prolog.implementation
Class Value

java.lang.Object
  |
  +--prolog.implementation.Value

All Implemented Interfaces:

IAtom

public class Value

extends java.lang.Object

implements IAtom

This class encapsulates a constant value, one item of a relation. Because all names in the coder's program are replaced by integers, the internal representation of a atom is a integer value. This integer value can be decoded using the symboltable generated by the parser. A value can be compared with a filled cell in a database table row

prolog: myFact(dan,X).

in this example, a atom would be "dan" a value

Field Summary

protected int

value the interpreter internal representation of the constant. this is the index for the symboltable

Constructor Summary

Value(int value)
creates a new Value

Method Summary

boolean	equals(java.lang.Object o) overrides equals in java.lang.Object. if the given Object o is of the same class, the compare action is done, if not, it returns false
int	getName() the key in symboltable of the name
int	hashCode() returns a hashcode ;-) WOW ;-)
java.lang.String	toString() returns a string representation of the atom.
java.lang.String	toString(ISymbolTable table) returns a string representation of the atom. because all names of the programmer's programm are replaced by integers, this function requires the additional stringtable to decode the integers into strings again.

Methods inherited from class java.lang.Object

, clone, finalize, getClass, notify, notifyAll, registerNatives, wait, wait, wait

Field Detail

value

protected int value

the interpreter internal representation of the constant. this is the index for the symboltable

Constructor Detail

Value

public Value(int value)

creates a new Value

Parameters:

value - is the name used by the programer

Method Detail

equals

public boolean equals(java.lang.Object o)

overrides equals in java.lang.Object. if the given Object o is of the same class, the compare action is done, if not, it returns false

Overrides:

equals in class java.lang.Object

Returns:

true if the two values are the same in symboltable

getName

public int getName()

the key in symboltable of the name

Specified by:

getName in interface IAtom

toString

public java.lang.String toString(ISymbolTable table)

returns a string representation of the atom. because all names of the programmer's programm are replaced by integers, this function requires the additional stringtable to decode the integers into strings again.

Specified by:

toString in interface IAtom

toString

public java.lang.String toString()

returns a string representation of the atom.

Overrides:

toString in class java.lang.Object

hashCode

public int hashCode()

returns a hashcode ;-) WOW ;-)

Overrides:

hashCode in class java.lang.Object