lp.struct
Class LpAbstractStructureUnit

java.lang.Object
  lp.struct.LpAbstractStructureUnit

All Implemented Interfaces:

LpStructureUnit

Direct Known Subclasses:

LpAtom, LpCompoundTerm, LpConstant, LpFunction, LpLiteral, LpPredicate, LpRule, LpVariable

public abstract class LpAbstractStructureUnit
extends Object
implements LpStructureUnit

This abstract class offers a default implementation of the toString() method for all classes implementing the LpStructureUnit interface.

Version:

1.0.0

Author:

Martin Slota

See Also:

LpStructureUnit, LpConstant, LpVariable, LpCompoundTerm, LpFunction, LpPredicate, LpAtom, LpLiteral, LpRule

Field Summary

protected static LpBuffer

TO_STRING_BUFFER A single LpBuffer instance for the toString() method.

Constructor Summary

LpAbstractStructureUnit()

Method Summary

String	toString()
protected static <T> List<T>	toUnmodifiableList(List<T> list) Converts the given list to an unmodifiable list using the Collections.unmodifiableList(List) method.
protected static <T> Set<T>	toUnmodifiableSet(Set<T> set) Converts the given set to an unmodifiable set using the Collections.unmodifiableSet(Set) method.

Methods inherited from class java.lang.Object

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

Methods inherited from interface lp.struct.LpStructureUnit

accept

Field Detail

TO_STRING_BUFFER

protected static final LpBuffer TO_STRING_BUFFER

A single LpBuffer instance for the toString() method. All calls to toString() are synchronized on it, so it is not a good idea to call toString() on LpStructureUnits from many threads...

Constructor Detail

LpAbstractStructureUnit

public LpAbstractStructureUnit()

Method Detail

toString

public String toString()

Overrides:

toString in class Object

toUnmodifiableList

protected static <T> List<T> toUnmodifiableList(List<T> list)

Converts the given list to an unmodifiable list using the Collections.unmodifiableList(List) method. But there are two differences:

• on null input an empty list is returned (see Collections.emptyList())
• if the list throws an UnsupportedOperationException when we call its List.addAll(Collection) method, it is not wrapped in another protecting object. This prevents stacking of UnmodifiableList instances.

Parameters:

list - the list whose read-only view should be returned

Returns:

as specified above

toUnmodifiableSet

protected static <T> Set<T> toUnmodifiableSet(Set<T> set)

Converts the given set to an unmodifiable set using the Collections.unmodifiableSet(Set) method. But there are two differences:

• on null input an empty set is returned (see Collections.emptySet())
• if the set throws an UnsupportedOperationException when we call its Set.addAll(Collection) method, it is not wrapped in another protecting object. This prevents stacking of UnmodifiableSet instances.

Parameters:

set - the set whose read-only view should be returned

Returns:

as specified above