1 files changed, 108 insertions, 0 deletions
diff --git a/sca-java-1.x/tags/java-M1-final/java/sca/model/src/main/java/org/apache/tuscany/model/util/NotifyingList.java b/sca-java-1.x/tags/java-M1-final/java/sca/model/src/main/java/org/apache/tuscany/model/util/NotifyingList.java
new file mode 100644
index 0000000000..1f064e0977
--- /dev/null
+++ b/sca-java-1.x/tags/java-M1-final/java/sca/model/src/main/java/org/apache/tuscany/model/util/NotifyingList.java
@@ -0,0 +1,108 @@
+/**
+ *
+ *  Copyright 2005 The Apache Software Foundation or its licensors, as applicable.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+package org.apache.tuscany.model.util;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+
+/**
+ * A list that invokes added or removed methods when elements are added or removed.
+ *
+ */
+public abstract class NotifyingList<E> extends ArrayList<E> {
+    
+    private boolean frozen;
+    
+    public NotifyingList() {
+    }
+    
+    public void freeze() {
+        frozen=true;
+    }
+    
+    protected void checkNotFrozen() {
+        if (frozen)
+            throw new IllegalStateException("Attempt to modify a frozen list");
+    }
+    
+    public boolean add(E element) {
+        checkNotFrozen();
+        boolean result=super.add(element);
+        added(element);
+        return result;
+    }
+    
+    public void add(int index, E element) {
+        checkNotFrozen();
+        super.add(index, element);
+        added(element);
+    }
+    
+    public boolean addAll(Collection<? extends E> c) {
+        checkNotFrozen();
+        boolean result=super.addAll(c);
+        for (E element : c)
+            added(element);
+        return result;
+    }
+    
+    public boolean addAll(int index, Collection<? extends E> c) {
+        checkNotFrozen();
+        boolean result=super.addAll(index, c);
+        for (E element : c)
+            added(element);
+        return result;
+    }
+    
+    public void clear() {
+        checkNotFrozen();
+        List<E> l=new ArrayList<E>(this);
+        super.clear();
+        for (E element : l)
+            removed(element);
+    }
+    
+    public E remove(int index) {
+        checkNotFrozen();
+        E element=super.remove(index);
+        removed(element);
+        return element;
+    }
+    
+    @SuppressWarnings("unchecked")
+    public boolean remove(Object element) {
+        checkNotFrozen();
+        boolean result=super.remove(element);
+        removed((E)element);
+        return result;
+    }
+    
+    @SuppressWarnings("unchecked")
+    public boolean removeAll(Collection<?> c) {
+        checkNotFrozen();
+        boolean result=super.removeAll(c);
+        for (E element : (Collection<? extends E>)c)
+            removed(element);
+        return result;
+    }
+
+    protected abstract void added(E element);
+    
+    protected abstract void removed(E element);
+    
+}