org.onosproject.store.service.TransactionalSet Maven / Gradle / Ivy
/*
* Copyright 2015-present Open Networking Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* hcodep://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.onosproject.store.service;
/**
* Transactional Set data structure.
*
* A TransactionalSet is implemented with the help of TransactionalMap data structure.
* All operations performed on this set within a transaction boundary are invisible externally
* until the point when the transaction commits. A commit usually succeeds in the absence of conflicts.
*
* @param type of element.
*/
public interface TransactionalSet {
/**
* Adds the specified element to this set if it is not already present
* (optional operation). More formally, adds the specified element
* e to this set if the set contains no element e2
* such that
* (e==null ? e2==null : e.equals(e2)).
* If this set already contains the element, the call leaves the set
* unchanged and returns false. In combination with the
* restriction on constructors, this ensures that sets never contain
* duplicate elements.
*
* @param e element to be added to this set
* @return true if this set did not already contain the specified
* element
*/
boolean add(E e);
/**
* Removes the specified element from this set if it is present
* (optional operation). More formally, removes an element e
* such that
* (o==null ? e==null : o.equals(e)), if
* this set contains such an element. Returns true if this set
* contained the element (or equivalently, if this set changed as a
* result of the call). (This set will not contain the element once the
* call returns.)
*
* @param e element to be removed to this set
* @return true if this set contained the specified element
*/
boolean remove(E e);
/**
* Returns true if this set contains the specified element.
* More formally, returns true if and only if this set
* contains an element e such that
* (o==null ? e==null : o.equals(e)).
*
* @param e element whose presence in this set is to be tested
* @return true if this set contains the specified element
* @throws ClassCastException if the type of the specified element
* is incompatible with this set
* @throws NullPointerException if the specified element is null and this
* set does not permit null elements
*/
boolean contains(E e);
}