| /* |
| * Copyright (c) 1997, 2012, 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. |
| */ |
| |
| /* FROM mail.jar */ |
| package com.sun.xml.internal.org.jvnet.mimepull; |
| |
| import java.io.*; |
| |
| /** |
| * This class is to support reading CRLF terminated lines that |
| * contain only US-ASCII characters from an input stream. Provides |
| * functionality that is similar to the deprecated |
| * <code>DataInputStream.readLine()</code>. Expected use is to read |
| * lines as String objects from a RFC822 stream. |
| * |
| * It is implemented as a FilterInputStream, so one can just wrap |
| * this class around any input stream and read bytes from this filter. |
| * |
| * @author John Mani |
| */ |
| |
| final class LineInputStream extends FilterInputStream { |
| |
| private char[] lineBuffer = null; // reusable byte buffer |
| private static int MAX_INCR = 1024*1024; // 1MB |
| |
| public LineInputStream(InputStream in) { |
| super(in); |
| } |
| |
| /** |
| * Read a line containing only ASCII characters from the input |
| * stream. A line is terminated by a CR or NL or CR-NL sequence. |
| * A common error is a CR-CR-NL sequence, which will also terminate |
| * a line. |
| * The line terminator is not returned as part of the returned |
| * String. Returns null if no data is available. <p> |
| * |
| * This class is similar to the deprecated |
| * <code>DataInputStream.readLine()</code> |
| */ |
| public String readLine() throws IOException { |
| //InputStream in = this.in; |
| char[] buf = lineBuffer; |
| |
| if (buf == null) { |
| buf = lineBuffer = new char[128]; |
| } |
| |
| int c1; |
| int room = buf.length; |
| int offset = 0; |
| |
| while ((c1 = in.read()) != -1) { |
| if (c1 == '\n') { |
| break; |
| } else if (c1 == '\r') { |
| // Got CR, is the next char NL ? |
| boolean twoCRs = false; |
| if (in.markSupported()) { |
| in.mark(2); |
| } |
| int c2 = in.read(); |
| if (c2 == '\r') { // discard extraneous CR |
| twoCRs = true; |
| c2 = in.read(); |
| } |
| if (c2 != '\n') { |
| /* |
| * If the stream supports it (which we hope will always |
| * be the case), reset to after the first CR. Otherwise, |
| * we wrap a PushbackInputStream around the stream so we |
| * can unread the characters we don't need. The only |
| * problem with that is that the caller might stop |
| * reading from this LineInputStream, throw it away, |
| * and then start reading from the underlying stream. |
| * If that happens, the pushed back characters will be |
| * lost forever. |
| */ |
| if (in.markSupported()) { |
| in.reset(); |
| } else { |
| if (!(in instanceof PushbackInputStream)) { |
| in /*= this.in*/ = new PushbackInputStream(in, 2); |
| } |
| if (c2 != -1) { |
| ((PushbackInputStream)in).unread(c2); |
| } |
| if (twoCRs) { |
| ((PushbackInputStream)in).unread('\r'); |
| } |
| } |
| } |
| break; // outa here. |
| } |
| |
| // Not CR, NL or CR-NL ... |
| // .. Insert the byte into our byte buffer |
| if (--room < 0) { // No room, need to grow. |
| if (buf.length < MAX_INCR) { |
| buf = new char[buf.length * 2]; |
| } else { |
| buf = new char[buf.length + MAX_INCR]; |
| } |
| room = buf.length - offset - 1; |
| System.arraycopy(lineBuffer, 0, buf, 0, offset); |
| lineBuffer = buf; |
| } |
| buf[offset++] = (char)c1; |
| } |
| |
| if ((c1 == -1) && (offset == 0)) { |
| return null; |
| } |
| |
| return String.copyValueOf(buf, 0, offset); |
| } |
| } |