kotlin.collections.AbstractMutableCollection.kt Maven / Gradle / Ivy
/*
* Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
* Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
*/
package kotlin.collections
import java.util.AbstractCollection
/**
* Provides a skeletal implementation of the [MutableCollection] interface.
*
* @param E the type of elements contained in the collection. The collection is invariant in its element type.
*/
@SinceKotlin("1.1")
public actual abstract class AbstractMutableCollection protected actual constructor() : MutableCollection, AbstractCollection() {
/**
* Adds the specified element to the collection.
*
* This method is redeclared as abstract, because it's not implemented in the base class,
* so it must be always overridden in the concrete mutable collection implementation.
*
* @return `true` if the element has been added, `false` if the collection does not support duplicates
* and the element is already contained in the collection.
*/
actual abstract override fun add(element: E): Boolean
}