCaption() {
+        checkGroupIsAttached();
         return state.header;
     }
 
@@ -100,6 +109,7 @@ public class ColumnGroup implements Serializable {
      *            the text displayed in the footer of the column
      */
     public void setFooterCaption(String footer) {
+        checkGroupIsAttached();
         state.footer = footer;
         grid.markAsDirty();
     }
@@ -110,6 +120,7 @@ public class ColumnGroup implements Serializable {
      * @return the text displayed in the footer of the column
      */
     public String getFooterCaption() {
+        checkGroupIsAttached();
         return state.footer;
     }
 
@@ -138,4 +149,17 @@ public class ColumnGroup implements Serializable {
         return columns;
     }
 
+    /**
+     * Checks if column group is attached to a row and throws an
+     * {@link IllegalStateException} if it is not.
+     * 
+     * @throws IllegalStateException
+     *             if the column is no longer attached to any grid
+     */
+    protected void checkGroupIsAttached() throws IllegalStateException {
+        if (!row.getState().groups.contains(state)) {
+            throw new IllegalStateException(
+                    "Column Group has been removed from the row.");
+        }
+    }
 }
diff --git a/server/src/com/vaadin/ui/components/grid/ColumnGroupRow.java b/server/src/com/vaadin/ui/components/grid/ColumnGroupRow.java
index 326d2826f5..e82e24abec 100644
--- a/server/src/com/vaadin/ui/components/grid/ColumnGroupRow.java
+++ b/server/src/com/vaadin/ui/components/grid/ColumnGroupRow.java
@@ -111,7 +111,7 @@ public class ColumnGroupRow implements Serializable {
         }
         this.state.groups.add(state);
 
-        ColumnGroup group = new ColumnGroup(grid, state,
+        ColumnGroup group = new ColumnGroup(grid, this, state,
                 Arrays.asList(propertyIds));
         groups.add(group);
 
@@ -160,7 +160,7 @@ public class ColumnGroupRow implements Serializable {
         }
 
         ColumnGroupState state = new ColumnGroupState();
-        ColumnGroup group = new ColumnGroup(grid, state, propertyIds);
+        ColumnGroup group = new ColumnGroup(grid, this, state, propertyIds);
         this.groups.add(group);
 
         // Update state
diff --git a/server/tests/src/com/vaadin/tests/server/component/grid/GridColumnGroups.java b/server/tests/src/com/vaadin/tests/server/component/grid/GridColumnGroups.java
index cf1ee14437..11dc48f7d5 100644
--- a/server/tests/src/com/vaadin/tests/server/component/grid/GridColumnGroups.java
+++ b/server/tests/src/com/vaadin/tests/server/component/grid/GridColumnGroups.java
@@ -19,6 +19,7 @@ import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
 
 import java.lang.reflect.Field;
 import java.lang.reflect.Method;
@@ -208,4 +209,28 @@ public class GridColumnGroups {
         group.setFooterCaption(null);
         assertNull(group.getFooterCaption());
     }
+
+    @Test
+    public void testColumnGroupDetachment() throws Exception {
+
+        ColumnGroupRow row = grid.addColumnGroupRow();
+        ColumnGroup group = row.addGroup("column1", "column2");
+
+        // Remove group
+        row.removeGroup(group);
+
+        try {
+            group.setHeaderCaption("Header");
+            fail("Should throw exception for setting header caption on detached group");
+        } catch (IllegalStateException ise) {
+
+        }
+
+        try {
+            group.setFooterCaption("Footer");
+            fail("Should throw exception for setting footer caption on detached group");
+        } catch (IllegalStateException ise) {
+
+        }
+    }
 }