planet.symphony
Interface Comparer
- All Known Implementing Classes:
- IdComparer
public interface Comparer
Comparer interface imposes a total ordering on some collection of objects. The data structure calls
compare method and gets the order of the elements on the collection. The ordering imposed by
Comparer c must be consistent and implies an specific definition of a comparer for each object's type.
- Author:
- Marc Sanchez (marc.sanchez@estudiants.urv.es)
Method Summary |
int |
compare(java.lang.Object o1,
java.lang.Object o2)
A comparison function, which imposes a total ordering on some collection of objects. |
compare
int compare(java.lang.Object o1,
java.lang.Object o2)
- A comparison function, which imposes a total ordering on some collection of objects. Comparer
can be passed to a sort method to allow precise control over the sort order. Comparer can also
be used to control the order of certain data structures. The ordering imposed by a Comparer c
on a set of elements S is said to be consistent with equals if and only if (compare((Object)e1,
(Object)e2)==0) has the same boolean value as e1.equals((Object)e2) for every e1 and e2 in S.
- Parameters:
o1
- The first object to be compared.o2
- The second object to be compared.
- Returns:
- A negative integer, zero, or a positive integer as the first argument is less than,
equal to, or greater than the second.
- Throws:
java.lang.ClassCastException
- - if the arguments' types prevent them from being compared by this
Comparer.