jspreader.java

业界著名的tomcat服务器的最新6.0的源代码。

     *         before the search string) if found, <strong>null</strong>
     *         otherwise.
     */
    Mark skipUntil(String limit) throws JasperException {
        Mark ret = null;
        int limlen = limit.length();
        int ch;

    skip:
        for (ret = mark(), ch = nextChar() ; ch != -1 ;
                 ret = mark(), ch = nextChar()) {
            if (ch == limit.charAt(0)) {
                Mark restart = mark();
                for (int i = 1 ; i < limlen ; i++) {
                    if (peekChar() == limit.charAt(i))
                        nextChar();
                    else {
                        reset(restart);
                        continue skip;
                    }
                }
                return ret;
            }
        }
        return null;
    }

    /**
     * Skip until the given string is matched in the stream, but ignoring
     * chars initially escaped by a '\'.
     * When returned, the context is positioned past the end of the match.
     *
     * @param s The String to match.
     * @return A non-null <code>Mark</code> instance (positioned immediately
     *         before the search string) if found, <strong>null</strong>
     *         otherwise.
     */
    Mark skipUntilIgnoreEsc(String limit) throws JasperException {
        Mark ret = null;
        int limlen = limit.length();
        int ch;
        int prev = 'x';        // Doesn't matter
        
    skip:
        for (ret = mark(), ch = nextChar() ; ch != -1 ;
                 ret = mark(), prev = ch, ch = nextChar()) {            
            if (ch == '\\' && prev == '\\') {
                ch = 0;                // Double \ is not an escape char anymore
            }
            else if (ch == limit.charAt(0) && prev != '\\') {
                for (int i = 1 ; i < limlen ; i++) {
                    if (peekChar() == limit.charAt(i))
                        nextChar();
                    else
                        continue skip;
                }
                return ret;
            }
        }
        return null;
    }
    
    /**
     * Skip until the given end tag is matched in the stream.
     * When returned, the context is positioned past the end of the tag.
     *
     * @param tag The name of the tag whose ETag (</tag>) to match.
     * @return A non-null <code>Mark</code> instance (positioned immediately
     *               before the ETag) if found, <strong>null</strong> otherwise.
     */
    Mark skipUntilETag(String tag) throws JasperException {
        Mark ret = skipUntil("</" + tag);
        if (ret != null) {
            skipSpaces();
            if (nextChar() != '>')
                ret = null;
        }
        return ret;
    }

    final boolean isSpace() throws JasperException {
        // Note: If this logic changes, also update Node.TemplateText.rtrim()
        return peekChar() <= ' ';
    }

    /**
     * Parse a space delimited token.
     * If quoted the token will consume all characters up to a matching quote,
     * otherwise, it consumes up to the first delimiter character.
     *
     * @param quoted If <strong>true</strong> accept quoted strings.
     */
    String parseToken(boolean quoted) throws JasperException {
        StringBuffer stringBuffer = new StringBuffer();
        skipSpaces();
        stringBuffer.setLength(0);
        
        if (!hasMoreInput()) {
            return "";
        }

        int ch = peekChar();
        
        if (quoted) {
            if (ch == '"' || ch == '\'') {

                char endQuote = ch == '"' ? '"' : '\'';
                // Consume the open quote: 
                ch = nextChar();
                for (ch = nextChar(); ch != -1 && ch != endQuote;
                         ch = nextChar()) {
                    if (ch == '\\') 
                        ch = nextChar();
                    stringBuffer.append((char) ch);
                }
                // Check end of quote, skip closing quote:
                if (ch == -1) {
                    err.jspError(mark(), "jsp.error.quotes.unterminated");
                }
            } else {
                err.jspError(mark(), "jsp.error.attr.quoted");
            }
        } else {
            if (!isDelimiter()) {
                // Read value until delimiter is found:
                do {
                    ch = nextChar();
                    // Take care of the quoting here.
                    if (ch == '\\') {
                        if (peekChar() == '"' || peekChar() == '\'' ||
                               peekChar() == '>' || peekChar() == '%')
                            ch = nextChar();
                    }
                    stringBuffer.append((char) ch);
                } while (!isDelimiter());
            }
        }

        return stringBuffer.toString();
    }

    void setSingleFile(boolean val) {
        singleFile = val;
    }


    /**
     * Gets the URL for the given path name.
     *
     * @param path Path name
     *
     * @return URL for the given path name.
     *
     * @exception MalformedURLException if the path name is not given in 
     * the correct form
     */
    URL getResource(String path) throws MalformedURLException {
        return context.getResource(path);
    }


    /**
     * Parse utils - Is current character a token delimiter ?
     * Delimiters are currently defined to be =, &gt;, &lt;, ", and ' or any
     * any space character as defined by <code>isSpace</code>.
     *
     * @return A boolean.
     */
    private boolean isDelimiter() throws JasperException {
        if (! isSpace()) {
            int ch = peekChar();
            // Look for a single-char work delimiter:
            if (ch == '=' || ch == '>' || ch == '"' || ch == '\''
                    || ch == '/') {
                return true;
            }
            // Look for an end-of-comment or end-of-tag:                
            if (ch == '-') {
                Mark mark = mark();
                if (((ch = nextChar()) == '>')
                        || ((ch == '-') && (nextChar() == '>'))) {
                    reset(mark);
                    return true;
                } else {
                    reset(mark);
                    return false;
                }
            }
            return false;
        } else {
            return true;
        }
    }

    /**
     * Register a new source file.
     * This method is used to implement file inclusion. Each included file
     * gets a unique identifier (which is the index in the array of source
     * files).
     *
     * @return The index of the now registered file.
     */
    private int registerSourceFile(final String file) {
        if (sourceFiles.contains(file)) {
            return -1;
        }

        sourceFiles.add(file);
        this.size++;

        return sourceFiles.size() - 1;
    }
    

    /**
     * Unregister the source file.
     * This method is used to implement file inclusion. Each included file
     * gets a uniq identifier (which is the index in the array of source
     * files).
     *
     * @return The index of the now registered file.
     */
    private int unregisterSourceFile(final String file) {
        if (!sourceFiles.contains(file)) {
            return -1;
        }

        sourceFiles.remove(file);
        this.size--;
        return sourceFiles.size() - 1;
    }

    /**
     * Push a file (and its associated Stream) on the file stack.  THe
     * current position in the current file is remembered.
     */
    private void pushFile(String file, String encoding, 
                           InputStreamReader reader) 
                throws JasperException, FileNotFoundException {

        // Register the file
        String longName = file;

        int fileid = registerSourceFile(longName);

        if (fileid == -1) {
            // Bugzilla 37407: http://issues.apache.org/bugzilla/show_bug.cgi?id=37407
            if(reader != null) {
                try {
                    reader.close();
                } catch (Exception any) {
                    if(log.isDebugEnabled()) {
                        log.debug("Exception closing reader: ", any);
                    }
                }
            }

            err.jspError("jsp.error.file.already.registered", file);
        }

        currFileId = fileid;

        try {
            CharArrayWriter caw = new CharArrayWriter();
            char buf[] = new char[1024];
            for (int i = 0 ; (i = reader.read(buf)) != -1 ;)
                caw.write(buf, 0, i);
            caw.close();
            if (current == null) {
                current = new Mark(this, caw.toCharArray(), fileid, 
                                   getFile(fileid), master, encoding);
            } else {
                current.pushStream(caw.toCharArray(), fileid, getFile(fileid),
                                   longName, encoding);
            }
        } catch (Throwable ex) {
            log.error("Exception parsing file ", ex);
            // Pop state being constructed:
            popFile();
            err.jspError("jsp.error.file.cannot.read", file);
        } finally {
            if (reader != null) {
                try {
                    reader.close();
                } catch (Exception any) {
                    if(log.isDebugEnabled()) {
                        log.debug("Exception closing reader: ", any);
                    }
                }
            }
        }
    }

    /**
     * Pop a file from the file stack.  The field "current" is retored
     * to the value to point to the previous files, if any, and is set
     * to null otherwise.
     * @return true is there is a previous file on the stack.
     *         false otherwise.
     */
    private boolean popFile() throws JasperException {

        // Is stack created ? (will happen if the Jsp file we're looking at is
        // missing.
        if (current == null || currFileId < 0) {
            return false;
        }

        // Restore parser state:
        String fName = getFile(currFileId);
        currFileId = unregisterSourceFile(fName);
        if (currFileId < -1) {
            err.jspError("jsp.error.file.not.registered", fName);
        }

        Mark previous = current.popStream();
        if (previous != null) {
            master = current.baseDir;
            current = previous;
            return true;
        }
        // Note that although the current file is undefined here, "current"
        // is not set to null just for convience, for it maybe used to
        // set the current (undefined) position.
        return false;
    }
}