org.openzen.zengarden.lexer

Class NFA<T extends java.lang.Comparable<T>>

java.lang.Object

org.openzen.zengarden.lexer.NFA<T>

Type Parameters:

T - final state type (for a TokenStream, a TokenType)

public class NFA<T extends java.lang.Comparable<T>>
extends java.lang.Object

Represents an NFA. NFAs can be compiled from a list of regular expressions.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	NFA.NFAState<T> Represents an NFA state.

Field Summary

Fields

Modifier and Type	Field and Description
static int	EPSILON
static int	NOFINAL

Constructor Summary

Constructors

Constructor and Description
NFA(java.lang.Class<T> tokenClass, NFA.NFAState<T> initial) Creates a new NFA with the specified initial state.
NFA(java.lang.String[] regexp, T[] finals) Converts an array of regular expressions to an NFA.
NFA(java.lang.String regexp, T state) Creates a new NFA from the specified regular expression.
NFA(ZList<java.lang.String> regexp, ZList<T> finals) Converts a list of regular expressions to an NFA.

Method Summary

Modifier and Type	Method and Description
CompiledDFA<T>	compile() Converts the NFA to a DFA and optimizes and compiles it into an efficient format.
DFA<T>	toDFA() Converts this NFA to a DFA.

Methods inherited from class java.lang.Object

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

Field Detail

NOFINAL

public static final int NOFINAL

See Also:

Constant Field Values

EPSILON

public static final int EPSILON

See Also:

Constant Field Values

Constructor Detail

NFA

public NFA(java.lang.Class<T> tokenClass,
           NFA.NFAState<T> initial)

Creates a new NFA with the specified initial state.

Parameters:

tokenClass - token class

initial - initial state

NFA

public NFA(java.lang.String regexp,
           T state)

Creates a new NFA from the specified regular expression. Note: the regular expression implementation is not complete. Shorthand character classes (\s, \w, \d), hexadecimal and unicode escape sequences and unicode properties are not implemented. Anchors, lazy plus operators, lookbehind and lookforward are not implemented since they cannot be implemented in an NFA.

Parameters:

regexp - regular expression

state - resulting state

NFA

public NFA(java.lang.String[] regexp,
           T[] finals)

Converts an array of regular expressions to an NFA. Each regular expression can have its own final class. The length of both arrays must match.

Parameters:

regexp - regular expression array

finals - final classes

NFA

public NFA(ZList<java.lang.String> regexp,
           ZList<T> finals)

Converts a list of regular expressions to an NFA. Each regular expression can have its own final class. The length of both arrays must match.

Parameters:

regexp - regular expression array

finals - final classes

Method Detail

toDFA

public DFA<T> toDFA()

Converts this NFA to a DFA. The resulting DFA is not optimal. If the NFA is ambiguous, the token with lowest value will receive preference.

Returns:

this NFA as DFA

compile

public CompiledDFA<T> compile()

Converts the NFA to a DFA and optimizes and compiles it into an efficient format.

Returns:

compiled DFA