1 files changed, 21 insertions, 0 deletions
diff --git a/docs/examples/observer/Subject.java b/docs/examples/observer/Subject.java
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+++ b/docs/examples/observer/Subject.java
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+/*
+Copyright (c) Xerox Corporation 1998-2002.  All rights reserved.
+
+Use and copying of this software and preparation of derivative works based
+upon this software are permitted.  Any distribution of this software or
+derivative works must comply with all applicable United States export control
+laws.
+
+This software is made available AS IS, and Xerox Corporation makes no warranty
+about the software, its performance or its conformity to any specification.
+*/
+
+package observer;
+import java.util.Vector;
+
+interface Subject {
+    void addObserver(Observer obs);
+    void removeObserver(Observer obs);
+    Vector getObservers();
+    Object getData();
+}