michael@0: // Copyright 2005, Google Inc.
michael@0: // All rights reserved.
michael@0: //
michael@0: // Redistribution and use in source and binary forms, with or without
michael@0: // modification, are permitted provided that the following conditions are
michael@0: // met:
michael@0: //
michael@0: //     * Redistributions of source code must retain the above copyright
michael@0: // notice, this list of conditions and the following disclaimer.
michael@0: //     * Redistributions in binary form must reproduce the above
michael@0: // copyright notice, this list of conditions and the following disclaimer
michael@0: // in the documentation and/or other materials provided with the
michael@0: // distribution.
michael@0: //     * Neither the name of Google Inc. nor the names of its
michael@0: // contributors may be used to endorse or promote products derived from
michael@0: // this software without specific prior written permission.
michael@0: //
michael@0: // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
michael@0: // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
michael@0: // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
michael@0: // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
michael@0: // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
michael@0: // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
michael@0: // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
michael@0: // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
michael@0: // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
michael@0: // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
michael@0: // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
michael@0: 
michael@0: // A sample program demonstrating using Google C++ testing framework.
michael@0: //
michael@0: // Author: wan@google.com (Zhanyong Wan)
michael@0: 
michael@0: #ifndef GTEST_SAMPLES_SAMPLE3_INL_H_
michael@0: #define GTEST_SAMPLES_SAMPLE3_INL_H_
michael@0: 
michael@0: #include <stddef.h>
michael@0: 
michael@0: 
michael@0: // Queue is a simple queue implemented as a singled-linked list.
michael@0: //
michael@0: // The element type must support copy constructor.
michael@0: template <typename E>  // E is the element type
michael@0: class Queue;
michael@0: 
michael@0: // QueueNode is a node in a Queue, which consists of an element of
michael@0: // type E and a pointer to the next node.
michael@0: template <typename E>  // E is the element type
michael@0: class QueueNode {
michael@0:   friend class Queue<E>;
michael@0: 
michael@0:  public:
michael@0:   // Gets the element in this node.
michael@0:   const E& element() const { return element_; }
michael@0: 
michael@0:   // Gets the next node in the queue.
michael@0:   QueueNode* next() { return next_; }
michael@0:   const QueueNode* next() const { return next_; }
michael@0: 
michael@0:  private:
michael@0:   // Creates a node with a given element value.  The next pointer is
michael@0:   // set to NULL.
michael@0:   explicit QueueNode(const E& an_element) : element_(an_element), next_(NULL) {}
michael@0: 
michael@0:   // We disable the default assignment operator and copy c'tor.
michael@0:   const QueueNode& operator = (const QueueNode&);
michael@0:   QueueNode(const QueueNode&);
michael@0: 
michael@0:   E element_;
michael@0:   QueueNode* next_;
michael@0: };
michael@0: 
michael@0: template <typename E>  // E is the element type.
michael@0: class Queue {
michael@0:  public:
michael@0:   // Creates an empty queue.
michael@0:   Queue() : head_(NULL), last_(NULL), size_(0) {}
michael@0: 
michael@0:   // D'tor.  Clears the queue.
michael@0:   ~Queue() { Clear(); }
michael@0: 
michael@0:   // Clears the queue.
michael@0:   void Clear() {
michael@0:     if (size_ > 0) {
michael@0:       // 1. Deletes every node.
michael@0:       QueueNode<E>* node = head_;
michael@0:       QueueNode<E>* next = node->next();
michael@0:       for (; ;) {
michael@0:         delete node;
michael@0:         node = next;
michael@0:         if (node == NULL) break;
michael@0:         next = node->next();
michael@0:       }
michael@0: 
michael@0:       // 2. Resets the member variables.
michael@0:       head_ = last_ = NULL;
michael@0:       size_ = 0;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   // Gets the number of elements.
michael@0:   size_t Size() const { return size_; }
michael@0: 
michael@0:   // Gets the first element of the queue, or NULL if the queue is empty.
michael@0:   QueueNode<E>* Head() { return head_; }
michael@0:   const QueueNode<E>* Head() const { return head_; }
michael@0: 
michael@0:   // Gets the last element of the queue, or NULL if the queue is empty.
michael@0:   QueueNode<E>* Last() { return last_; }
michael@0:   const QueueNode<E>* Last() const { return last_; }
michael@0: 
michael@0:   // Adds an element to the end of the queue.  A copy of the element is
michael@0:   // created using the copy constructor, and then stored in the queue.
michael@0:   // Changes made to the element in the queue doesn't affect the source
michael@0:   // object, and vice versa.
michael@0:   void Enqueue(const E& element) {
michael@0:     QueueNode<E>* new_node = new QueueNode<E>(element);
michael@0: 
michael@0:     if (size_ == 0) {
michael@0:       head_ = last_ = new_node;
michael@0:       size_ = 1;
michael@0:     } else {
michael@0:       last_->next_ = new_node;
michael@0:       last_ = new_node;
michael@0:       size_++;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   // Removes the head of the queue and returns it.  Returns NULL if
michael@0:   // the queue is empty.
michael@0:   E* Dequeue() {
michael@0:     if (size_ == 0) {
michael@0:       return NULL;
michael@0:     }
michael@0: 
michael@0:     const QueueNode<E>* const old_head = head_;
michael@0:     head_ = head_->next_;
michael@0:     size_--;
michael@0:     if (size_ == 0) {
michael@0:       last_ = NULL;
michael@0:     }
michael@0: 
michael@0:     E* element = new E(old_head->element());
michael@0:     delete old_head;
michael@0: 
michael@0:     return element;
michael@0:   }
michael@0: 
michael@0:   // Applies a function/functor on each element of the queue, and
michael@0:   // returns the result in a new queue.  The original queue is not
michael@0:   // affected.
michael@0:   template <typename F>
michael@0:   Queue* Map(F function) const {
michael@0:     Queue* new_queue = new Queue();
michael@0:     for (const QueueNode<E>* node = head_; node != NULL; node = node->next_) {
michael@0:       new_queue->Enqueue(function(node->element()));
michael@0:     }
michael@0: 
michael@0:     return new_queue;
michael@0:   }
michael@0: 
michael@0:  private:
michael@0:   QueueNode<E>* head_;  // The first node of the queue.
michael@0:   QueueNode<E>* last_;  // The last node of the queue.
michael@0:   size_t size_;  // The number of elements in the queue.
michael@0: 
michael@0:   // We disallow copying a queue.
michael@0:   Queue(const Queue&);
michael@0:   const Queue& operator = (const Queue&);
michael@0: };
michael@0: 
michael@0: #endif  // GTEST_SAMPLES_SAMPLE3_INL_H_