| /* |
| * Copyright 1999-2004 The Apache Software 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 |
| * |
| * 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. |
| */ |
| #if !defined(XPATHFACTORY_HEADER_GUARD_1357924680) |
| #define XPATHFACTORY_HEADER_GUARD_1357924680 |
| |
| |
| |
| // Base include file. Must be first. |
| #include <xalanc/XPath/XPathDefinitions.hpp> |
| |
| |
| |
| #include <cassert> |
| #include <functional> |
| |
| |
| |
| XALAN_CPP_NAMESPACE_BEGIN |
| |
| |
| |
| class XPath; |
| |
| |
| |
| class XALAN_XPATH_EXPORT XPathFactory |
| { |
| public: |
| |
| explicit |
| XPathFactory(); |
| |
| virtual |
| ~XPathFactory(); |
| |
| /** |
| * Return an XPath to the factory. |
| * |
| * @param theXPath The XPath to be returned |
| * @return true if the object belongs to the factory, false if not. |
| */ |
| bool |
| returnObject(const XPath* theXPath) |
| { |
| return doReturnObject(theXPath); |
| } |
| |
| /** |
| * Reset the instance. This invalidates all existing instances created |
| * with this XPathFactory. |
| */ |
| virtual void |
| reset() = 0; |
| |
| /** |
| * Create an XPath. The XPath instance is owned by the factory, and should |
| * not be deleted. The factory will manage the lifetime. |
| * |
| */ |
| virtual XPath* |
| create() = 0; |
| |
| /** |
| * |
| * A functor for use with stl algorithms. |
| * |
| */ |
| #if defined(XALAN_NO_STD_NAMESPACE) |
| struct DeleteXPathFunctor : public unary_function<const XPath*, void> |
| #else |
| struct DeleteXPathFunctor : public std::unary_function<const XPath*, void> |
| #endif |
| { |
| public: |
| |
| DeleteXPathFunctor( |
| XPathFactory& theFactoryInstance, |
| bool fInReset = false) : |
| m_factoryInstance(theFactoryInstance), |
| m_fInReset(fInReset) |
| { |
| } |
| |
| result_type |
| operator()(argument_type theXPath) const |
| { |
| if (m_fInReset == true) |
| { |
| m_factoryInstance.doReturnObject(theXPath, |
| true); |
| } |
| else |
| { |
| m_factoryInstance.returnObject(theXPath); |
| } |
| } |
| |
| private: |
| |
| XPathFactory& m_factoryInstance; |
| |
| const bool m_fInReset; |
| }; |
| |
| friend struct DeleteXPathFunctor; |
| |
| protected: |
| |
| virtual bool |
| doReturnObject( |
| const XPath* theXPath, |
| bool fInReset = false) = 0; |
| }; |
| |
| |
| |
| /** |
| * Manages the lifetime of an XPath instance. |
| */ |
| class XPathGuard |
| { |
| public: |
| |
| /** |
| * Construct an XPathGuard instance from a factory object and an XPath. |
| * |
| * @param theFactory object that manages lifetime of XPaths |
| * @param theXPath pointer to XPath managed |
| */ |
| XPathGuard( |
| XPathFactory& theFactory, |
| const XPath* theXPath) : |
| m_factory(&theFactory), |
| m_object(theXPath) |
| { |
| } |
| |
| // Note that copy construction transfers ownership, just |
| // as std::auto_ptr. |
| XPathGuard(XPathGuard& theRHS) |
| { |
| // Release the current object... |
| release(); |
| |
| // Copy the factory and object pointers... |
| m_factory = theRHS.m_factory; |
| m_object = theRHS.m_object; |
| |
| // The source object no longer points to |
| // the object... |
| theRHS.m_factory = 0; |
| theRHS.m_object = 0; |
| } |
| |
| ~XPathGuard() |
| { |
| reset(); |
| } |
| |
| /** |
| * Retrieve the object pointer (must not be null) |
| * |
| * @return pointer to XPath |
| */ |
| const XPath* |
| operator->() const |
| { |
| assert(m_object != 0); |
| |
| return m_object; |
| } |
| |
| /** |
| * Retrieve the object pointer (may be null) |
| * |
| * @return pointer to XPath |
| */ |
| const XPath* |
| get() const |
| { |
| return m_object; |
| } |
| |
| /** |
| * Return the referenced object to the factory and set pointers to null. |
| */ |
| void |
| reset() |
| { |
| if (m_object != 0) |
| { |
| assert(m_factory != 0); |
| |
| m_factory->returnObject(m_object); |
| |
| m_object = 0; |
| } |
| |
| m_factory = 0; |
| } |
| |
| /** |
| * Transfers ownership of XPath to caller |
| * |
| * @return pointer to XPath |
| */ |
| const XPath* |
| release() |
| { |
| const XPath* const theTemp = m_object; |
| |
| m_object = 0; |
| |
| return theTemp; |
| } |
| |
| private: |
| |
| XPathGuard& |
| operator=(const XPathGuard&); |
| |
| bool |
| operator==(const XPathGuard&) const; |
| |
| |
| // Data members... |
| XPathFactory* m_factory; |
| const XPath* m_object; |
| }; |
| |
| |
| |
| XALAN_CPP_NAMESPACE_END |
| |
| |
| |
| #endif // XPATHFACTORY_HEADER_GUARD_1357924680 |