Variable

java.lang.Object
- jpl.Term
- - jpl.Variable

```
public class Variable
extends Term
```
This class supports Java representations of Prolog variables.
A jpl.Variable instance is equivalent to a variable in a fragment of Prolog source text: it is *not* a "live" variable within a Prolog stack or heap. A corresponding Prolog variable is created only upon opening a Query whose goal refers to a Variable (and then only temporarily).
Copyright (C) 2004 Paul Singleton
Copyright (C) 1998 Fred Dushin
This library is free software; you can redistribute it and/or modify it under the terms of the GNU Library Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library Public License for more details.

Field Summary

Fields
Modifier and Type Field and Description

java.lang.String name

Fields
Modifier and Type	Field and Description
`java.lang.String`	`name`

Constructor Summary

Constructors
Constructor and Description
`Variable()` Create a new Variable with new sequential name of the form "_261".
`Variable(java.lang.String name)` Create a new Variable with 'name' (which must not be null or ""), and may one day be constrained to comply with traditional Prolog syntax.

Method Summary

All Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type	Method and Description
`Term`	`arg(int i)` throws a JPLException (arg(int) is defined only for Compound and Atom)
`Term[]`	`args()` The (nonexistent) args of this Variable
`java.lang.String`	`debugString()` Deprecated.
`boolean`	`equals(java.lang.Object obj)` A Variable is equal to another if their names are the same and they are not anonymous.
`boolean`	`hasFunctor(double value, int arity)` Tests whether this Term's functor has (double) 'name' and 'arity' Returns false if called inappropriately
`boolean`	`hasFunctor(int value, int arity)` Tests whether this Term's functor has (int) 'name' and 'arity' Returns false if called inappropriately
`boolean`	`hasFunctor(java.lang.String name, int arity)` Tests whether this Term's functor has (String) 'name' and 'arity' Returns false if called inappropriately
`java.lang.Object`	`jrefToObject()`
`java.lang.String`	`name()` returns the lexical name of this Variable
`java.lang.String`	`toString()` Returns a Prolog source text representation of this Variable
`int`	`type()` returns the type of this subclass of Term, i.e.
`java.lang.String`	`typeName()` returns the typeName of this subclass of Term, i.e.

Methods inherited from class jpl.Term
arity, debugString, doubleValue, floatValue, intValue, isAtom, isCompound, isFloat, isInteger, isJFalse, isJNull, isJObject, isJRef, isJTrue, isJVoid, isVariable, listLength, longValue, objectToJRef, put, putParams, putParams, putTerm, toString, toTermArray

Methods inherited from class java.lang.Object
getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - name
```
public final java.lang.String name
```
- Constructor Detail
  - Variable
```
public Variable(java.lang.String name)
```
    Create a new Variable with 'name' (which must not be null or ""), and may one day be constrained to comply with traditional Prolog syntax.
    
    Parameters:
    
    name - the source name of this Variable
  - Variable
```
public Variable()
```
    Create a new Variable with new sequential name of the form "_261".
- Method Detail
  - args
```
public Term[] args()
```
    The (nonexistent) args of this Variable
    
    Specified by:
    
    args in class Term
    
    Returns:
    
    the (nonexistent) args of this Variable (never)
    
    Throws:
    
    JPLException
  - hasFunctor
```
public boolean hasFunctor(java.lang.String name,
                          int arity)
```
    Description copied from class: Term
    
    Tests whether this Term's functor has (String) 'name' and 'arity' Returns false if called inappropriately
    
    Specified by:
    
    hasFunctor in class Term
    
    Returns:
    
    whether this Term's functor has (String) 'name' and 'arity'
  - hasFunctor
```
public boolean hasFunctor(int value,
                          int arity)
```
    Description copied from class: Term
    
    Tests whether this Term's functor has (int) 'name' and 'arity' Returns false if called inappropriately
    
    Specified by:
    
    hasFunctor in class Term
    
    Returns:
    
    whether this Term's functor has (int) 'name' and 'arity'
  - hasFunctor
```
public boolean hasFunctor(double value,
                          int arity)
```
    Description copied from class: Term
    
    Tests whether this Term's functor has (double) 'name' and 'arity' Returns false if called inappropriately
    
    Specified by:
    
    hasFunctor in class Term
    
    Returns:
    
    whether this Term's functor has (double) 'name' and 'arity'
  - jrefToObject
```
public java.lang.Object jrefToObject()
```
    Specified by:
    
    jrefToObject in class Term
  - name
```
public final java.lang.String name()
```
    returns the lexical name of this Variable
    
    Overrides:
    
    name in class Term
    
    Returns:
    
    the lexical name of this Variable
  - type
```
public final int type()
```
    returns the type of this subclass of Term, i.e. Prolog.VARIABLE
    
    Specified by:
    
    type in class Term
    
    Returns:
    
    the type of this subclass of Term, i.e. Prolog.VARIABLE
  - typeName
```
public java.lang.String typeName()
```
    returns the typeName of this subclass of Term, i.e. "Variable"
    
    Specified by:
    
    typeName in class Term
    
    Returns:
    
    the typeName of this subclass of Term, i.e. "Variable"
  - toString
```
public java.lang.String toString()
```
    Returns a Prolog source text representation of this Variable
    
    Overrides:
    
    toString in class java.lang.Object
    
    Returns:
    
    a Prolog source text representation of this Variable
  - equals
```
public final boolean equals(java.lang.Object obj)
```
    A Variable is equal to another if their names are the same and they are not anonymous.
    
    Overrides:
    
    equals in class java.lang.Object
    
    Parameters:
    
    obj - The Object to compare.
    
    Returns:
    
    true if the Object is a Variable and the above condition apply.
  - arg
```
public final Term arg(int i)
```
    throws a JPLException (arg(int) is defined only for Compound and Atom)
    
    Specified by:
    
    arg in class Term
    
    Returns:
    
    the ith argument (counting from 1) of this Variable (never)
  - debugString
```
public java.lang.String debugString()
```
    Deprecated.
    
    Returns a debug-friendly String representation of an Atom.
    
    Specified by:
    
    debugString in class Term
    
    Returns:
    
    a debug-friendly String representation of an Atom

Class Variable

Field Summary

Constructor Summary

Method Summary

Methods inherited from class jpl.Term

Methods inherited from class java.lang.Object

Field Detail

name

Constructor Detail

Variable

Variable

Method Detail

args

hasFunctor

hasFunctor

hasFunctor

jrefToObject

name

type

typeName

toString

equals

arg

debugString