net.pwall.util

Class ComparableRef<T extends Comparable<? super T>>

java.lang.Object

net.pwall.util.Ref<T>

net.pwall.util.ComparableRef<T>

Type Parameters:

T - the class of the referred-to object

All Implemented Interfaces:

Serializable, Comparable<ComparableRef<T>>

public class ComparableRef<T extends Comparable<? super T>>
extends Ref<T>
implements Comparable<ComparableRef<T>>

A comparable reference to an object. The object must itself be Comparable.

Author:

Peter Wall

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
ComparableRef(T object) Construct a ComparableRef with the given value.

Method Summary

Modifier and Type	Method and Description
static <T extends Comparable<? super T>> int	compare(T a, T b) Compare two objects for order, allowing for nulls.
int	compareTo(ComparableRef<T> o) Compare this reference with another for order.

Methods inherited from class net.pwall.util.Ref

create, equal, equals, get, getObject, hashCode, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

ComparableRef

public ComparableRef(T object)

Construct a ComparableRef with the given value.

Parameters:

object - the value for the object

Method Detail

compareTo

public int compareTo(ComparableRef<T> o)

Compare this reference with another for order. The order is dependent on the order of the referred-to objects of each ComparableRef.

Specified by:

compareTo in interface Comparable<ComparableRef<T extends Comparable<? super T>>>

Parameters:

o - the other reference

Returns:

a negative value, zero, or a positive value, depending on whether this reference is less than, equal to, or greater than the other reference

See Also:

Comparable.compareTo(Object)

compare

public static <T extends Comparable<? super T>> int compare(T a,
                                                            T b)

Compare two objects for order, allowing for nulls. A null reference always compares lower than any non-null object, and two nulls are considered equal. This method is public and static so that it may be used as a comparison of two object references even when the ComparableRef class is not used.

Type Parameters:

T - class of the objects

Parameters:

a - the first object

b - the second object

Returns:

a negative value, zero, or a positive value, depending on whether the first object is less than, equal to, or greater than the second object