org.linqs.psl.model.predicate

Class Predicate

java.lang.Object

org.linqs.psl.model.predicate.Predicate

Direct Known Subclasses:

FunctionalPredicate, StandardPredicate

public abstract class Predicate
extends Object

A relation that can be applied to Terms to form Atoms. A Predicate is uniquely identified by its name (and all predicate names are converted to upper case). Predicates cannot be constructed directly. Instead, they are constructed via the appropriate gegetthod in each subclass.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Predicate(String name, ConstantType[] types)
protected	Predicate(String name, ConstantType[] types, boolean checkName)

Method Summary

Modifier and Type	Method and Description
static void	clearForTesting() Clear out all active predicates.
static Predicate	get(String name)
ConstantType	getArgumentType(int position) Returns the ArgumentType which a Term must have to be a valid argument for a particular argument position of this Predicate.
int	getArity() Returns the number of Terms that are related when using this Predicate.
String	getName() Returns the name of this Predicate.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

Predicate

protected Predicate(String name,
                    ConstantType[] types)

Predicate

protected Predicate(String name,
                    ConstantType[] types,
                    boolean checkName)

Method Detail

getName

public String getName()

Returns the name of this Predicate.

Returns:

a string identifier for this Predicate

getArity

public int getArity()

Returns the number of Terms that are related when using this Predicate. In other words, the arity of a Predicate is the number of arguments it accepts. For example, the Predicate Related(A, B) has an arity of 2.

getArgumentType

public ConstantType getArgumentType(int position)

Returns the ArgumentType which a Term must have to be a valid argument for a particular argument position of this Predicate.

toString

public String toString()

Overrides:

toString in class Object

get

public static Predicate get(String name)

clearForTesting

public static void clearForTesting()

Clear out all active predicates. This should ONLY be used in testing to set up for subsequent tests.