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Christopher Dunne0d72242007-06-14 17:58:59 +00001/**
2\mainpage
3\section _intro Introduction
4
5<a HREF="http://www.json.org/">JSON (JavaScript Object Notation)</a>
6 is a lightweight data-interchange format.
Christopher Dunne0d72242007-06-14 17:58:59 +00007
8Here is an example of JSON data:
9\verbatim
Christopher Dunn948f2902015-01-25 12:19:30 -060010{
11 "encoding" : "UTF-8",
12 "plug-ins" : [
13 "python",
14 "c++",
15 "ruby"
16 ],
17 "indent" : { "length" : 3, "use_space": true }
18}
19\endverbatim
20<b>JsonCpp</b> supports comments as <i>meta-data</i>:
21\code
Christopher Dunne0d72242007-06-14 17:58:59 +000022// Configuration options
23{
24 // Default encoding for text
25 "encoding" : "UTF-8",
26
27 // Plug-ins loaded at start-up
28 "plug-ins" : [
29 "python",
Christopher Dunn948f2902015-01-25 12:19:30 -060030 "c++", // trailing comment
Christopher Dunne0d72242007-06-14 17:58:59 +000031 "ruby"
32 ],
33
34 // Tab indent size
Christopher Dunn948f2902015-01-25 12:19:30 -060035 // (multi-line comment)
36 "indent" : { /*embedded comment*/ "length" : 3, "use_space": true }
Christopher Dunne0d72242007-06-14 17:58:59 +000037}
Christopher Dunn948f2902015-01-25 12:19:30 -060038\endcode
Christopher Dunne0d72242007-06-14 17:58:59 +000039
40\section _features Features
41- read and write JSON document
Christopher Dunn35bea412014-07-05 12:13:37 -070042- attach C++ style comments to element during parsing
Christopher Dunne0d72242007-06-14 17:58:59 +000043- rewrite JSON document preserving original comments
44
Christopher Dunn948f2902015-01-25 12:19:30 -060045Notes: Comments used to be supported in JSON but were removed for
Baptiste Lepilleure6a77412010-03-11 21:02:26 +000046portability (C like comments are not supported in Python). Since
47comments are useful in configuration/input file, this feature was
48preserved.
49
50\section _example Code example
51
Christopher Dunne0d72242007-06-14 17:58:59 +000052\code
Christopher Dunn948f2902015-01-25 12:19:30 -060053Json::Value root; // will contain the root value after parsing.
Christopher Dunne0d72242007-06-14 17:58:59 +000054Json::Reader reader;
55bool parsingSuccessful = reader.parse( config_doc, root );
56if ( !parsingSuccessful )
57{
58 // report to the user the failure and their locations in the document.
59 std::cout << "Failed to parse configuration\n"
Baptiste Lepilleurb2e8ccc2011-05-01 16:27:55 +000060 << reader.getFormattedErrorMessages();
Christopher Dunne0d72242007-06-14 17:58:59 +000061 return;
62}
63
64// Get the value of the member of root named 'encoding', return 'UTF-8' if there is no
65// such member.
66std::string encoding = root.get("encoding", "UTF-8" ).asString();
67// Get the value of the member of root named 'encoding', return a 'null' value if
68// there is no such member.
69const Json::Value plugins = root["plug-ins"];
70for ( int index = 0; index < plugins.size(); ++index ) // Iterates over the sequence elements.
71 loadPlugIn( plugins[index].asString() );
72
73setIndentLength( root["indent"].get("length", 3).asInt() );
74setIndentUseSpace( root["indent"].get("use_space", true).asBool() );
75
76// ...
77// At application shutdown to make the new configuration document:
78// Since Json::Value has implicit constructor for all value types, it is not
Baptiste Lepilleure6a77412010-03-11 21:02:26 +000079// necessary to explicitly construct the Json::Value object:
Christopher Dunne0d72242007-06-14 17:58:59 +000080root["encoding"] = getCurrentEncoding();
81root["indent"]["length"] = getCurrentIndentLength();
82root["indent"]["use_space"] = getCurrentIndentUseSpace();
83
84Json::StyledWriter writer;
85// Make a new JSON document for the configuration. Preserve original comments.
86std::string outputConfig = writer.write( root );
87
88// You can also use streams. This will put the contents of any JSON
89// stream at a particular sub-value, if you'd like.
90std::cin >> root["subtree"];
91
92// And you can write to a stream, using the StyledWriter automatically.
93std::cout << root;
94\endcode
95
Baptiste Lepilleura11e47d2010-03-12 10:17:46 +000096\section _pbuild Build instructions
Baptiste Lepilleure6a77412010-03-11 21:02:26 +000097The build instructions are located in the file
Christopher Dunn5a651322014-07-05 20:44:33 -070098<a HREF="https://github.com/open-source-parsers/jsoncpp/blob/master/README.md">README.md</a> in the top-directory of the project.
Christopher Dunne0d72242007-06-14 17:58:59 +000099
Christopher Dunn35bea412014-07-05 12:13:37 -0700100The latest version of the source is available in the project's GitHub repository:
Christopher Dunnbef834e2014-07-05 19:05:10 -0700101<a HREF="https://github.com/open-source-parsers/jsoncpp/">
Christopher Dunn35bea412014-07-05 12:13:37 -0700102jsoncpp</a>
Christopher Dunne0d72242007-06-14 17:58:59 +0000103
Baptiste Lepilleur130730f2010-03-13 11:14:49 +0000104\section _news What's New?
105The description of latest changes can be found in
Christopher Dunn5a651322014-07-05 20:44:33 -0700106<a HREF="https://github.com/open-source-parsers/jsoncpp/wiki/NEWS">
107 the NEWS wiki
108</a>.
Christopher Dunne0d72242007-06-14 17:58:59 +0000109
110\section _rlinks Related links
111- <a HREF="http://www.json.org/">JSON</a> Specification and alternate language implementations.
112- <a HREF="http://www.yaml.org/">YAML</a> A data format designed for human readability.
113- <a HREF="http://www.cl.cam.ac.uk/~mgk25/unicode.html">UTF-8 and Unicode FAQ</a>.
114
Christopher Dunn35bea412014-07-05 12:13:37 -0700115\section _plinks Old project links
116- <a href="https://sourceforge.net/projects/jsoncpp/">https://sourceforge.net/projects/jsoncpp/</a>
117- <a href="http://jsoncpp.sourceforge.net">http://jsoncpp.sourceforge.net</a>
118- <a href="http://sourceforge.net/projects/jsoncpp/files/">http://sourceforge.net/projects/jsoncpp/files/</a>
119- <a href="http://jsoncpp.svn.sourceforge.net/svnroot/jsoncpp/trunk/">http://jsoncpp.svn.sourceforge.net/svnroot/jsoncpp/trunk/</a>
120- <a href="http://jsoncpp.sourceforge.net/old.html">http://jsoncpp.sourceforge.net/old.html</a>
121
Christopher Dunne0d72242007-06-14 17:58:59 +0000122\section _license License
Christopher Dunnbef834e2014-07-05 19:05:10 -0700123See file <a href="https://github.com/open-source-parsers/jsoncpp/blob/master/LICENSE"><code>LICENSE</code></a> in the top-directory of the project.
Baptiste Lepilleur7469f1d2010-04-20 21:35:19 +0000124
125Basically JsonCpp is licensed under MIT license, or public domain if desired
126and recognized in your jurisdiction.
Christopher Dunne0d72242007-06-14 17:58:59 +0000127
Christopher Dunn35bea412014-07-05 12:13:37 -0700128\author Baptiste Lepilleur <blep@users.sourceforge.net> (originator)
Christopher Dunne0d72242007-06-14 17:58:59 +0000129*/