You are viewing a plain text version of this content. The canonical link for it is here.
Posted to server-dev@james.apache.org by no...@apache.org on 2003/06/05 01:12:12 UTC
cvs commit: jakarta-james/src/java/org/apache/james/util CRLFTerminatedReader.java
noel 2003/06/04 16:12:12
Added: src/java/org/apache/james/util CRLFTerminatedReader.java
Log:
New class that enforces the RFC mandated CRLF pairing in telnet-type protocols: SMTP (RFC 2821 #2.7.1), POP3, NNTP, etc.
Revision Changes Path
1.1 jakarta-james/src/java/org/apache/james/util/CRLFTerminatedReader.java
Index: CRLFTerminatedReader.java
===================================================================
/* ====================================================================
* The Apache Software License, Version 1.1
*
* Copyright (c) 2000-2003 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Apache", "Jakarta", "JAMES" and "Apache Software Foundation"
* must not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
* Portions of this software are based upon public domain software
* originally written at the National Center for Supercomputing Applications,
* University of Illinois, Urbana-Champaign.
*/
package org.apache.james.util;
import java.io.InputStream;
import java.io.BufferedReader;
import java.io.UnsupportedEncodingException;
import java.io.IOException;
import java.io.InputStreamReader;
/**
* A Reader for use with SMTP or other protocols in which lines
* must end with CRLF. Extends BufferedReader and overrides its
* readLine() method. The BufferedReader readLine() method cannot
* serve for SMTP because it ends lines with either CR or LF alone.
*/
public class CRLFTerminatedReader extends BufferedReader {
public class TerminationException extends IOException {
private int where;
public TerminationException(int where) {
super();
this.where = where;
}
public TerminationException(String s, int where) {
super(s);
this.where = where;
}
public int position() {
return where;
}
}
/**
* Constructs this CRLFTerminatedReader.
* @param in an InputStream
* @param charsetName the String name of a supported charset.
* "ASCII" is common here.
* @throws UnsupportedEncodingException if the named charset
* is not supported
*/
public CRLFTerminatedReader(InputStream in, String charsetName)
throws UnsupportedEncodingException {
super(new InputStreamReader(in, charsetName));
}
private StringBuffer lineBuffer = new StringBuffer();
private final int
EOF = -1,
CR = 13,
LF = 10;
private int tainted = -1;
/**
* Read a line of text which is terminated by CRLF. The concluding
* CRLF characters are not returned with the String, but if either CR
* or LF appears in the text in any other sequence it is returned
* in the String like any other character. Some characters at the
* end of the stream may be lost if they are in a "line" not
* terminated by CRLF.
*
* @return either a String containing the contents of a
* line which must end with CRLF, or null if the end of the
* stream has been reached, possibly discarding some characters
* in a line not terminated with CRLF.
* @throws IOException if an I/O error occurs.
*/
public String readLine() throws IOException{
//start with the StringBuffer empty
lineBuffer.delete(0, lineBuffer.length());
/* This boolean tells which state we are in,
* depending upon whether or not we got a CR
* in the preceding read().
*/
boolean cr_just_received = false;
while (true){
int inChar = read();
if (!cr_just_received){
//the most common case, somewhere before the end of a line
switch (inChar){
case CR : cr_just_received = true;
break;
case EOF : return null; // premature EOF -- discards data(?)
case LF : //the normal ending of a line
if (tainted == -1) tainted = lineBuffer.length();
// intentional fall-through
default : lineBuffer.append((char)inChar);
}
}else{
// CR has been received, we may be at end of line
switch (inChar){
case LF : // LF without a preceding CR
if (tainted != -1) {
int pos = tainted;
tainted = -1;
throw new TerminationException("\"bare\" CR or LF in data stream", pos);
}
return lineBuffer.toString();
case EOF : return null; // premature EOF -- discards data(?)
case CR : //we got two (or more) CRs in a row
if (tainted == -1) tainted = lineBuffer.length();
lineBuffer.append((char)CR);
break;
default : //we got some other character following a CR
if (tainted == -1) tainted = lineBuffer.length();
lineBuffer.append((char)CR);
lineBuffer.append((char)inChar);
cr_just_received = false;
}
}
}//while
}//method readLine()
}
---------------------------------------------------------------------
To unsubscribe, e-mail: james-dev-unsubscribe@jakarta.apache.org
For additional commands, e-mail: james-dev-help@jakarta.apache.org