michael@0: /*
michael@0:  * ====================================================================
michael@0:  * Licensed to the Apache Software Foundation (ASF) under one
michael@0:  * or more contributor license agreements.  See the NOTICE file
michael@0:  * distributed with this work for additional information
michael@0:  * regarding copyright ownership.  The ASF licenses this file
michael@0:  * to you under the Apache License, Version 2.0 (the
michael@0:  * "License"); you may not use this file except in compliance
michael@0:  * with the License.  You may obtain a copy of the License at
michael@0:  *
michael@0:  *   http://www.apache.org/licenses/LICENSE-2.0
michael@0:  *
michael@0:  * Unless required by applicable law or agreed to in writing,
michael@0:  * software distributed under the License is distributed on an
michael@0:  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
michael@0:  * KIND, either express or implied.  See the License for the
michael@0:  * specific language governing permissions and limitations
michael@0:  * under the License.
michael@0:  * ====================================================================
michael@0:  *
michael@0:  * This software consists of voluntary contributions made by many
michael@0:  * individuals on behalf of the Apache Software Foundation.  For more
michael@0:  * information on the Apache Software Foundation, please see
michael@0:  * <http://www.apache.org/>.
michael@0:  *
michael@0:  */
michael@0: 
michael@0: package ch.boye.httpclientandroidlib.message;
michael@0: 
michael@0: import ch.boye.httpclientandroidlib.HttpVersion;
michael@0: import ch.boye.httpclientandroidlib.ProtocolVersion;
michael@0: import ch.boye.httpclientandroidlib.ParseException;
michael@0: import ch.boye.httpclientandroidlib.RequestLine;
michael@0: import ch.boye.httpclientandroidlib.StatusLine;
michael@0: import ch.boye.httpclientandroidlib.Header;
michael@0: import ch.boye.httpclientandroidlib.protocol.HTTP;
michael@0: import ch.boye.httpclientandroidlib.util.CharArrayBuffer;
michael@0: 
michael@0: /**
michael@0:  * Basic parser for lines in the head section of an HTTP message.
michael@0:  * There are individual methods for parsing a request line, a
michael@0:  * status line, or a header line.
michael@0:  * The lines to parse are passed in memory, the parser does not depend
michael@0:  * on any specific IO mechanism.
michael@0:  * Instances of this class are stateless and thread-safe.
michael@0:  * Derived classes MUST maintain these properties.
michael@0:  *
michael@0:  * <p>
michael@0:  * Note: This class was created by refactoring parsing code located in
michael@0:  * various other classes. The author tags from those other classes have
michael@0:  * been replicated here, although the association with the parsing code
michael@0:  * taken from there has not been traced.
michael@0:  * </p>
michael@0:  *
michael@0:  * @since 4.0
michael@0:  */
michael@0: public class BasicLineParser implements LineParser {
michael@0: 
michael@0:     /**
michael@0:      * A default instance of this class, for use as default or fallback.
michael@0:      * Note that {@link BasicLineParser} is not a singleton, there can
michael@0:      * be many instances of the class itself and of derived classes.
michael@0:      * The instance here provides non-customized, default behavior.
michael@0:      */
michael@0:     public final static BasicLineParser DEFAULT = new BasicLineParser();
michael@0: 
michael@0: 
michael@0:     /**
michael@0:      * A version of the protocol to parse.
michael@0:      * The version is typically not relevant, but the protocol name.
michael@0:      */
michael@0:     protected final ProtocolVersion protocol;
michael@0: 
michael@0: 
michael@0:     /**
michael@0:      * Creates a new line parser for the given HTTP-like protocol.
michael@0:      *
michael@0:      * @param proto     a version of the protocol to parse, or
michael@0:      *                  <code>null</code> for HTTP. The actual version
michael@0:      *                  is not relevant, only the protocol name.
michael@0:      */
michael@0:     public BasicLineParser(ProtocolVersion proto) {
michael@0:         if (proto == null) {
michael@0:             proto = HttpVersion.HTTP_1_1;
michael@0:         }
michael@0:         this.protocol = proto;
michael@0:     }
michael@0: 
michael@0: 
michael@0:     /**
michael@0:      * Creates a new line parser for HTTP.
michael@0:      */
michael@0:     public BasicLineParser() {
michael@0:         this(null);
michael@0:     }
michael@0: 
michael@0: 
michael@0:     public final static
michael@0:         ProtocolVersion parseProtocolVersion(String value,
michael@0:                                              LineParser parser)
michael@0:         throws ParseException {
michael@0: 
michael@0:         if (value == null) {
michael@0:             throw new IllegalArgumentException
michael@0:                 ("Value to parse may not be null.");
michael@0:         }
michael@0: 
michael@0:         if (parser == null)
michael@0:             parser = BasicLineParser.DEFAULT;
michael@0: 
michael@0:         CharArrayBuffer buffer = new CharArrayBuffer(value.length());
michael@0:         buffer.append(value);
michael@0:         ParserCursor cursor = new ParserCursor(0, value.length());
michael@0:         return parser.parseProtocolVersion(buffer, cursor);
michael@0:     }
michael@0: 
michael@0: 
michael@0:     // non-javadoc, see interface LineParser
michael@0:     public ProtocolVersion parseProtocolVersion(final CharArrayBuffer buffer,
michael@0:                                                 final ParserCursor cursor)
michael@0:         throws ParseException {
michael@0: 
michael@0:         if (buffer == null) {
michael@0:             throw new IllegalArgumentException("Char array buffer may not be null");
michael@0:         }
michael@0:         if (cursor == null) {
michael@0:             throw new IllegalArgumentException("Parser cursor may not be null");
michael@0:         }
michael@0: 
michael@0:         final String protoname = this.protocol.getProtocol();
michael@0:         final int protolength  = protoname.length();
michael@0: 
michael@0:         int indexFrom = cursor.getPos();
michael@0:         int indexTo = cursor.getUpperBound();
michael@0: 
michael@0:         skipWhitespace(buffer, cursor);
michael@0: 
michael@0:         int i = cursor.getPos();
michael@0: 
michael@0:         // long enough for "HTTP/1.1"?
michael@0:         if (i + protolength + 4 > indexTo) {
michael@0:             throw new ParseException
michael@0:                 ("Not a valid protocol version: " +
michael@0:                  buffer.substring(indexFrom, indexTo));
michael@0:         }
michael@0: 
michael@0:         // check the protocol name and slash
michael@0:         boolean ok = true;
michael@0:         for (int j=0; ok && (j<protolength); j++) {
michael@0:             ok = (buffer.charAt(i+j) == protoname.charAt(j));
michael@0:         }
michael@0:         if (ok) {
michael@0:             ok = (buffer.charAt(i+protolength) == '/');
michael@0:         }
michael@0:         if (!ok) {
michael@0:             throw new ParseException
michael@0:                 ("Not a valid protocol version: " +
michael@0:                  buffer.substring(indexFrom, indexTo));
michael@0:         }
michael@0: 
michael@0:         i += protolength+1;
michael@0: 
michael@0:         int period = buffer.indexOf('.', i, indexTo);
michael@0:         if (period == -1) {
michael@0:             throw new ParseException
michael@0:                 ("Invalid protocol version number: " +
michael@0:                  buffer.substring(indexFrom, indexTo));
michael@0:         }
michael@0:         int major;
michael@0:         try {
michael@0:             major = Integer.parseInt(buffer.substringTrimmed(i, period));
michael@0:         } catch (NumberFormatException e) {
michael@0:             throw new ParseException
michael@0:                 ("Invalid protocol major version number: " +
michael@0:                  buffer.substring(indexFrom, indexTo));
michael@0:         }
michael@0:         i = period + 1;
michael@0: 
michael@0:         int blank = buffer.indexOf(' ', i, indexTo);
michael@0:         if (blank == -1) {
michael@0:             blank = indexTo;
michael@0:         }
michael@0:         int minor;
michael@0:         try {
michael@0:             minor = Integer.parseInt(buffer.substringTrimmed(i, blank));
michael@0:         } catch (NumberFormatException e) {
michael@0:             throw new ParseException(
michael@0:                 "Invalid protocol minor version number: " +
michael@0:                 buffer.substring(indexFrom, indexTo));
michael@0:         }
michael@0: 
michael@0:         cursor.updatePos(blank);
michael@0: 
michael@0:         return createProtocolVersion(major, minor);
michael@0: 
michael@0:     } // parseProtocolVersion
michael@0: 
michael@0: 
michael@0:     /**
michael@0:      * Creates a protocol version.
michael@0:      * Called from {@link #parseProtocolVersion}.
michael@0:      *
michael@0:      * @param major     the major version number, for example 1 in HTTP/1.0
michael@0:      * @param minor     the minor version number, for example 0 in HTTP/1.0
michael@0:      *
michael@0:      * @return  the protocol version
michael@0:      */
michael@0:     protected ProtocolVersion createProtocolVersion(int major, int minor) {
michael@0:         return protocol.forVersion(major, minor);
michael@0:     }
michael@0: 
michael@0: 
michael@0: 
michael@0:     // non-javadoc, see interface LineParser
michael@0:     public boolean hasProtocolVersion(final CharArrayBuffer buffer,
michael@0:                                       final ParserCursor cursor) {
michael@0: 
michael@0:         if (buffer == null) {
michael@0:             throw new IllegalArgumentException("Char array buffer may not be null");
michael@0:         }
michael@0:         if (cursor == null) {
michael@0:             throw new IllegalArgumentException("Parser cursor may not be null");
michael@0:         }
michael@0:         int index = cursor.getPos();
michael@0: 
michael@0:         final String protoname = this.protocol.getProtocol();
michael@0:         final int  protolength = protoname.length();
michael@0: 
michael@0:         if (buffer.length() < protolength+4)
michael@0:             return false; // not long enough for "HTTP/1.1"
michael@0: 
michael@0:         if (index < 0) {
michael@0:             // end of line, no tolerance for trailing whitespace
michael@0:             // this works only for single-digit major and minor version
michael@0:             index = buffer.length() -4 -protolength;
michael@0:         } else if (index == 0) {
michael@0:             // beginning of line, tolerate leading whitespace
michael@0:             while ((index < buffer.length()) &&
michael@0:                     HTTP.isWhitespace(buffer.charAt(index))) {
michael@0:                  index++;
michael@0:              }
michael@0:         } // else within line, don't tolerate whitespace
michael@0: 
michael@0: 
michael@0:         if (index + protolength + 4 > buffer.length())
michael@0:             return false;
michael@0: 
michael@0: 
michael@0:         // just check protocol name and slash, no need to analyse the version
michael@0:         boolean ok = true;
michael@0:         for (int j=0; ok && (j<protolength); j++) {
michael@0:             ok = (buffer.charAt(index+j) == protoname.charAt(j));
michael@0:         }
michael@0:         if (ok) {
michael@0:             ok = (buffer.charAt(index+protolength) == '/');
michael@0:         }
michael@0: 
michael@0:         return ok;
michael@0:     }
michael@0: 
michael@0: 
michael@0: 
michael@0:     public final static
michael@0:         RequestLine parseRequestLine(final String value,
michael@0:                                      LineParser parser)
michael@0:         throws ParseException {
michael@0: 
michael@0:         if (value == null) {
michael@0:             throw new IllegalArgumentException
michael@0:                 ("Value to parse may not be null.");
michael@0:         }
michael@0: 
michael@0:         if (parser == null)
michael@0:             parser = BasicLineParser.DEFAULT;
michael@0: 
michael@0:         CharArrayBuffer buffer = new CharArrayBuffer(value.length());
michael@0:         buffer.append(value);
michael@0:         ParserCursor cursor = new ParserCursor(0, value.length());
michael@0:         return parser.parseRequestLine(buffer, cursor);
michael@0:     }
michael@0: 
michael@0: 
michael@0:     /**
michael@0:      * Parses a request line.
michael@0:      *
michael@0:      * @param buffer    a buffer holding the line to parse
michael@0:      *
michael@0:      * @return  the parsed request line
michael@0:      *
michael@0:      * @throws ParseException        in case of a parse error
michael@0:      */
michael@0:     public RequestLine parseRequestLine(final CharArrayBuffer buffer,
michael@0:                                         final ParserCursor cursor)
michael@0:         throws ParseException {
michael@0: 
michael@0:         if (buffer == null) {
michael@0:             throw new IllegalArgumentException("Char array buffer may not be null");
michael@0:         }
michael@0:         if (cursor == null) {
michael@0:             throw new IllegalArgumentException("Parser cursor may not be null");
michael@0:         }
michael@0: 
michael@0:         int indexFrom = cursor.getPos();
michael@0:         int indexTo = cursor.getUpperBound();
michael@0: 
michael@0:         try {
michael@0:             skipWhitespace(buffer, cursor);
michael@0:             int i = cursor.getPos();
michael@0: 
michael@0:             int blank = buffer.indexOf(' ', i, indexTo);
michael@0:             if (blank < 0) {
michael@0:                 throw new ParseException("Invalid request line: " +
michael@0:                         buffer.substring(indexFrom, indexTo));
michael@0:             }
michael@0:             String method = buffer.substringTrimmed(i, blank);
michael@0:             cursor.updatePos(blank);
michael@0: 
michael@0:             skipWhitespace(buffer, cursor);
michael@0:             i = cursor.getPos();
michael@0: 
michael@0:             blank = buffer.indexOf(' ', i, indexTo);
michael@0:             if (blank < 0) {
michael@0:                 throw new ParseException("Invalid request line: " +
michael@0:                         buffer.substring(indexFrom, indexTo));
michael@0:             }
michael@0:             String uri = buffer.substringTrimmed(i, blank);
michael@0:             cursor.updatePos(blank);
michael@0: 
michael@0:             ProtocolVersion ver = parseProtocolVersion(buffer, cursor);
michael@0: 
michael@0:             skipWhitespace(buffer, cursor);
michael@0:             if (!cursor.atEnd()) {
michael@0:                 throw new ParseException("Invalid request line: " +
michael@0:                         buffer.substring(indexFrom, indexTo));
michael@0:             }
michael@0: 
michael@0:             return createRequestLine(method, uri, ver);
michael@0:         } catch (IndexOutOfBoundsException e) {
michael@0:             throw new ParseException("Invalid request line: " +
michael@0:                                      buffer.substring(indexFrom, indexTo));
michael@0:         }
michael@0:     } // parseRequestLine
michael@0: 
michael@0: 
michael@0:     /**
michael@0:      * Instantiates a new request line.
michael@0:      * Called from {@link #parseRequestLine}.
michael@0:      *
michael@0:      * @param method    the request method
michael@0:      * @param uri       the requested URI
michael@0:      * @param ver       the protocol version
michael@0:      *
michael@0:      * @return  a new status line with the given data
michael@0:      */
michael@0:     protected RequestLine createRequestLine(final String method,
michael@0:                                             final String uri,
michael@0:                                             final ProtocolVersion ver) {
michael@0:         return new BasicRequestLine(method, uri, ver);
michael@0:     }
michael@0: 
michael@0: 
michael@0: 
michael@0:     public final static
michael@0:         StatusLine parseStatusLine(final String value,
michael@0:                                    LineParser parser)
michael@0:         throws ParseException {
michael@0: 
michael@0:         if (value == null) {
michael@0:             throw new IllegalArgumentException
michael@0:                 ("Value to parse may not be null.");
michael@0:         }
michael@0: 
michael@0:         if (parser == null)
michael@0:             parser = BasicLineParser.DEFAULT;
michael@0: 
michael@0:         CharArrayBuffer buffer = new CharArrayBuffer(value.length());
michael@0:         buffer.append(value);
michael@0:         ParserCursor cursor = new ParserCursor(0, value.length());
michael@0:         return parser.parseStatusLine(buffer, cursor);
michael@0:     }
michael@0: 
michael@0: 
michael@0:     // non-javadoc, see interface LineParser
michael@0:     public StatusLine parseStatusLine(final CharArrayBuffer buffer,
michael@0:                                       final ParserCursor cursor)
michael@0:         throws ParseException {
michael@0: 
michael@0:         if (buffer == null) {
michael@0:             throw new IllegalArgumentException("Char array buffer may not be null");
michael@0:         }
michael@0:         if (cursor == null) {
michael@0:             throw new IllegalArgumentException("Parser cursor may not be null");
michael@0:         }
michael@0: 
michael@0:         int indexFrom = cursor.getPos();
michael@0:         int indexTo = cursor.getUpperBound();
michael@0: 
michael@0:         try {
michael@0:             // handle the HTTP-Version
michael@0:             ProtocolVersion ver = parseProtocolVersion(buffer, cursor);
michael@0: 
michael@0:             // handle the Status-Code
michael@0:             skipWhitespace(buffer, cursor);
michael@0:             int i = cursor.getPos();
michael@0: 
michael@0:             int blank = buffer.indexOf(' ', i, indexTo);
michael@0:             if (blank < 0) {
michael@0:                 blank = indexTo;
michael@0:             }
michael@0:             int statusCode = 0;
michael@0:             String s = buffer.substringTrimmed(i, blank);
michael@0:             for (int j = 0; j < s.length(); j++) {
michael@0:                 if (!Character.isDigit(s.charAt(j))) {
michael@0:                     throw new ParseException(
michael@0:                             "Status line contains invalid status code: "
michael@0:                             + buffer.substring(indexFrom, indexTo));
michael@0:                 }
michael@0:             }
michael@0:             try {
michael@0:                 statusCode = Integer.parseInt(s);
michael@0:             } catch (NumberFormatException e) {
michael@0:                 throw new ParseException(
michael@0:                         "Status line contains invalid status code: "
michael@0:                         + buffer.substring(indexFrom, indexTo));
michael@0:             }
michael@0:             //handle the Reason-Phrase
michael@0:             i = blank;
michael@0:             String reasonPhrase = null;
michael@0:             if (i < indexTo) {
michael@0:                 reasonPhrase = buffer.substringTrimmed(i, indexTo);
michael@0:             } else {
michael@0:                 reasonPhrase = "";
michael@0:             }
michael@0:             return createStatusLine(ver, statusCode, reasonPhrase);
michael@0: 
michael@0:         } catch (IndexOutOfBoundsException e) {
michael@0:             throw new ParseException("Invalid status line: " +
michael@0:                                      buffer.substring(indexFrom, indexTo));
michael@0:         }
michael@0:     } // parseStatusLine
michael@0: 
michael@0: 
michael@0:     /**
michael@0:      * Instantiates a new status line.
michael@0:      * Called from {@link #parseStatusLine}.
michael@0:      *
michael@0:      * @param ver       the protocol version
michael@0:      * @param status    the status code
michael@0:      * @param reason    the reason phrase
michael@0:      *
michael@0:      * @return  a new status line with the given data
michael@0:      */
michael@0:     protected StatusLine createStatusLine(final ProtocolVersion ver,
michael@0:                                           final int status,
michael@0:                                           final String reason) {
michael@0:         return new BasicStatusLine(ver, status, reason);
michael@0:     }
michael@0: 
michael@0: 
michael@0: 
michael@0:     public final static
michael@0:         Header parseHeader(final String value,
michael@0:                            LineParser parser)
michael@0:         throws ParseException {
michael@0: 
michael@0:         if (value == null) {
michael@0:             throw new IllegalArgumentException
michael@0:                 ("Value to parse may not be null");
michael@0:         }
michael@0: 
michael@0:         if (parser == null)
michael@0:             parser = BasicLineParser.DEFAULT;
michael@0: 
michael@0:         CharArrayBuffer buffer = new CharArrayBuffer(value.length());
michael@0:         buffer.append(value);
michael@0:         return parser.parseHeader(buffer);
michael@0:     }
michael@0: 
michael@0: 
michael@0:     // non-javadoc, see interface LineParser
michael@0:     public Header parseHeader(CharArrayBuffer buffer)
michael@0:         throws ParseException {
michael@0: 
michael@0:         // the actual parser code is in the constructor of BufferedHeader
michael@0:         return new BufferedHeader(buffer);
michael@0:     }
michael@0: 
michael@0: 
michael@0:     /**
michael@0:      * Helper to skip whitespace.
michael@0:      */
michael@0:     protected void skipWhitespace(final CharArrayBuffer buffer, final ParserCursor cursor) {
michael@0:         int pos = cursor.getPos();
michael@0:         int indexTo = cursor.getUpperBound();
michael@0:         while ((pos < indexTo) &&
michael@0:                HTTP.isWhitespace(buffer.charAt(pos))) {
michael@0:             pos++;
michael@0:         }
michael@0:         cursor.updatePos(pos);
michael@0:     }
michael@0: 
michael@0: } // class BasicLineParser