| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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 |
| * |
| * http://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. |
| */ |
| |
| #ifndef _DECAF_UTIL_CONCURRENT_COPYONWRITEARRAYSET_H_ |
| #define _DECAF_UTIL_CONCURRENT_COPYONWRITEARRAYSET_H_ |
| |
| #include <decaf/util/NoSuchElementException.h> |
| #include <decaf/lang/exceptions/IndexOutOfBoundsException.h> |
| #include <decaf/lang/ArrayPointer.h> |
| #include <decaf/lang/Pointer.h> |
| #include <decaf/util/concurrent/CopyOnWriteArrayList.h> |
| #include <decaf/util/concurrent/Synchronizable.h> |
| #include <decaf/util/Set.h> |
| #include <decaf/util/Arrays.h> |
| #include <decaf/util/AbstractSet.h> |
| |
| namespace decaf { |
| namespace util { |
| namespace concurrent { |
| |
| /** |
| * Since the CopyOnWriteArraySet and the CopyOnWriteArrayList share much of the same |
| * operational semantics this class uses the CopyOnWriteArrayList for all its underlying |
| * operations. |
| * |
| * This collection is best used in applications where the Set size is usually small and |
| * write operations are minimal as they result in a copy of the underlying array being |
| * created. Reads are generally fast and the iterators provided by this collection |
| * do not block as they operate on a snapshot of the data taken at the time of their |
| * creation. |
| * |
| * @since 1.0 |
| */ |
| template< typename E > |
| class CopyOnWriteArraySet : public AbstractSet<E> { |
| private: |
| |
| CopyOnWriteArrayList<E> array; |
| |
| public: |
| |
| CopyOnWriteArraySet() : AbstractSet<E> (), array() { |
| } |
| |
| CopyOnWriteArraySet(const Collection<E>& collection) : AbstractSet<E> (), array() { |
| this->copy(collection); |
| } |
| |
| CopyOnWriteArraySet(const E* array, int size) : AbstractSet<E> (), array() { |
| for (int i = 0; i < size; ++i) { |
| this->array.addIfAbsent(array[i]); |
| } |
| } |
| |
| virtual ~CopyOnWriteArraySet() { |
| } |
| |
| public: |
| |
| virtual void copy(const Collection<E>& collection) { |
| this->array.copy(collection); |
| } |
| |
| virtual decaf::util::Iterator<E>* iterator() { |
| return this->array.iterator(); |
| } |
| |
| virtual decaf::util::Iterator<E>* iterator() const { |
| return this->array.iterator(); |
| } |
| |
| virtual int size() const { |
| return this->array.size(); |
| } |
| |
| virtual bool isEmpty() const { |
| return this->array.isEmpty(); |
| } |
| |
| virtual bool add(const E& value) { |
| return this->array.addIfAbsent(value); |
| } |
| |
| virtual bool addAll(const Collection<E>& collection) { |
| return this->array.addAllAbsent(collection) > 0 ? true : false; |
| } |
| |
| virtual void clear() { |
| this->array.clear(); |
| } |
| |
| virtual bool contains(const E& value) const { |
| return this->array.contains(value); |
| } |
| |
| virtual bool containsAll(const Collection<E>& collection) const { |
| return this->array.containsAll(collection); |
| } |
| |
| virtual bool remove(const E& value) { |
| return this->array.remove(value); |
| } |
| |
| virtual bool removeAll(const Collection<E>& collection) { |
| return this->array.removeAll(collection); |
| } |
| |
| virtual bool retainAll(const Collection<E>& collection) { |
| return this->array.retainAll(collection); |
| } |
| |
| virtual std::vector<E> toArray() const { |
| return this->array.toArray(); |
| } |
| |
| virtual bool equals(const Collection<E>& collection) const { |
| |
| if ((void*) this == &collection) { |
| return true; |
| } |
| |
| const Set<E>* asSet = dynamic_cast<const Set<E>*> (&collection); |
| if (asSet == NULL) { |
| return false; |
| } |
| |
| if (this->size() != asSet->size()) { |
| return false; |
| } |
| |
| std::auto_ptr<Iterator<E> > setIter(asSet->iterator()); |
| |
| // Use a single snapshot of underlying array |
| CopyOnWriteArrayList<E> array(this->array); |
| int length = array.size(); |
| decaf::lang::ArrayPointer<bool> matched(length, false); |
| |
| while (setIter->hasNext()) { |
| E value = setIter->next(); |
| int matchedAt = array.indexOf(value); |
| if (matchedAt >= 0) { |
| matched[matchedAt] = true; |
| } |
| } |
| |
| for (int i = 0; i < length; ++i) { |
| if (matched[i] == false) { |
| return false; |
| } |
| } |
| |
| return true; |
| } |
| |
| }; |
| |
| }}} |
| |
| #endif /* _DECAF_UTIL_CONCURRENT_COPYONWRITEARRAYSET_H_ */ |