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ICollection.Equals(Object) Method

Definition

Compares the specified object with this collection for equality.

[Android.Runtime.Register("equals", "(Ljava/lang/Object;)Z", "GetEquals_Ljava_lang_Object_Handler:Java.Util.ICollectionInvoker, Mono.Android, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null")]
public bool Equals (Java.Lang.Object? o);
[<Android.Runtime.Register("equals", "(Ljava/lang/Object;)Z", "GetEquals_Ljava_lang_Object_Handler:Java.Util.ICollectionInvoker, Mono.Android, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null")>]
abstract member Equals : Java.Lang.Object -> bool

Parameters

o
Object

object to be compared for equality with this collection

Returns

true if the specified object is equal to this collection

Attributes

Remarks

Compares the specified object with this collection for equality.

While the Collection interface adds no stipulations to the general contract for the Object.equals, programmers who implement the Collection interface "directly" (in other words, create a class that is a Collection but is not a Set or a List) must exercise care if they choose to override the Object.equals. It is not necessary to do so, and the simplest course of action is to rely on Object's implementation, but the implementor may wish to implement a "value comparison" in place of the default "reference comparison." (The List and Set interfaces mandate such value comparisons.)

The general contract for the Object.equals method states that equals must be symmetric (in other words, a.equals(b) if and only if b.equals(a)). The contracts for List.equals and Set.equals state that lists are only equal to other lists, and sets to other sets. Thus, a custom equals method for a collection class that implements neither the List nor Set interface must return false when this collection is compared to any list or set. (By the same logic, it is not possible to write a class that correctly implements both the Set and List interfaces.)

Java documentation for java.util.Collection.equals(java.lang.Object).

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

Applies to