Night Crue
JSON library based on JSMN lib
Dependents: ATT_WNCInterface_Info WNCInterface_HTTP_example NerfUS-Coord Mbed_Prototype_copy_4_INNO_day_15_6_2017 ... more
C++ JSON wrapper over JSMN lib (https://github.com/zserge/jsmn).
This C++ Class is a set of common tools/procedures as a C++ wrapper over JSMN JSON parser library. It is intended to provide the boiler-plate code, with intentions to reduce code clutter, in more of C++ fashion.
In contrast to original library, Json is intended to work strictly with valid JSON structures. Non-standard JSON structures should result in an error.
This class works explicitly on the indices returned by underlying JSMN library. In the scope of this class, its function parameters, return types, and documentation, the term 'index' will always mean the index of JSMN tokens, parsed by the Json constructor, unless and until explicitly mentioned otherwise.
Json.h@4:ae34010d87e5, 2016-08-02 (annotated)
- Committer:
- faheem_chaudhary
- Date:
- Tue Aug 02 20:21:04 2016 +0000
- Revision:
- 4:ae34010d87e5
- Parent:
- 3:fab591fca1e7
- Child:
- 5:dd98cf00ed9b
Added Key search in flat format
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| mercurywaters | 3:fab591fca1e7 | 1 | #ifndef __JSON_LIB_CLASS_H_ |
| mercurywaters | 3:fab591fca1e7 | 2 | #define __JSON_LIB_CLASS_H_ |
| mercurywaters | 3:fab591fca1e7 | 3 | |
| mercurywaters | 3:fab591fca1e7 | 4 | #include "jsmn.h" |
| mercurywaters | 3:fab591fca1e7 | 5 | #include <stdlib.h> |
| mercurywaters | 3:fab591fca1e7 | 6 | #include <string.h> |
| mercurywaters | 3:fab591fca1e7 | 7 | |
| mercurywaters | 3:fab591fca1e7 | 8 | /** |
| mercurywaters | 3:fab591fca1e7 | 9 | * JSON wrapper over JSMN lib |
| mercurywaters | 3:fab591fca1e7 | 10 | */ |
| mercurywaters | 3:fab591fca1e7 | 11 | |
| mercurywaters | 3:fab591fca1e7 | 12 | class Json |
| mercurywaters | 3:fab591fca1e7 | 13 | { |
| mercurywaters | 3:fab591fca1e7 | 14 | private: |
| mercurywaters | 3:fab591fca1e7 | 15 | const char * source; |
| mercurywaters | 3:fab591fca1e7 | 16 | const size_t sourceLength; |
| mercurywaters | 3:fab591fca1e7 | 17 | jsmntok_t * tokens; |
| mercurywaters | 3:fab591fca1e7 | 18 | int tokenCount; |
| mercurywaters | 3:fab591fca1e7 | 19 | Json ( const Json & other ); |
| mercurywaters | 3:fab591fca1e7 | 20 | |
| mercurywaters | 3:fab591fca1e7 | 21 | public: |
| mercurywaters | 3:fab591fca1e7 | 22 | /** The only constructor allowed. As JSON object will create/allocate |
| mercurywaters | 3:fab591fca1e7 | 23 | * memory for it's working, in favor of small memory fottprints, it |
| mercurywaters | 3:fab591fca1e7 | 24 | * is not allowed to be passed-by-value. So there is no copy or |
| mercurywaters | 3:fab591fca1e7 | 25 | * default constructor |
| mercurywaters | 3:fab591fca1e7 | 26 | * @param jsonString - char string containing JSON data |
| mercurywaters | 3:fab591fca1e7 | 27 | * @param length - length of the jsonString |
| mercurywaters | 3:fab591fca1e7 | 28 | */ |
| mercurywaters | 3:fab591fca1e7 | 29 | Json ( const char * jsonString, size_t length ); |
| mercurywaters | 3:fab591fca1e7 | 30 | virtual ~Json (); |
| mercurywaters | 3:fab591fca1e7 | 31 | |
| faheem_chaudhary | 4:ae34010d87e5 | 32 | int findKeyIndex ( const char * key, const int &startingAt ) const; |
| mercurywaters | 3:fab591fca1e7 | 33 | int findKeyIndexIn ( const char * key, const int &parentIndex ) const; |
| mercurywaters | 3:fab591fca1e7 | 34 | int findChildIndexOf ( const int &parentIndex, const int &startingAt ) const; |
| mercurywaters | 3:fab591fca1e7 | 35 | bool matches ( const int & tokenIndex, const char * value ) const; |
| mercurywaters | 3:fab591fca1e7 | 36 | |
| mercurywaters | 3:fab591fca1e7 | 37 | inline bool isValidJson () const; |
| mercurywaters | 3:fab591fca1e7 | 38 | inline jsmntype_t type ( const int tokenIndex ) const; |
| mercurywaters | 3:fab591fca1e7 | 39 | inline int parent ( const int tokenIndex ) const; |
| mercurywaters | 3:fab591fca1e7 | 40 | inline int childCount ( const int tokenIndex ) const; |
| mercurywaters | 3:fab591fca1e7 | 41 | inline int tokenLength ( const int tokenIndex ) const; |
| mercurywaters | 3:fab591fca1e7 | 42 | inline const char * tokenAddress ( const int tokenIndex ) const; |
| mercurywaters | 3:fab591fca1e7 | 43 | |
| mercurywaters | 3:fab591fca1e7 | 44 | int tokenIntegerValue ( const int tokenIndex ) const; |
| mercurywaters | 3:fab591fca1e7 | 45 | float tokenNumberValue ( const int tokenIndex ) const; |
| mercurywaters | 3:fab591fca1e7 | 46 | |
| mercurywaters | 3:fab591fca1e7 | 47 | inline bool tokenBooleanValue ( const int tokenIndex ) const; |
| mercurywaters | 3:fab591fca1e7 | 48 | |
| mercurywaters | 3:fab591fca1e7 | 49 | // void print () const; |
| faheem_chaudhary | 4:ae34010d87e5 | 50 | |
| faheem_chaudhary | 4:ae34010d87e5 | 51 | static char * unescape ( char * jsonString ); |
| mercurywaters | 3:fab591fca1e7 | 52 | }; |
| mercurywaters | 3:fab591fca1e7 | 53 | |
| mercurywaters | 3:fab591fca1e7 | 54 | inline bool Json::isValidJson () const |
| mercurywaters | 3:fab591fca1e7 | 55 | { |
| mercurywaters | 3:fab591fca1e7 | 56 | return ( tokenCount >= 1 ); |
| mercurywaters | 3:fab591fca1e7 | 57 | } |
| mercurywaters | 3:fab591fca1e7 | 58 | |
| mercurywaters | 3:fab591fca1e7 | 59 | inline jsmntype_t Json::type ( const int tokenIndex ) const |
| mercurywaters | 3:fab591fca1e7 | 60 | { |
| mercurywaters | 3:fab591fca1e7 | 61 | return tokens [ tokenIndex ].type; |
| mercurywaters | 3:fab591fca1e7 | 62 | } |
| mercurywaters | 3:fab591fca1e7 | 63 | |
| mercurywaters | 3:fab591fca1e7 | 64 | inline int Json::parent ( const int tokenIndex ) const |
| mercurywaters | 3:fab591fca1e7 | 65 | { |
| mercurywaters | 3:fab591fca1e7 | 66 | return tokens [ tokenIndex ].parent; |
| mercurywaters | 3:fab591fca1e7 | 67 | } |
| mercurywaters | 3:fab591fca1e7 | 68 | |
| mercurywaters | 3:fab591fca1e7 | 69 | inline int Json::childCount ( const int tokenIndex ) const |
| mercurywaters | 3:fab591fca1e7 | 70 | { |
| mercurywaters | 3:fab591fca1e7 | 71 | return tokens [ tokenIndex ].childCount; |
| mercurywaters | 3:fab591fca1e7 | 72 | } |
| mercurywaters | 3:fab591fca1e7 | 73 | |
| mercurywaters | 3:fab591fca1e7 | 74 | inline int Json::tokenLength ( const int tokenIndex ) const |
| mercurywaters | 3:fab591fca1e7 | 75 | { |
| mercurywaters | 3:fab591fca1e7 | 76 | return tokens [ tokenIndex ].end - tokens [ tokenIndex ].start; |
| mercurywaters | 3:fab591fca1e7 | 77 | } |
| mercurywaters | 3:fab591fca1e7 | 78 | |
| mercurywaters | 3:fab591fca1e7 | 79 | inline const char * Json::tokenAddress ( const int tokenIndex ) const |
| mercurywaters | 3:fab591fca1e7 | 80 | { |
| mercurywaters | 3:fab591fca1e7 | 81 | return source + tokens [ tokenIndex ].start; |
| mercurywaters | 3:fab591fca1e7 | 82 | } |
| mercurywaters | 3:fab591fca1e7 | 83 | |
| faheem_chaudhary | 4:ae34010d87e5 | 84 | inline bool Json::tokenBooleanValue ( const int tokenIndex ) const |
| faheem_chaudhary | 4:ae34010d87e5 | 85 | { |
| faheem_chaudhary | 4:ae34010d87e5 | 86 | if ( type ( tokenIndex ) == JSMN_PRIMITIVE ) |
| faheem_chaudhary | 4:ae34010d87e5 | 87 | { |
| faheem_chaudhary | 4:ae34010d87e5 | 88 | return matches ( tokenIndex, "true" ); |
| faheem_chaudhary | 4:ae34010d87e5 | 89 | } |
| faheem_chaudhary | 4:ae34010d87e5 | 90 | return false; |
| faheem_chaudhary | 4:ae34010d87e5 | 91 | } |
| faheem_chaudhary | 4:ae34010d87e5 | 92 | |
| mercurywaters | 3:fab591fca1e7 | 93 | #endif |
| mercurywaters | 3:fab591fca1e7 | 94 |
