ACE/ace/XML_Utils/XML_Schema_Resolver.h

   1 /**
   2  * @file XML_Schema_Resolver.h
   3  * @author Will Otte <wotte@dre.vanderbilt.edu>
   4  *
   5  * Resolves schema locations.
   6  */
   7
   8 #ifndef ACE_XML_SCHEMA_RESOLVER_H
   9 #define ACE_XML_SCHEMA_RESOLVER_H
  10 #include /**/ "ace/pre.h"
  11
  12 #if !defined (ACE_LACKS_PRAGMA_ONCE)
  13 #pragma once
  14 #endif /* ACE_LACKS_PRAGMA_ONCE */
  15
  16 #include "XML_Utils_Export.h"
  17 #include "XercesString.h"
  18
  19 #include <xercesc/sax/EntityResolver.hpp>
  20 #include <vector>
  21 #include <string>
  22
  23 using namespace xercesc;
  24
  25 namespace XML
  26 {
  27   // forward decl.
  28   struct NoOp_Resolver;
  29
  30   /**
  31     * @class XML_Schema_Resolver
  32     * @brief Resolves schema locations
  33     *
  34     * Template argument Resolver should be a functor with an operation
  35     * const ACE_TCHAR * operator () (...arguments from resolveEntity...)
  36     */
  37   template <typename Resolver = NoOp_Resolver>
  38   class XML_Schema_Resolver
  39     : public virtual EntityResolver
  40   {
  41   public:
  42     XML_Schema_Resolver (void);
  43
  44     XML_Schema_Resolver (Resolver &resolver);
  45
  46     /// This function is called by the Xerces infrastructure to
  47     /// actually resolve the location of a schema.
  48     virtual InputSource * resolveEntity (const XMLCh *const publicId,
  49                                          const XMLCh *const systemId);
  50
  51     Resolver &get_resolver (void);
  52
  53   private:
  54     XML_Schema_Resolver (XML_Schema_Resolver<Resolver> &);
  55
  56     Resolver resolver_;
  57   };
  58
  59   /**
  60     * @class NoOp_Resolver
  61     * @brief Resolver that does nothing.
  62     */
  63   struct NoOp_Resolver
  64   {
  65     const XMLCh* operator() (const XMLCh *const,
  66                               const XMLCh *const systemId) const
  67     { return systemId; };
  68   };
  69
  70   /**
  71     * @class Basic_Resolver
  72     * @brief Resolves a schema location from a fixed path.
  73     */
  74   struct Basic_Resolver
  75   {
  76     Basic_Resolver (const ACE_TCHAR *path);
  77
  78     XMLCh* operator() (const XMLCh *const publicId,
  79                         const XMLCh *const systemId) const;
  80     XStr path_;
  81   };
  82
  83   /**
  84     * @class Environment_Resolver
  85     * @brief Resolves a schema location from a path from an environment variable.
  86     */
  87   struct XML_Utils_Export Environment_Resolver
  88   {
  89     Environment_Resolver (void);
  90
  91     Environment_Resolver (const ACE_TCHAR *variable,
  92                           const ACE_TCHAR *path);
  93
  94     void add_path (const ACE_TCHAR *variable,
  95                     const ACE_TCHAR *path);
  96
  97     XMLCh* operator() (const XMLCh *const publicId,
  98                         const XMLCh *const systemId) const;
  99
 100     std::vector<XStr> paths_;
 101   };
 102 }
 103
 104 #include "XML_Schema_Resolver.tpp"
 105
 106 #include /**/ "ace/post.h"
 107
 108 #endif /*  ACE_XML_SCHEMA_RESOLVER_H */