org.springframework.util.comparator

Class InstanceComparator<T>

java.lang.Object

org.springframework.util.comparator.InstanceComparator<T>

Type Parameters:

T - the type of objects that may be compared by this comparator

All Implemented Interfaces:

Comparator<T>

public class InstanceComparator<T>
extends Object
implements Comparator<T>

Compares objects based on an arbitrary class order. Allows objects to be sorted based on the types of class that they inherit — for example, this comparator can be used to sort a list of Numbers such that Longs occur before Integers.

Only the specified instanceOrder classes are considered during comparison. If two objects are both instances of the ordered type this comparator will return a value of 0. Consider combining with Comparator.thenComparing(Comparator) if additional sorting is required.

Since:

3.2

Author:

Phillip Webb

See Also:

Comparator.thenComparing(Comparator)

Constructor Summary

Constructors

Constructor and Description
InstanceComparator(Class<?>... instanceOrder) Create a new InstanceComparator instance.

Method Summary

Modifier and Type	Method and Description
int	compare(T o1, T o2)

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Comparator

comparing, comparing, comparingDouble, comparingInt, comparingLong, equals, naturalOrder, nullsFirst, nullsLast, reversed, reverseOrder, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

Constructor Detail

InstanceComparator

public InstanceComparator(Class<?>... instanceOrder)

Create a new InstanceComparator instance.

Parameters:

instanceOrder - the ordered list of classes that should be used when comparing objects. Classes earlier in the list will be given a higher priority.

Method Detail

compare

public int compare(T o1,
                   T o2)

Specified by:

compare in interface Comparator<T>