Class Parser

java.lang.Object
  |
  +--Parser

public class Parser

extends java.lang.Object

A parser for RETRAN-2.

Version:

2.0 Oct 2003

Author:

Paul Bailes, modified from another parser by Phil Cook, Ned Martin, modified 02-Nov-2003

Field Summary

static int	COMMA_SYM
private java.lang.String	currentName
private int	currentNumber
private int	currentSym
static int	DIV_SYM
static int	ELSE_SYM
static int	EQEQ_SYM
static int	EQUAL_SYM
static int	GE_SYM
static int	GT_SYM
static int	IF_SYM
static int	LE_SYM
static int	LEFT_PAREN_SYM
static int	LT_SYM
static int	MINUS_SYM
static int	MULT_SYM
static int	NAME_SYM
static int	NEQ_SYM
static int	NO_SYM
static int	NUMBER_SYM
static int	PLUS_SYM
static int	RIGHT_PAREN_SYM
private Scanner	scanner
static int	SEMICOLON_SYM
static int	THEN_SYM
static int	WHERE_SYM

Constructor Summary

Parser(java.io.BufferedReader br)
Constructs a Parser.

Method Summary

private boolean	getNextSym()
private Expression	parseArithExpression() Parses an ArithExpression
private Declaration	parseDeclaration() Parses a Declaration
private DeclarationList	parseDeclarationList() Parses a DeclarationList
private Expression	parseExpression() Parses an Expression
private ExpressionList	parseExpressionList() Parses an ExpressionList
private Expression	parseFactor() Parses a Factor
private NameList	parsenameList() Parses a nameList
Program	parseProgram() Parses the input and returns Program object corresponding to the input parsed.
private Expression	parseTerm() Parses a Term

Methods inherited from class java.lang.Object

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

Field Detail

NO_SYM

public static final int NO_SYM

LEFT_PAREN_SYM

public static final int LEFT_PAREN_SYM

RIGHT_PAREN_SYM

public static final int RIGHT_PAREN_SYM

NUMBER_SYM

public static final int NUMBER_SYM

NAME_SYM

public static final int NAME_SYM

EQUAL_SYM

public static final int EQUAL_SYM

SEMICOLON_SYM

public static final int SEMICOLON_SYM

IF_SYM

public static final int IF_SYM

THEN_SYM

public static final int THEN_SYM

ELSE_SYM

public static final int ELSE_SYM

WHERE_SYM

public static final int WHERE_SYM

PLUS_SYM

public static final int PLUS_SYM

MINUS_SYM

public static final int MINUS_SYM

MULT_SYM

public static final int MULT_SYM

DIV_SYM

public static final int DIV_SYM

LT_SYM

public static final int LT_SYM

GT_SYM

public static final int GT_SYM

EQEQ_SYM

public static final int EQEQ_SYM

NEQ_SYM

public static final int NEQ_SYM

LE_SYM

public static final int LE_SYM

GE_SYM

public static final int GE_SYM

COMMA_SYM

public static final int COMMA_SYM

currentSym

private int currentSym

currentNumber

private int currentNumber

currentName

private java.lang.String currentName

scanner

private Scanner scanner

Constructor Detail

Parser

public Parser(java.io.BufferedReader br)

Constructs a Parser.

Parameters:

br - BufferedReader to use as input stream

Method Detail

getNextSym

private boolean getNextSym()

parseProgram

public Program parseProgram()

Parses the input and returns Program object corresponding to the input parsed.

parseExpression

private Expression parseExpression()

Parses an Expression

parseArithExpression

private Expression parseArithExpression()

Parses an ArithExpression

parseTerm

private Expression parseTerm()

Parses a Term

parseFactor

private Expression parseFactor()

Parses a Factor

parseExpressionList

private ExpressionList parseExpressionList()

Parses an ExpressionList

parseDeclarationList

private DeclarationList parseDeclarationList()

Parses a DeclarationList

parseDeclaration

private Declaration parseDeclaration()

Parses a Declaration

parsenameList

private NameList parsenameList()

Parses a nameList