org.linqs.psl.model.predicate

Class Predicate

java.lang.Object

org.linqs.psl.model.predicate.Predicate

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

FunctionalPredicate, StandardPredicate

public abstract class Predicate
extends Object
implements Serializable

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.

See Also:

Serialized Form

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.
void	close() Close the predicate and free related resrouces.
boolean	equals(Object oth)
static Predicate	get(String name)
static Collection<Predicate>	getAll()
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.
int	hashCode()
static void	registerPredicate(Predicate predicate)
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, 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.

close

public void close()

Close the predicate and free related resrouces. It will be very rare to call this method. Most predicates stay alive for the duration of PSL's run.

toString

public String toString()

Overrides:

toString in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object oth)

Overrides:

equals in class Object

registerPredicate

public static void registerPredicate(Predicate predicate)

get

public static Predicate get(String name)

getAll

public static Collection<Predicate> getAll()

clearForTesting

public static void clearForTesting()

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