Java tutorial
/* * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. * * Copyright (c) 1997-2017 Oracle and/or its affiliates. All rights reserved. * * The contents of this file are subject to the terms of either the GNU * General Public License Version 2 only ("GPL") or the Common Development * and Distribution License("CDDL") (collectively, the "License"). You * may not use this file except in compliance with the License. You can * obtain a copy of the License at * https://oss.oracle.com/licenses/CDDL+GPL-1.1 * or LICENSE.txt. See the License for the specific * language governing permissions and limitations under the License. * * When distributing the software, include this License Header Notice in each * file and include the License file at LICENSE.txt. * * GPL Classpath Exception: * Oracle designates this particular file as subject to the "Classpath" * exception as provided by Oracle in the GPL Version 2 section of the License * file that accompanied this code. * * Modifications: * If applicable, add the following below the License Header, with the fields * enclosed by brackets [] replaced by your own identifying information: * "Portions Copyright [year] [name of copyright owner]" * * Contributor(s): * If you wish your version of this file to be governed by only the CDDL or * only the GPL Version 2, indicate your decision by adding "[Contributor] * elects to include this software in this distribution under the [CDDL or GPL * Version 2] license." If you don't indicate a single choice of license, a * recipient has the option to distribute your version of this file under * either the CDDL, the GPL Version 2 or to extend the choice of license to * its licensees as provided above. However, if you add GPL Version 2 code * and therefore, elected the GPL Version 2 license, then the option applies * only if the new code is made subject to such option by the copyright * holder. */ package javax.mail.internet; import java.io.*; /** * An InputStream that is backed by data that can be shared by multiple * readers may implement this interface. This allows users of such an * InputStream to determine the current position in the InputStream, and * to create new InputStreams representing a subset of the data in the * original InputStream. The new InputStream will access the same * underlying data as the original, without copying the data. <p> * * Note that implementations of this interface must ensure that the * <code>close</code> method does not close any underlying stream * that might be shared by multiple instances of <code>SharedInputStream</code> * until all shared instances have been closed. * * @author Bill Shannon * @since JavaMail 1.2 */ public interface SharedInputStream { /** * Return the current position in the InputStream, as an * offset from the beginning of the InputStream. * * @return the current position */ public long getPosition(); /** * Return a new InputStream representing a subset of the data * from this InputStream, starting at <code>start</code> (inclusive) * up to <code>end</code> (exclusive). <code>start</code> must be * non-negative. If <code>end</code> is -1, the new stream ends * at the same place as this stream. The returned InputStream * will also implement the SharedInputStream interface. * * @param start the starting position * @param end the ending position + 1 * @return the new stream */ public InputStream newStream(long start, long end); }