jvalue — Fast C++ JSON & Apple Plist (bplist) Library

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High-performance C++11 JSON parser / writer with native Apple Property List (XML plist + binary bplist) support. Header + source drop-in, zero dependencies, MIT licensed.

Keywords: C++ JSON library · C++ plist parser · bplist reader · binary plist C++ · Apple Property List · JSON serialization C++11 · lightweight JSON · move semantics · single-file JSON library.

A single-library C++11 value container with serialization to JSON and Apple Property List (both XML plist and binary bplist). One in-memory representation (jvalue), four readers/writers, zero external dependencies.

Why jvalue?

• 📦 Drop-in: copy 2 files (json.{h,cpp}) into any C++11 project
• 🍎 Apple plist first-class: read/write XML .plistand binary .bplist with auto-detect
• 🧩 One data model for JSON and plist — parse JSON, save as bplist, or vice versa
• 🪶 Zero dependencies, standard C++11, builds with GCC / Clang / MSVC
• 🔒 Bounds-checked binary plist parser, MAX_DEPTH = 256 recursion guard

Features

• Dynamically-typed value: null / bool / int64 / double / string / array / object / date / data
• JSON read / compact write / pretty-print (style_write)
• Apple plist read/write — XML and binary bplist share the same jvalue tree
• Auto-vivifying operator[] for ergonomic construction
• Move semantics (jvalue&&) — zero-cost ownership transfer
• Built-in Base64 helper (jbase64) for binary data fields
• C++11, standard library only, builds with g++ / clang++ / MSVC

Build

make # produces ./jvalue (demo binary)
make test# builds the test suite (.build/test)
make clean

Or drop src/json.{h,cpp} into your own project — no other files are required.

Requirements: C++11 compiler. The Makefile uses g++ -Wall -O2 -std=c++11.

Quick start

#include"json.h"intmain() {
jvalue jv;
jv["happy"] = true;
jv["name"] = "Niels";
jv["answer"]["everything"] = 66;
printf("%s\n", jv.style_write().c_str());
return0;
}

Output (keys in insertion order):

{
"happy": true,
"name": "Niels",
"answer": {
"everything": 66
}
}

Usage

Reading JSON

jvalue jv;
string err;
if (jv.read(text, &err)) {
int n = jv["count"]; // implicit conversion
string name = jv["user"]["name"];
for (size_t i = 0; i < jv["items"].size(); i++) {
const jvalue& item = jv["items"].at(i);
// ...
}
}

Writing JSON

string compact = jv.write(); // minified
string pretty = jv.style_write(); // indented
jv.write_to_file("out.json");
jv.style_write_to_file("pretty.json");

Building values

jvalue arr(jvalue::E_ARRAY);
arr.push_back(1);
arr.push_back("two");
arr.push_back(3.14);
jvalue obj;
obj["list"] = arr;
obj["flag"] = true;

Indexing into a non-container promotes it: jv["a"]["b"] = 1 will turn jv and jv["a"] into objects automatically.

Move semantics

jvalue a;
a["data"] = build_large_tree();
jvalue b = std::move(a); // zero-cost, a becomes null

Apple Property Lists

jvalue pv;
pv.read_plist_from_file("Info.plist"); // auto-detects XML vs. binary
string xml; pv.write_plist(xml); // XML plist
string bin; pv.write_bplist(bin); // binary bplist
pv.style_write_plist_to_file("Info.plist");
pv.write_bplist_to_file("Info.bplist");

Binary data & dates

jv["icon"].assign_data(bytes, size); // stored as raw bytes, emitted as base64
string raw = jv["icon"].as_data();
jv["created"].assign_date(time(NULL));
time_t t = jv["created"].as_date();

In JSON output, data and date are serialized as strings (base64 / ISO-ish). In plist output they use the native <data> and <date> tags.

API overview

Area	Class / methods
Value container	jvalue — typed accessors as_int / as_bool / as_string / as_data / ...
JSON I/O	jvalue::read, write, style_write, *_to_file
Plist I/O (XML)	jvalue::read_plist, write_plist, style_write_plist
Plist I/O (bin)	jvalue::read_plist (auto-detect), write_bplist, write_bplist_to_file
Base64	jbase64::encode / decode, or use jvalue::assign_data / as_data

See src/json.h for the full surface.

Repository layout

src/
json.h / json.cpp # jvalue + flat_map + jreader/jwriter + jpreader/jpwriter + jbase64
test/
test.cpp # 59-case test suite
benchmark.cpp # performance benchmark
main.cpp # usage demo
Makefile

License

Released under the MIT License.