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Object.GetHashCode Method

Definition

Returns a hash code value for the object.

[Android.Runtime.Register("hashCode", "()I", "GetGetHashCodeHandler")]
public override int GetHashCode ();
[<Android.Runtime.Register("hashCode", "()I", "GetGetHashCodeHandler")>]
override this.GetHashCode : unit -> int

Returns

a hash code value for this object.

Attributes

Remarks

Returns a hash code value for the object. This method is supported for the benefit of hash tables such as those provided by java.util.HashMap.

The general contract of hashCode is: <ul> <li>Whenever it is invoked on the same object more than once during an execution of a Java application, the hashCode method must consistently return the same integer, provided no information used in equals comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application. <li>If two objects are equal according to the equals(Object) method, then calling the hashCode method on each of the two objects must produce the same integer result. <li>It is <em>not</em> required that if two objects are unequal according to the java.lang.Object#equals(java.lang.Object) method, then calling the hashCode method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables. </ul>

As much as is reasonably practical, the hashCode method defined by class Object does return distinct integers for distinct objects. (The hashCode may or may not be implemented as some function of an object's memory address at some point in time.)

Java documentation for java.lang.Object.hashCode().

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

See also