1//
2// URIStreamOpener.h
3//
4// Library: Foundation
5// Package: URI
6// Module: URIStreamOpener
7//
8// Definition of the URIStreamOpener class.
9//
10// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
11// and Contributors.
12//
13// SPDX-License-Identifier: BSL-1.0
14//
15
16
17#ifndef Foundation_URIStreamOpener_INCLUDED
18#define Foundation_URIStreamOpener_INCLUDED
19
20
21#include "Poco/Foundation.h"
22#include "Poco/Mutex.h"
23#include <istream>
24#include <map>
25
26
27namespace Poco {
28
29
30class URI;
31class URIStreamFactory;
32class Path;
33
34
35class Foundation_API URIStreamOpener
36 /// The URIStreamOpener class is used to create and open input streams
37 /// for resourced identified by Uniform Resource Identifiers.
38 ///
39 /// For every URI scheme used, a URIStreamFactory must be registered.
40 /// A FileStreamFactory is automatically registered for file URIs.
41{
42public:
43 enum
44 {
45 MAX_REDIRECTS = 10
46 };
47
48 URIStreamOpener();
49 /// Creates the URIStreamOpener and registers a FileStreamFactory
50 /// for file URIs.
51
52 ~URIStreamOpener();
53 /// Destroys the URIStreamOpener and deletes all registered
54 /// URI stream factories.
55
56 std::istream* open(const URI& uri) const;
57 /// Tries to create and open an input stream for the resource specified
58 /// by the given uniform resource identifier.
59 ///
60 /// If no URIStreamFactory has been registered for the URI's
61 /// scheme, a UnknownURIScheme exception is thrown.
62 /// If the stream cannot be opened for any reason, an
63 /// IOException is thrown.
64 ///
65 /// The given URI must be a valid one. This excludes file system paths.
66 ///
67 /// Whoever calls the method is responsible for deleting
68 /// the returned stream.
69
70 std::istream* open(const std::string& pathOrURI) const;
71 /// Tries to create and open an input stream for the resource specified
72 /// by the given path or uniform resource identifier.
73 ///
74 /// If the stream cannot be opened for any reason, an
75 /// Exception is thrown.
76 ///
77 /// The method first tries to interpret the given pathOrURI as an URI.
78 /// If this fails, the pathOrURI is treated as local filesystem path.
79 /// If this also fails, an exception is thrown.
80 ///
81 /// Whoever calls the method is responsible for deleting
82 /// the returned stream.
83
84 std::istream* open(const std::string& basePathOrURI, const std::string& pathOrURI) const;
85 /// Tries to create and open an input stream for the resource specified
86 /// by the given path or uniform resource identifier.
87 ///
88 /// pathOrURI is resolved against basePathOrURI (see URI::resolve() and
89 /// Path::resolve() for more information).
90 ///
91 /// If the stream cannot be opened for any reason, an
92 /// Exception is thrown.
93 ///
94 /// Whoever calls the method is responsible for deleting
95 /// the returned stream.
96
97 void registerStreamFactory(const std::string& scheme, URIStreamFactory* pFactory);
98 /// Registers a URIStreamFactory for the given scheme. If another factory
99 /// has already been registered for the scheme, an ExistsException is thrown.
100 ///
101 /// The URIStreamOpener takes ownership of the factory and deletes it when it is
102 /// no longer needed (in other words, when the URIStreamOpener is deleted).
103
104 void unregisterStreamFactory(const std::string& scheme);
105 /// Unregisters and deletes the URIStreamFactory for the given scheme.
106 ///
107 /// Throws a NotFoundException if no URIStreamFactory has been registered
108 /// for the given scheme.
109
110 bool supportsScheme(const std::string& scheme);
111 /// Returns true iff a URIStreamFactory for the given scheme
112 /// has been registered.
113
114 static URIStreamOpener& defaultOpener();
115 /// Returns a reference to the default URIStreamOpener.
116
117protected:
118 std::istream* openFile(const Path& path) const;
119 std::istream* openURI(const std::string& scheme, const URI& uri) const;
120
121private:
122 URIStreamOpener(const URIStreamOpener&);
123 URIStreamOpener& operator = (const URIStreamOpener&);
124
125 typedef std::map<std::string, URIStreamFactory*> FactoryMap;
126
127 FactoryMap _map;
128 mutable FastMutex _mutex;
129};
130
131
132} // namespace Poco
133
134
135#endif // Foundation_URIStreamOpener_INCLUDED
136