--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/java/lang/Appendable.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,121 @@
+/*
+ * Copyright 2003-2004 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code 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
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package java.lang;
+
+import java.io.IOException;
+
+/**
+ * An object to which <tt>char</tt> sequences and values can be appended.  The
+ * <tt>Appendable</tt> interface must be implemented by any class whose
+ * instances are intended to receive formatted output from a {@link
+ * java.util.Formatter}.
+ *
+ * <p> The characters to be appended should be valid Unicode characters as
+ * described in <a href="Character.html#unicode">Unicode Character
+ * Representation</a>.  Note that supplementary characters may be composed of
+ * multiple 16-bit <tt>char</tt> values.
+ *
+ * <p> Appendables are not necessarily safe for multithreaded access.  Thread
+ * safety is the responsibility of classes that extend and implement this
+ * interface.
+ *
+ * <p> Since this interface may be implemented by existing classes
+ * with different styles of error handling there is no guarantee that
+ * errors will be propagated to the invoker.
+ *
+ * @since 1.5
+ */
+public interface Appendable {
+
+    /**
+     * Appends the specified character sequence to this <tt>Appendable</tt>.
+     *
+     * <p> Depending on which class implements the character sequence
+     * <tt>csq</tt>, the entire sequence may not be appended.  For
+     * instance, if <tt>csq</tt> is a {@link java.nio.CharBuffer} then
+     * the subsequence to append is defined by the buffer's position and limit.
+     *
+     * @param  csq
+     *         The character sequence to append.  If <tt>csq</tt> is
+     *         <tt>null</tt>, then the four characters <tt>"null"</tt> are
+     *         appended to this Appendable.
+     *
+     * @return  A reference to this <tt>Appendable</tt>
+     *
+     * @throws  IOException
+     *          If an I/O error occurs
+     */
+    Appendable append(CharSequence csq) throws IOException;
+
+    /**
+     * Appends a subsequence of the specified character sequence to this
+     * <tt>Appendable</tt>.
+     *
+     * <p> An invocation of this method of the form <tt>out.append(csq, start,
+     * end)</tt> when <tt>csq</tt> is not <tt>null</tt>, behaves in
+     * exactly the same way as the invocation
+     *
+     * <pre>
+     *     out.append(csq.subSequence(start, end)) </pre>
+     *
+     * @param  csq
+     *         The character sequence from which a subsequence will be
+     *         appended.  If <tt>csq</tt> is <tt>null</tt>, then characters
+     *         will be appended as if <tt>csq</tt> contained the four
+     *         characters <tt>"null"</tt>.
+     *
+     * @param  start
+     *         The index of the first character in the subsequence
+     *
+     * @param  end
+     *         The index of the character following the last character in the
+     *         subsequence
+     *
+     * @return  A reference to this <tt>Appendable</tt>
+     *
+     * @throws  IndexOutOfBoundsException
+     *          If <tt>start</tt> or <tt>end</tt> are negative, <tt>start</tt>
+     *          is greater than <tt>end</tt>, or <tt>end</tt> is greater than
+     *          <tt>csq.length()</tt>
+     *
+     * @throws  IOException
+     *          If an I/O error occurs
+     */
+    Appendable append(CharSequence csq, int start, int end) throws IOException;
+
+    /**
+     * Appends the specified character to this <tt>Appendable</tt>.
+     *
+     * @param  c
+     *         The character to append
+     *
+     * @return  A reference to this <tt>Appendable</tt>
+     *
+     * @throws  IOException
+     *          If an I/O error occurs
+     */
+    Appendable append(char c) throws IOException;
+}