uk.co.cogitolearning.cogpar

Class ExpressionParser

java.lang.Object

uk.co.cogitolearning.cogpar.ExpressionParser

public class ExpressionParser
extends Object

A parser for mathematical expressions. The parser class defines a method parse() which takes a string and returns an ExpressionNode that holds a representation of the expression. Parsing is implemented in the form of a recursive descent parser.

Constructor Summary

Constructors

Constructor and Description
ExpressionParser()

Method Summary

Modifier and Type	Method and Description
ExpressionNode	parse(LinkedList<Token> tokens) Parse a mathematical expression in contained in a list of tokens and return an ExpressionNode.
ExpressionNode	parse(String expression) Parse a mathematical expression in a string and return an ExpressionNode.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ExpressionParser

public ExpressionParser()

Method Detail

parse

public ExpressionNode parse(String expression)

Parse a mathematical expression in a string and return an ExpressionNode. This is a convenience method that first converts the string into a linked list of tokens using the expression tokenizer provided by the Tokenizer class.

Parameters:

expression - the string holding the input

Returns:

the internal representation of the expression in form of an expression tree made out of ExpressionNode objects

parse

public ExpressionNode parse(LinkedList<Token> tokens)

Parse a mathematical expression in contained in a list of tokens and return an ExpressionNode.

Parameters:

tokens - a list of tokens holding the tokenized input

Returns:

the internal representation of the expression in form of an expression tree made out of ExpressionNode objects