Package org.zkoss.util

## Class IdentityComparator<T>

- java.lang.Object
- - org.zkoss.util.IdentityComparator<T>

- All Implemented Interfaces:
    `java.util.Comparator<T>`

      public class IdentityComparator<T>
      extends java.lang.Object
      implements java.util.Comparator<T>

  The comparator uses == and System.identifyHashCode to compare two objects. It assumes if o1 != o2, then c1 != c2 where c1 = System.identityHashCode(o1).

  This is useful if dynamic proxy is used with TreeSet or TreeMap (so equals is expensive). Reason: the speed of identifyHashCode is much faster than dynamic proxy (150:1).

  However, if possible, java.util.IdentityHashMap and `IdentityHashSet` are preferred.

  Author:
    tomyeh
  See Also:
    `IdentityHashSet`

- - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `IdentityComparator()` |

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method | 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

      `equals, reversed, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong`

- - ### Constructor Detail

    - #### IdentityComparator

          public IdentityComparator()

  - ### Method Detail

    - #### compare

          public int compare​(T o1,
                             T o2)

      Specified by:
        `compare` in interface `java.util.Comparator<T>`