Package jpicedt.format.input

Class DefaultParser

  • All Implemented Interfaces:
    ExpressionConstants, Parser
    public class DefaultParser
extends SequenceExpression
implements ExpressionConstants, Parser
    Default implementation of the Parser interface.

    This expression doesn't contains rules in itself. On the contrary, it simply lumps sub-trees together, each sub-tree containing grammar rules for a particular format, e.g. PsTricks, eepic,...

    Basically, this parser hold data using three objects :

    • an instance of util.Pool : this stores persistent data, and allow them to be shared by AbstractRegularExpression's across the whole parser tree.
    • an instance of util.Context : this holds the current state of the lexicographic analyser (line number, caret position, block boundaries, etc...)
    • an instance of AlternateExpression : this holds a reference to the various supported grammars by mixing them into a single tree.

    [Developpers] for those willing to add their own parser to the tree, simply write a new parser-tree whose root expression inherits from RootExpression, then add it to this parser by using the addGrammar method.

    Since:
    jpicedt 1.2
    Version:
    $Id: DefaultParser.java,v 1.8.2.1 2007/09/02 11:56:00 reynal Exp $
    Author:
    Sylvain Reynal

    • Field Detail

      • pool

        protected Pool pool
        a pool of primitive types and objects that may be shared by sub-expressions

      • context

        protected Context context
        holds information about the current parser state

    • Constructor Detail

      • DefaultParser

        public DefaultParser()
        Creates a new DefaultParser, and attach some grammar rules to it.
        Tree structure = (WhiteSpaceOrEOL & (headExp | notParsable))*
        where : headExp = Root1 | Root2 | Root3 ... (each RootX sub-tree representing a particular format).

        Note that with this current structure, sub-trees must NOT be mutually exclusive, ie it's ok with eepic and pstricks for instance (it wouldn't work with PDF and LaTeX, since once we've started with PDF, it wouldn't make sense trying to parse LaTeX commands...) ->

    • Method Detail

      • addGrammar

        public void addGrammar​(RootExpression root)
        Add a new sub-tree to this parser

      • getPool

        public Pool getPool()
        Return the pool containing variables shared across the grammar tree

      • parse

        public Drawing parse​(java.io.Reader reader)
              throws REParserException
        kicks off the parsing process
        Specified by:
        parse in interface Parser
        Returns:
        a new instance of a Drawing populated from the content of the given reader
        Throws:
        REParserException

      • toString

        public java.lang.String toString()
        Overrides:
        toString in class SequenceExpression
        Returns:
        a String representation of this Parser, i.e. global variables contents

      • main

        public static void main​(java.lang.String[] arg)
        parser standalone test
        Parameters:
        arg - [0] name of file to parse.