version 3.0

common/factory.h

@@ -0,0 +1,171 @@
+/*
+ * Copyright (c) 2010-2013 Juli Mallett. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef	COMMON_FACTORY_H
+#define	COMMON_FACTORY_H
+
+#include <map>
+#include <set>
+
+template<class C>
+class Factory {
+public:
+	Factory(void)
+	{ }
+
+	virtual ~Factory()
+	{ }
+
+	virtual C *create(void) const = 0;
+};
+
+template<class B, class C>
+class ConstructorFactory : public Factory<B> {
+public:
+	ConstructorFactory(void)
+	{ }
+
+	~ConstructorFactory()
+	{ }
+
+	B *create(void) const
+	{
+		return (new C());
+	}
+};
+
+template<class B, class C, typename A>
+class ConstructorArgFactory : public Factory<B> {
+	A a_;
+public:
+	ConstructorArgFactory(A a)
+	: a_(a)
+	{ }
+
+	~ConstructorArgFactory()
+	{ }
+
+	B *create(void) const
+	{
+		return (new C(a_));
+	}
+};
+
+template<class B, class C>
+class SubclassFactory : public Factory<B> {
+	Factory<C> *factory_;
+public:
+	SubclassFactory(Factory<C> *factory)
+	: factory_(factory)
+	{ }
+
+	~SubclassFactory()
+	{
+		delete factory_;
+		factory_ = NULL;
+	}
+
+	B *create(void) const
+	{
+		return (factory_->create());
+	}
+};
+
+template<class B, class C = B>
+struct factory {
+	Factory<B> *operator() (void) const
+	{
+		return (new ConstructorFactory<B, C>);
+	}
+
+	template<typename T>
+	Factory<B> *operator() (T arg) const
+	{
+		return (new ConstructorArgFactory<B, C, T>(arg));
+	}
+};
+
+template<typename K, typename C>
+class FactoryMap {
+	typedef std::map<K, Factory<C> *> map_type;
+
+	map_type map_;
+public:
+	FactoryMap(void)
+	: map_()
+	{ }
+
+	~FactoryMap()
+	{
+		typename map_type::iterator it;
+
+		while ((it = map_.begin()) != map_.end()) {
+			delete it->second;
+			map_.erase(it);
+		}
+	}
+
+	C *create(const K& key) const
+	{
+		typename map_type::const_iterator it;
+
+		it = map_.find(key);
+		if (it == map_.end())
+			return (NULL);
+		return (it->second->create());
+	}
+
+	void enter(const K& key, Factory<C> *factory)
+	{
+		typename map_type::iterator it;
+
+		it = map_.find(key);
+		if (it != map_.end()) {
+			delete it->second;
+			map_.erase(it);
+		}
+
+		map_[key] = factory;
+	}
+
+	template<typename S>
+	void enter(const K& key, Factory<S> *factory)
+	{
+		enter(key, new SubclassFactory<C, S>(factory));
+	}
+
+	std::set<K> keys(void) const
+	{
+		typename map_type::const_iterator it;
+		std::set<K> key_set;
+
+		for (it = map_.begin(); it != map_.end(); ++it)
+			key_set.insert(it->first);
+
+		return (key_set);
+	}
+};
+
+#endif /* !COMMON_FACTORY_H */