将以下linuxC++代码封装成一个宏定义,{rapidjson::Document doc; doc.SetObject(); auto allocator = doc.GetAllocator(); doc.AddMember("filename", __FILE__, allocator); ... rapidjson::StringBuffer jsonbuffer; rapidjson::Writer<rapidjson::StringBuffer> writer(jsonbuffer); doc.Accept(writer); JSONLOG(jsonbuffer.GetString());}
时间: 2024-03-05 18:49:25 浏览: 13
可以封装成如下宏定义:
```
#define JSONLOG(msg) { \
rapidjson::Document doc; \
doc.SetObject(); \
auto allocator = doc.GetAllocator(); \
doc.AddMember("filename", __FILE__, allocator); \
doc.AddMember("message", msg, allocator); \
rapidjson::StringBuffer jsonbuffer; \
rapidjson::Writer<rapidjson::StringBuffer> writer(jsonbuffer); \
doc.Accept(writer); \
std::cout << jsonbuffer.GetString() << std::endl; \
}
```
使用时,可以像这样调用:
```
JSONLOG("Hello World!");
```
该宏定义将传入的消息文本转化为 JSON 格式,并输出到控制台。其中,"filename" 字段记录了当前文件名,"message" 字段则记录了传入的消息文本。
相关问题
rapidjson::Value
rapidjson::Value is a class in the RapidJSON library that represents a JSON value. It can store any valid JSON value, such as null, boolean, number, string, array, or object. It is designed to be lightweight and efficient, with a small memory footprint and fast parsing and serialization performance.
The rapidjson::Value class provides a number of methods for accessing and modifying the stored JSON value, including GetBool(), GetInt(), GetDouble(), GetString(), GetArray(), GetObject(), and more. It also supports iteration over arrays and objects using C++11 range-based for loops.
Here is an example of creating a rapidjson::Value object and setting its value to a JSON object with two key-value pairs:
```
rapidjson::Document doc;
doc.SetObject();
rapidjson::Value key1("name", doc.GetAllocator());
rapidjson::Value val1("John", doc.GetAllocator());
doc.AddMember(key1, val1, doc.GetAllocator());
rapidjson::Value key2("age", doc.GetAllocator());
rapidjson::Value val2(30);
doc.AddMember(key2, val2, doc.GetAllocator());
```
This code creates a new JSON object with the keys "name" and "age" and sets their values to "John" and 30, respectively. The rapidjson::Value objects for the keys and values are created using the document's allocator, which manages memory allocation for the JSON values. The AddMember() method is used to add the key-value pairs to the object.
优化代码优化class MemoryManager: def init(self, allocator): self.allocator = allocator def allocate(self, process, request_size): memory_view = self.allocator.memory_view() block_start = None for i, block in enumerate(memory_view): if block is None: if block_start is None: block_start = i if i - block_start + 1 == request_size: self.allocator.allocate_memory(block_start, request_size, process) return block_start else: block_start = None return None
可以考虑对循环进行优化,避免无用的迭代和条件判断。
```
class MemoryManager:
def __init__(self, allocator):
self.allocator = allocator
def allocate(self, process, request_size):
memory_view = self.allocator.memory_view()
block_start = None
for i, block in enumerate(memory_view):
if block is None:
if block_start is None:
block_start = i
if i - block_start + 1 == request_size:
self.allocator.allocate_memory(block_start, request_size, process)
return block_start
else:
block_start = None
return None
```
在这个优化版本中,当找到一个可用的内存块时,只需要检查是否满足请求的大小,如果满足则立即进行分配并返回结果;否则继续搜索下一个内存块。这样可以避免不必要的迭代和条件判断。