/*
 * Copyright (c) 1996, 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.
 */
package sun.rmi.transport.proxy;

import java.io.*;

import sun.rmi.runtime.Log;

The HttpInputStream class assists the HttpSendSocket and HttpReceiveSocket classes by filtering out the header for the message as well as any data after its proper content length.
/** * The HttpInputStream class assists the HttpSendSocket and HttpReceiveSocket * classes by filtering out the header for the message as well as any * data after its proper content length. */
class HttpInputStream extends FilterInputStream {
bytes remaining to be read from proper content of message
/** bytes remaining to be read from proper content of message */
protected int bytesLeft;
bytes remaining to be read at time of last mark
/** bytes remaining to be read at time of last mark */
protected int bytesLeftAtMark;
Create new filter on a given input stream.
Params:
  • in – the InputStream to filter from
/** * Create new filter on a given input stream. * @param in the InputStream to filter from */
public HttpInputStream(InputStream in) throws IOException { super(in); if (in.markSupported()) in.mark(0); // prevent resetting back to old marks // pull out header, looking for content length DataInputStream dis = new DataInputStream(in); String key = "Content-length:".toLowerCase(); boolean contentLengthFound = false; String line; do { line = dis.readLine(); if (RMIMasterSocketFactory.proxyLog.isLoggable(Log.VERBOSE)) { RMIMasterSocketFactory.proxyLog.log(Log.VERBOSE, "received header line: \"" + line + "\""); } if (line == null) throw new EOFException(); if (line.toLowerCase().startsWith(key)) { if (contentLengthFound) { throw new IOException( "Multiple Content-length entries found."); } else { bytesLeft = Integer.parseInt(line.substring(key.length()).trim()); contentLengthFound = true; } } // The idea here is to go past the first blank line. // Some DataInputStream.readLine() documentation specifies that // it does include the line-terminating character(s) in the // returned string, but it actually doesn't, so we'll cover // all cases here... } while ((line.length() != 0) && (line.charAt(0) != '\r') && (line.charAt(0) != '\n')); if (!contentLengthFound || bytesLeft < 0) { // This really shouldn't happen, but if it does, shoud we fail?? // For now, just give up and let a whole lot of bytes through... bytesLeft = Integer.MAX_VALUE; } bytesLeftAtMark = bytesLeft; if (RMIMasterSocketFactory.proxyLog.isLoggable(Log.VERBOSE)) { RMIMasterSocketFactory.proxyLog.log(Log.VERBOSE, "content length: " + bytesLeft); } }
Returns the number of bytes that can be read with blocking. Make sure that this does not exceed the number of bytes remaining in the proper content of the message.
/** * Returns the number of bytes that can be read with blocking. * Make sure that this does not exceed the number of bytes remaining * in the proper content of the message. */
public int available() throws IOException { int bytesAvailable = in.available(); if (bytesAvailable > bytesLeft) bytesAvailable = bytesLeft; return bytesAvailable; }
Read a byte of data from the stream. Make sure that one is available from the proper content of the message, else -1 is returned to indicate to the user that the end of the stream has been reached.
/** * Read a byte of data from the stream. Make sure that one is available * from the proper content of the message, else -1 is returned to * indicate to the user that the end of the stream has been reached. */
public int read() throws IOException { if (bytesLeft > 0) { int data = in.read(); if (data != -1) -- bytesLeft; if (RMIMasterSocketFactory.proxyLog.isLoggable(Log.VERBOSE)) { RMIMasterSocketFactory.proxyLog.log(Log.VERBOSE, "received byte: '" + ((data & 0x7F) < ' ' ? " " : String.valueOf((char) data)) + "' " + data); } return data; } else { RMIMasterSocketFactory.proxyLog.log(Log.VERBOSE, "read past content length"); return -1; } } public int read(byte b[], int off, int len) throws IOException { if (bytesLeft == 0 && len > 0) { RMIMasterSocketFactory.proxyLog.log(Log.VERBOSE, "read past content length"); return -1; } if (len > bytesLeft) len = bytesLeft; int bytesRead = in.read(b, off, len); bytesLeft -= bytesRead; if (RMIMasterSocketFactory.proxyLog.isLoggable(Log.VERBOSE)) { RMIMasterSocketFactory.proxyLog.log(Log.VERBOSE, "read " + bytesRead + " bytes, " + bytesLeft + " remaining"); } return bytesRead; }
Mark the current position in the stream (for future calls to reset). Remember where we are within the proper content of the message, so that a reset method call can recreate our state properly.
Params:
  • readlimit – how many bytes can be read before mark becomes invalid
/** * Mark the current position in the stream (for future calls to reset). * Remember where we are within the proper content of the message, so * that a reset method call can recreate our state properly. * @param readlimit how many bytes can be read before mark becomes invalid */
public void mark(int readlimit) { in.mark(readlimit); if (in.markSupported()) bytesLeftAtMark = bytesLeft; }
Repositions the stream to the last marked position. Make sure to adjust our position within the proper content accordingly.
/** * Repositions the stream to the last marked position. Make sure to * adjust our position within the proper content accordingly. */
public void reset() throws IOException { in.reset(); bytesLeft = bytesLeftAtMark; }
Skips bytes of the stream. Make sure to adjust our position within the proper content accordingly.
Params:
  • n – number of bytes to be skipped
/** * Skips bytes of the stream. Make sure to adjust our * position within the proper content accordingly. * @param n number of bytes to be skipped */
public long skip(long n) throws IOException { if (n > bytesLeft) n = bytesLeft; long bytesSkipped = in.skip(n); bytesLeft -= bytesSkipped; return bytesSkipped; } }