Create an example directory and add some code examples.

CMakeLists.txt

@@ -184,3 +184,5 @@ add_subdirectory( src )
 #install the includes
 add_subdirectory( include )
 
+#install the example
+add_subdirectory( example )

example/CMakeLists.txt

@@ -0,0 +1,29 @@
+#vim: et ts =4 sts = 4 sw = 4 tw = 0
+cmake_minimum_required(VERSION 3.1)
+
+set(EXAMPLES
+	readFromString
+	readFromStream
+	stringWrite
+	streamWrite
+   )
+add_definitions(-D_GLIBCXX_USE_CXX11_ABI)
+set_property(DIRECTORY PROPERTY COMPILE_OPTIONS ${EXTRA_CXX_FLAGS})
+
+if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
+	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra ")
+else()	
+	add_definitions(
+	-D_SCL_SECURE_NO_WARNINGS
+	-D_CRT_SECURE_NO_WARNINGS
+	-D_WIN32_WINNT=0x601
+	-D_WINSOCK_DEPRECATED_NO_WARNINGS)
+endif()
+
+foreach (example ${EXAMPLES})
+	add_executable(${example} ${example}/${example}.cpp)
+	target_include_directories(${example} PUBLIC ${CMAKE_SOURCE_DIR}/include)
+	target_link_libraries(${example} jsoncpp_lib)
+endforeach()
+
+add_custom_target(examples ALL DEPENDS ${EXAMPLES})

example/README.md

@@ -0,0 +1,13 @@
+***NOTE*** 
+
+If you get linker errors about undefined references to symbols that involve types in the `std::__cxx11` namespace or the tag
+`[abi:cxx11]` then it probably indicates that you are trying to link together object files that were compiles with different
+values for the _GLIBCXX_USE_CXX11_ABI marco. This commonly happens when linking to a third-party library that was compiled with 
+an older version of GCC. If the third-party library cannot be rebuilt with the new ABI then you need to recompole your code with
+the old ABI,just like :
+**g++ stringWrite.cpp -ljsoncpp -std=c++11 -D_GLIBCXX_USE_CXX11_ABI=0 -o stringWrite**
+
+Not all of uses of the new ABI will cause changes in symbol names,for example a class with a `std::string` member  variable will
+have the same mangled bane whether compiled with the older or new ABI. In order to detect such problems the new types and functions
+asre annotated with the abi_tag attribute,allowing the compiler to warn about potential ABI incompatibilities in code using them.
+Those warnings can be enabled with the `-Wabi-tag` option.

example/readFromStream/errorFormat.json

@@ -0,0 +1,3 @@
+{
+    1: "value"
+}

example/readFromStream/readFromStream.cpp

@@ -0,0 +1,32 @@
+#include "json/json.h"
+#include <fstream>
+#include <iostream>
+/*
+parse from stream,collect comments and capture error info.
+
+$g++ readFromStream.cpp -ljsoncpp -std=c++11 -o readFromStream
+$./readFromStream
+// comment head
+{
+    // comment before
+    "key" : "value"
+}
+// comment after
+// comment tail
+*/
+int main(int argc, char* argv[]) {
+  Json::Value root;
+  std::ifstream ifs;
+  ifs.open(argv[1]);
+  root.clear();
+
+  Json::CharReaderBuilder builder;
+  builder["collectComments"] = true;
+  JSONCPP_STRING errs;
+  if (!parseFromStream(builder, ifs, &root, &errs)) {
+    std::cout << errs << std::endl;
+    return EXIT_FAILURE;
+  }
+  std::cout << root << std::endl;
+  return EXIT_SUCCESS;
+}

example/readFromStream/withComment.json

@@ -0,0 +1,6 @@
+// comment head
+{
+    // comment before
+    "key" : "value"
+    // comment after
+}// comment tail

example/readFromString/readFromString.cpp

@@ -0,0 +1,33 @@
+#include "json/json.h"
+#include <iostream>
+/*
+parse a string to Value object with CharReaderBuilder class or Reader class
+$g++ readFromString.cpp -ljsoncpp -std=c++11 -o readFromString
+$./readFromString
+colin
+20
+*/
+int main() {
+  std::string strRes = R"({"Age": 20, "Name": "colin"})";
+  auto nLen = (int)strRes.length();
+  JSONCPP_STRING err;
+  Json::Value root;
+
+#if 0 // old way
+    Json::Reader myreader;
+    myreader.parse(strRes,root);
+#else // new way
+  Json::CharReaderBuilder builder;
+  std::unique_ptr<Json::CharReader> const reader(builder.newCharReader());
+  if (!reader->parse(strRes.c_str(), strRes.c_str() + nLen, &root, &err)) {
+    std::cout << "error" << std::endl;
+    return EXIT_FAILURE;
+  }
+#endif
+  std::string strName = root["Name"].asString();
+  int strAge = root["Age"].asInt();
+
+  std::cout << strName << std::endl;
+  std::cout << strAge << std::endl;
+  return EXIT_SUCCESS;
+}

example/streamWrite/streamWrite.cpp

@@ -0,0 +1,22 @@
+#include "json/json.h"
+#include <iostream>
+/*
+write the Value object to stream
+$g++ streamWrite.cpp -ljsoncpp -std=c++11 -o streamWrite
+$./streamWrite
+{
+    "Age" : 20,
+    "Name" : "robin"
+}
+*/
+int main() {
+  Json::Value root;
+  Json::StreamWriterBuilder builder;
+  std::unique_ptr<Json::StreamWriter> const writer(builder.newStreamWriter());
+
+  root["Name"] = "robin";
+  root["Age"] = 20;
+  writer->write(root, &std::cout);
+
+  return EXIT_SUCCESS;
+}

example/stringWrite/stringWrite.cpp

@@ -0,0 +1,33 @@
+#include "json/json.h"
+#include <iostream>
+/*
+write a Value object to a string
+$g++ stringWrite.cpp -ljsoncpp -std=c++11 -o stringWrite
+$./stringWrite
+{
+    "action" : "run",
+    "data" :
+    {
+        "number" : 1
+    }
+}
+*/
+int main() {
+
+  Json::Value root;
+  Json::Value t_data;
+
+  root["action"] = "run";
+  t_data["number"] = 1;
+  root["data"] = t_data;
+
+#if 0 // old way
+    Json::FastWriter writer;
+    std::string json_file = writer.write(root);
+#else // new way
+  Json::StreamWriterBuilder builder;
+  std::string json_file = Json::writeString(builder, root);
+#endif
+  std::cout << json_file << std::endl;
+  return EXIT_SUCCESS;
+}

src/lib_json/CMakeLists.txt

@@ -87,7 +87,7 @@ endif()
 # See https://cmake.org/cmake/help/v3.1/prop_gbl/CMAKE_CXX_KNOWN_FEATURES.html#prop_gbl:CMAKE_CXX_KNOWN_FEATURES
 # for complete list of features available
 target_compile_features(jsoncpp_lib PUBLIC
-        cxx_std_11 # Compiler mode is aware of C++ 11.
+#        cxx_std_11 # Compiler mode is aware of C++ 11.
         #MSVC 1900 cxx_alignas # Alignment control alignas, as defined in N2341.
         #MSVC 1900 cxx_alignof # Alignment control alignof, as defined in N2341.
         #MSVC 1900 cxx_attributes # Generic attributes, as defined in N2761.

src/lib_json/json_value.cpp

@@ -1436,8 +1436,7 @@ bool Value::isObject() const { return type() == objectValue; }
 Value::Comments::Comments(const Comments& that)
     : ptr_{cloneUnique(that.ptr_)} {}
 
-Value::Comments::Comments(Comments&& that)
-    : ptr_{std::move(that.ptr_)} {}
+Value::Comments::Comments(Comments&& that) : ptr_{std::move(that.ptr_)} {}
 
 Value::Comments& Value::Comments::operator=(const Comments& that) {
   ptr_ = cloneUnique(that.ptr_);

src/test_lib_json/jsontest.cpp

@@ -378,8 +378,8 @@ void Runner::preventDialogOnCrash() {
   _CrtSetReportHook(&msvcrtSilentReportHook);
 #endif // if defined(_MSC_VER)
 
-  // @todo investigate this handler (for buffer overflow)
-  // _set_security_error_handler
+// @todo investigate this handler (for buffer overflow)
+// _set_security_error_handler
 
 #if defined(_WIN32)
   // Prevents the system from popping a dialog for debugging if the

src/test_lib_json/main.cpp

@@ -211,14 +211,17 @@ JSONTEST_FIXTURE(ValueTest, objects) {
   JSONTEST_ASSERT_EQUAL(Json::Value(1234), *foundId);
 
   const char unknownIdKey[] = "unknown id";
-  const Json::Value* foundUnknownId = object1_.find(unknownIdKey, unknownIdKey + strlen(unknownIdKey));
+  const Json::Value* foundUnknownId =
+      object1_.find(unknownIdKey, unknownIdKey + strlen(unknownIdKey));
   JSONTEST_ASSERT_EQUAL(nullptr, foundUnknownId);
 
   // Access through demand()
   const char yetAnotherIdKey[] = "yet another id";
-  const Json::Value* foundYetAnotherId = object1_.find(yetAnotherIdKey, yetAnotherIdKey + strlen(yetAnotherIdKey));
+  const Json::Value* foundYetAnotherId =
+      object1_.find(yetAnotherIdKey, yetAnotherIdKey + strlen(yetAnotherIdKey));
   JSONTEST_ASSERT_EQUAL(nullptr, foundYetAnotherId);
-  Json::Value* demandedYetAnotherId = object1_.demand(yetAnotherIdKey, yetAnotherIdKey + strlen(yetAnotherIdKey));
+  Json::Value* demandedYetAnotherId = object1_.demand(
+      yetAnotherIdKey, yetAnotherIdKey + strlen(yetAnotherIdKey));
   JSONTEST_ASSERT(demandedYetAnotherId != nullptr);
   *demandedYetAnotherId = "baz";
 
@@ -2495,7 +2498,7 @@ JSONTEST_FIXTURE(IteratorTest, const) {
   Json::Value const v;
   JSONTEST_ASSERT_THROWS(
       Json::Value::iterator it(v.begin()) // Compile, but throw.
-  );
+      );
 
   Json::Value value;