Java tutorial
/* * Copyright (c) 2003, 2004, Oracle and/or its affiliates. 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. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.lang; import java.io.IOException; /** * An object to which {@code char} sequences and values can be appended. The * {@code Appendable} 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 {@code char} 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 {@code Appendable}. * * <p> Depending on which class implements the character sequence * {@code csq}, the entire sequence may not be appended. For * instance, if {@code csq} 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 {@code csq} is * {@code null}, then the four characters {@code "null"} are * appended to this Appendable. * * @return A reference to this {@code Appendable} * * @throws IOException * If an I/O error occurs */ Appendable append(CharSequence csq) throws IOException; /** * Appends a subsequence of the specified character sequence to this * {@code Appendable}. * * <p> An invocation of this method of the form {@code out.append(csq, start, end)} * when {@code csq} is not {@code null}, 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 {@code csq} is {@code null}, then characters * will be appended as if {@code csq} contained the four * characters {@code "null"}. * * @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 {@code Appendable} * * @throws IndexOutOfBoundsException * If {@code start} or {@code end} are negative, {@code start} * is greater than {@code end}, or {@code end} is greater than * {@code csq.length()} * * @throws IOException * If an I/O error occurs */ Appendable append(CharSequence csq, int start, int end) throws IOException; /** * Appends the specified character to this {@code Appendable}. * * @param c * The character to append * * @return A reference to this {@code Appendable} * * @throws IOException * If an I/O error occurs */ Appendable append(char c) throws IOException; }