gi
Class LR1_Grammar.Contexts

java.lang.Object
  gi.Lexicon.Stack
      gi.Lexicon.Set
          gi.LR0_Grammar.Contexts
              gi.LR1_Grammar.Contexts

Enclosing class:

LR1_Grammar

static class LR1_Grammar.Contexts

extends LR0_Grammar.Contexts

This class implements a set of LR(1) Contexts.

Version:

1.2

Author:

© 1999-2004 Craig A. Rich <carich@csupomona.edu>

Field Summary

(package private) Object[]	get The objects on this Stack.
(package private) int	size The number of objects on this Stack.

Constructor Summary

(package private)

LR1_Grammar.Contexts()

Method Summary

private int	add(Grammar.Production p, int lookahead, Lexicon.Set follow) Adds an LR(1) Context to this set of LR(1) Contexts.
(package private) boolean	add(Lexicon.Set S) Adds a Set of objects to this Set.
(package private) boolean	add(Lexicon.Set S, int start) Adds a Set of objects to this Set.
(package private) boolean	add(Object object) Adds an object to this Set.
(package private) boolean	contains(Object object) Indicates whether an object occurs in this Set.
(package private) Object	pop() Pops and returns the top object of this Stack.
private int	push(Grammar.Production p, int lookahead, Lexicon.Set follow) Pushes an LR(1) Context onto this set of LR(1) Contexts.
(package private) boolean	push(Object object) Pushes an object onto this Stack.
(package private) Object	top() Returns the top object of this Stack.
String	toString() Returns the string representation of this set of LR(0) Contexts.

Methods inherited from class java.lang.Object

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

Field Detail

get

Object[] get

The objects on this Stack.

size

int size

The number of objects on this Stack.

Constructor Detail

LR1_Grammar.Contexts

LR1_Grammar.Contexts()

Method Detail

add

private int add(Grammar.Production p,
                int lookahead,
                Lexicon.Set follow)

Adds an LR(1) Context to this set of LR(1) Contexts. The capacity is expanded if necessary.

Parameters:

p - the Production in the Context added.

lookahead - the lookahead position in the Context added.

follow - the follow Set in the Context added.

Returns:

the index in this set of LR(1) Contexts at which the Context occurs if this set of LR(1) Contexts changed; otherwise the size of this set of LR(1) Contexts.

push

private int push(Grammar.Production p,
                 int lookahead,
                 Lexicon.Set follow)

Pushes an LR(1) Context onto this set of LR(1) Contexts. The capacity is expanded by 100 if necessary.

Parameters:

p - the Production in the Context pushed.

lookahead - the lookahead position in the Context pushed.

follow - the follow Set in the Context pushed.

Returns:

the index in this set of LR(1) Contexts at which the pushed Context occurs.

toString

public String toString()

Returns the string representation of this set of LR(0) Contexts.

Overrides:

toString in class Lexicon.Stack

Returns:

the string representation of this set of LR(0) Contexts.

add

boolean add(Lexicon.Set S)

Adds a Set of objects to this Set. An object is not added if it occurs in this Set or it is null and the null exclusion indicator is true. The capacity is expanded if necessary.

Parameters:

S - the Set to add to this Set.

Returns:

true if this Set is changed; false otherwise.

add

boolean add(Lexicon.Set S,
            int start)

Adds a Set of objects to this Set. An object is not added if it occurs in this Set or it is null and the null exclusion indicator is true. The capacity is expanded if necessary.

Parameters:

S - the Set to add to this Set.

start - the index in S beyond which objects are added.

Returns:

true if this Set is changed; false otherwise.

add

boolean add(Object object)

Adds an object to this Set. The object is not added if it occurs in this Set or it is null and the null exclusion indicator is true. The capacity is expanded if necessary.

Parameters:

object - the object to add to this Set.

Returns:

true if this Set is changed; false otherwise.

contains

boolean contains(Object object)

Indicates whether an object occurs in this Set.

Parameters:

object - the object whose membership if requested.

Returns:

true if o occurs in this Set; false otherwise.

pop

Object pop()

Pops and returns the top object of this Stack.

Returns:

the top object of this Stack.

push

boolean push(Object object)

Pushes an object onto this Stack. The capacity is expanded by 50% if necessary.

Parameters:

object - the object to push onto this Stack.

Returns:

true indicates this Stack is changed.

top

Object top()

Returns the top object of this Stack.

Returns:

the top object of this Stack.