alvinalexander.com | career | drupal | java | mac | mysql | perl | scala | uml | unix  

Tomcat example source code file (ChunkedInputFilter.java)

This example Tomcat source code file (ChunkedInputFilter.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Java - Tomcat tags/keywords

bytechunk, bytechunk, cr, crlf, crlf, encoding, inputbuffer, inputfilter, invalid, invalid, io, ioexception, ioexception, request, string

The Tomcat ChunkedInputFilter.java source code

/*
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

package org.apache.coyote.http11.filters;

import java.io.IOException;

import org.apache.tomcat.util.buf.ByteChunk;
import org.apache.tomcat.util.buf.HexUtils;

import org.apache.coyote.InputBuffer;
import org.apache.coyote.Request;
import org.apache.coyote.http11.Constants;
import org.apache.coyote.http11.InputFilter;

/**
 * Chunked input filter. Parses chunked data according to
 * <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.6.1">http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.6.1
* * @author Remy Maucherat * @author Filip Hanik */ public class ChunkedInputFilter implements InputFilter { // -------------------------------------------------------------- Constants protected static final String ENCODING_NAME = "chunked"; protected static final ByteChunk ENCODING = new ByteChunk(); // ----------------------------------------------------- Static Initializer static { ENCODING.setBytes(ENCODING_NAME.getBytes(), 0, ENCODING_NAME.length()); } // ----------------------------------------------------- Instance Variables /** * Next buffer in the pipeline. */ protected InputBuffer buffer; /** * Number of bytes remaining in the current chunk. */ protected int remaining = 0; /** * Position in the buffer. */ protected int pos = 0; /** * Last valid byte in the buffer. */ protected int lastValid = 0; /** * Read bytes buffer. */ protected byte[] buf = null; /** * Byte chunk used to read bytes. */ protected ByteChunk readChunk = new ByteChunk(); /** * Flag set to true when the end chunk has been read. */ protected boolean endChunk = false; /** * Flag set to true if the next call to doRead() must parse a CRLF pair * before doing anything else. */ protected boolean needCRLFParse = false; // ------------------------------------------------------------- Properties // ---------------------------------------------------- InputBuffer Methods /** * Read bytes. * * @return If the filter does request length control, this value is * significant; it should be the number of bytes consumed from the buffer, * up until the end of the current request body, or the buffer length, * whichever is greater. If the filter does not do request body length * control, the returned value should be -1. */ public int doRead(ByteChunk chunk, Request req) throws IOException { if (endChunk) return -1; if(needCRLFParse) { needCRLFParse = false; parseCRLF(); } if (remaining <= 0) { if (!parseChunkHeader()) { throw new IOException("Invalid chunk header"); } if (endChunk) { parseEndChunk(); return -1; } } int result = 0; if (pos >= lastValid) { readBytes(); } if (remaining > (lastValid - pos)) { result = lastValid - pos; remaining = remaining - result; chunk.setBytes(buf, pos, result); pos = lastValid; } else { result = remaining; chunk.setBytes(buf, pos, remaining); pos = pos + remaining; remaining = 0; //we need a CRLF if ((pos+1) >= lastValid) { //if we call parseCRLF we overrun the buffer here //so we defer it to the next call BZ 11117 needCRLFParse = true; } else { parseCRLF(); //parse the CRLF immediately } } return result; } // ---------------------------------------------------- InputFilter Methods /** * Read the content length from the request. */ public void setRequest(Request request) { } /** * End the current request. */ public long end() throws IOException { // Consume extra bytes : parse the stream until the end chunk is found while (doRead(readChunk, null) >= 0) { } // Return the number of extra bytes which were consumed return (lastValid - pos); } /** * Amount of bytes still available in a buffer. */ public int available() { return (lastValid - pos); } /** * Set the next buffer in the filter pipeline. */ public void setBuffer(InputBuffer buffer) { this.buffer = buffer; } /** * Make the filter ready to process the next request. */ public void recycle() { remaining = 0; pos = 0; lastValid = 0; endChunk = false; } /** * Return the name of the associated encoding; Here, the value is * "identity". */ public ByteChunk getEncodingName() { return ENCODING; } // ------------------------------------------------------ Protected Methods /** * Read bytes from the previous buffer. */ protected int readBytes() throws IOException { int nRead = buffer.doRead(readChunk, null); pos = readChunk.getStart(); lastValid = pos + nRead; buf = readChunk.getBytes(); return nRead; } /** * Parse the header of a chunk. * A chunk header can look like * A10CRLF * F23;chunk-extension to be ignoredCRLF * The letters before CRLF but after the trailer mark, must be valid hex digits, * we should not parse F23IAMGONNAMESSTHISUP34CRLF as a valid header * according to spec */ protected boolean parseChunkHeader() throws IOException { int result = 0; boolean eol = false; boolean readDigit = false; boolean trailer = false; while (!eol) { if (pos >= lastValid) { if (readBytes() <= 0) return false; } if (buf[pos] == Constants.CR) { } else if (buf[pos] == Constants.LF) { eol = true; } else if (buf[pos] == Constants.SEMI_COLON) { trailer = true; } else if (!trailer) { //don't read data after the trailer if (HexUtils.DEC[buf[pos]] != -1) { readDigit = true; result *= 16; result += HexUtils.DEC[buf[pos]]; } else { //we shouldn't allow invalid, non hex characters //in the chunked header return false; } } pos++; } if (!readDigit) return false; if (result == 0) endChunk = true; remaining = result; if (remaining < 0) return false; return true; } /** * Parse CRLF at end of chunk. */ protected boolean parseCRLF() throws IOException { boolean eol = false; boolean crfound = false; while (!eol) { if (pos >= lastValid) { if (readBytes() <= 0) throw new IOException("Invalid CRLF"); } if (buf[pos] == Constants.CR) { if (crfound) throw new IOException("Invalid CRLF, two CR characters encountered."); crfound = true; } else if (buf[pos] == Constants.LF) { if (!crfound) throw new IOException("Invalid CRLF, no CR character encountered."); eol = true; } else { throw new IOException("Invalid CRLF"); } pos++; } return true; } /** * Parse end chunk data. * FIXME: Handle trailers */ protected boolean parseEndChunk() throws IOException { return parseCRLF(); // FIXME } }

Other Tomcat examples (source code examples)

Here is a short list of links related to this Tomcat ChunkedInputFilter.java source code file:

... this post is sponsored by my books ...

#1 New Release!

FP Best Seller

 

new blog posts

 

Copyright 1998-2021 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.