Prevent adding/setting parent component as child (#12720).

Change-Id: I9b7b43f176e88d9edca591001297b94475a31854

3 files changed, 30 insertions, 9 deletions

diff --git a/server/src/com/vaadin/ui/AbstractComponent.java b/server/src/com/vaadin/ui/AbstractComponent.java
index d980c27916..b6289e0b7d 100644
--- a/server/src/com/vaadin/ui/AbstractComponent.java
+++ b/server/src/com/vaadin/ui/AbstractComponent.java
@@ -991,4 +991,24 @@ public abstract class AbstractComponent extends AbstractClientConnector
             actionManager.removeAction(shortcut);
         }
     }
+
+    /**
+     * Determine whether a <code>content</code> component is equal to, or the
+     * ancestor of this component.
+     * 
+     * @param content
+     *            the potential ancestor element
+     * @return <code>true</code> if the relationship holds
+     */
+    protected boolean isOrHasAncestor(Component content) {
+        if (content instanceof HasComponents) {
+            for (Component parent = this; parent != null; parent = parent
+                    .getParent()) {
+                if (parent == content) {
+                    return true;
+                }
+            }
+        }
+        return false;
+    }
 }
diff --git a/server/src/com/vaadin/ui/AbstractComponentContainer.java b/server/src/com/vaadin/ui/AbstractComponentContainer.java
index 0aa185d557..b1e69ba76b 100644
--- a/server/src/com/vaadin/ui/AbstractComponentContainer.java
+++ b/server/src/com/vaadin/ui/AbstractComponentContainer.java
@@ -196,15 +196,10 @@ public abstract class AbstractComponentContainer extends AbstractComponent
      */
     @Override
     public void addComponent(Component c) {
-        if (c instanceof ComponentContainer) {
-            // Make sure we're not adding the component inside it's own content
-            for (Component parent = this; parent != null; parent = parent
-                    .getParent()) {
-                if (parent == c) {
-                    throw new IllegalArgumentException(
-                            "Component cannot be added inside it's own content");
-                }
-            }
+        // Make sure we're not adding the component inside it's own content
+        if (isOrHasAncestor(c)) {
+            throw new IllegalArgumentException(
+                    "Component cannot be added inside it's own content");
         }
 
         if (c.getParent() != null) {
diff --git a/server/src/com/vaadin/ui/AbstractSingleComponentContainer.java b/server/src/com/vaadin/ui/AbstractSingleComponentContainer.java
index de1bb29846..ba108fc302 100644
--- a/server/src/com/vaadin/ui/AbstractSingleComponentContainer.java
+++ b/server/src/com/vaadin/ui/AbstractSingleComponentContainer.java
@@ -123,6 +123,12 @@ public abstract class AbstractSingleComponentContainer extends
      */
     @Override
     public void setContent(Component content) {
+        // Make sure we're not adding the component inside it's own content
+        if (isOrHasAncestor(content)) {
+            throw new IllegalArgumentException(
+                    "Component cannot be added inside it's own content");
+        }
+
         Component oldContent = getContent();
         if (oldContent == content) {
             // do not set the same content twice