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diff --git a/libjava/java/lang/CharSequence.java b/libjava/java/lang/CharSequence.java
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+/* java.lang.CharSequence -- Anything that has an indexed sequence of chars
+   Copyright (C) 2001 Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+ 
+GNU Classpath is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+02111-1307 USA.
+
+As a special exception, if you link this library with other files to
+produce an executable, this library does not by itself cause the
+resulting executable to be covered by the GNU General Public License.
+This exception does not however invalidate any other reasons why the
+executable file might be covered by the GNU General Public License. */
+
+
+package java.lang;
+
+/**
+ * General functions on a sequence of chars. This interface is implemented
+ * by <code>String</code>, <code>StringBuffer</code> and
+ * <code>CharBuffer</code> to give a uniform way to get chars at a certain
+ * index, the number of characters in the sequence and a subrange of the
+ * chars. Indexes start at 0 and the last index is <code>length()-1</code>.
+ * <p>
+ * Even when classes implement this interface they are not always
+ * exchangeble because they might implement their compare, equals or hash
+ * function differently. This means that in general one should not use a
+ * <code>CharSequence</code> as keys in collections since two sequences
+ * with the same chars at the same indexes with the same length might not
+ * have the same hash code, be equal or be comparable since the are
+ * represented by different classes.
+ *
+ * @author Mark Wielaard (mark@klomp.org)
+ *
+ * @since 1.4
+ */
+
+public interface CharSequence {
+
+    /**
+     * Returns the character at the given index.
+     *
+     * @exception IndexOutOfBoundsException when <code>i &lt; 0</code> or
+     * <code>i &gt; length()-1</code>.
+     */
+    char charAt(int i);
+
+    /**
+     * Returns the length of the sequence.
+     */
+    int length();
+
+    /**
+     * Returns a new <code>CharSequence</char> of the indicated range.
+     *
+     * @exception IndexOutOfBoundsException when <code>begin &lt; 0</code>,
+     *         <code>end &lt; 0</code>, <code>end &gt; length()</code> or
+     *         <code>begin &gt; end</code>
+     */
+    CharSequence subSequence(int begin, int end);
+
+    /**
+     * Returns the complete <code>CharSequence</code> as a <code>String</code>.
+     * Classes that implement this interface should return a <code>String</code>
+     * which contains only the characters in the sequence in the correct order.
+     */
+    String toString();
+}