mirror of
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127 lines
4.6 KiB
Plaintext
127 lines
4.6 KiB
Plaintext
/**
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\mainpage
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\section _intro Introduction
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<a HREF="http://www.json.org/">JSON (JavaScript Object Notation)</a>
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is a lightweight data-interchange format.
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It can represent integer, real number, string, an ordered sequence of value, and
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a collection of name/value pairs.
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Here is an example of JSON data:
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\verbatim
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// Configuration options
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{
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// Default encoding for text
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"encoding" : "UTF-8",
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// Plug-ins loaded at start-up
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"plug-ins" : [
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"python",
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"c++",
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"ruby"
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],
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// Tab indent size
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"indent" : { "length" : 3, "use_space": true }
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}
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\endverbatim
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\section _features Features
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- read and write JSON document
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- attach C and C++ style comments to element during parsing
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- rewrite JSON document preserving original comments
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Notes: Comments used to be supported in JSON but where removed for
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portability (C like comments are not supported in Python). Since
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comments are useful in configuration/input file, this feature was
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preserved.
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\section _example Code example
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\code
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Json::Value root; // will contains the root value after parsing.
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Json::Reader reader;
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bool parsingSuccessful = reader.parse( config_doc, root );
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if ( !parsingSuccessful )
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{
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// report to the user the failure and their locations in the document.
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std::cout << "Failed to parse configuration\n"
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<< reader.getFormattedErrorMessages();
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return;
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}
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// Get the value of the member of root named 'encoding', return 'UTF-8' if there is no
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// such member.
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std::string encoding = root.get("encoding", "UTF-8" ).asString();
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// Get the value of the member of root named 'encoding', return a 'null' value if
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// there is no such member.
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const Json::Value plugins = root["plug-ins"];
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for ( int index = 0; index < plugins.size(); ++index ) // Iterates over the sequence elements.
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loadPlugIn( plugins[index].asString() );
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setIndentLength( root["indent"].get("length", 3).asInt() );
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setIndentUseSpace( root["indent"].get("use_space", true).asBool() );
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// ...
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// At application shutdown to make the new configuration document:
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// Since Json::Value has implicit constructor for all value types, it is not
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// necessary to explicitly construct the Json::Value object:
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root["encoding"] = getCurrentEncoding();
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root["indent"]["length"] = getCurrentIndentLength();
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root["indent"]["use_space"] = getCurrentIndentUseSpace();
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Json::StyledWriter writer;
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// Make a new JSON document for the configuration. Preserve original comments.
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std::string outputConfig = writer.write( root );
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// You can also use streams. This will put the contents of any JSON
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// stream at a particular sub-value, if you'd like.
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std::cin >> root["subtree"];
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// And you can write to a stream, using the StyledWriter automatically.
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std::cout << root;
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\endcode
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\section _pbuild Build instructions
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The build instructions are located in the file
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<a HREF="README.txt">README.txt</a> in the top-directory of the project.
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Permanent link to the latest revision of the file in subversion:
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<a HREF="http://jsoncpp.svn.sourceforge.net/viewvc/jsoncpp/trunk/jsoncpp/README.txt?view=markup">latest README.txt</a>
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\section _pdownload Download
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The sources can be downloaded from
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<a HREF="http://sourceforge.net/projects/jsoncpp/files/">SourceForge download page</a>.
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The latest version of the source is available in the project's subversion repository:
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<a HREF="http://jsoncpp.svn.sourceforge.net/svnroot/jsoncpp/trunk/">
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http://jsoncpp.svn.sourceforge.net/svnroot/jsoncpp/trunk/</a>
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To checkout the source, see the following
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<a HREF="http://sourceforge.net/scm/?type=svn&group_id=144446">instructions</a>.
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\section _news What's New?
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The description of latest changes can be found in
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<a HREF="NEWS.txt">NEWS.txt</a> in the top-directory of the project.
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Permanent link to the latest revision of the file in subversion:
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<a HREF="http://svn.sourceforge.net/viewcvs.cgi/jsoncpp/README.txt?view=markup">latest NEWS.txt</a>
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\section _plinks Project links
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- <a HREF="http://jsoncpp.sourceforge.net">json-cpp home</a>
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- <a HREF="http://www.sourceforge.net/projects/jsoncpp/">json-cpp sourceforge project</a>
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\section _rlinks Related links
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- <a HREF="http://www.json.org/">JSON</a> Specification and alternate language implementations.
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- <a HREF="http://www.yaml.org/">YAML</a> A data format designed for human readability.
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- <a HREF="http://www.cl.cam.ac.uk/~mgk25/unicode.html">UTF-8 and Unicode FAQ</a>.
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\section _license License
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See file <a HREF="LICENSE">LICENSE</a> in the top-directory of the project.
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Basically JsonCpp is licensed under MIT license, or public domain if desired
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and recognized in your jurisdiction.
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\author Baptiste Lepilleur <blep@users.sourceforge.net>
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*/
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