整理代码

util/xpack/json_data.h

@@ -0,0 +1,115 @@
+/*
+* Copyright (C) 2021 Duowan Inc. All rights reserved.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing,
+* software distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+#ifndef __X_PACK_JSON_DATA_H
+#define __X_PACK_JSON_DATA_H
+
+
+#include "rapidjson_custom.h"
+#include "rapidjson/document.h"
+#include "util.h"
+#include "traits.h"
+
+namespace xpack {
+
+// wrapper for rapidjson::Value.
+// If we use other json parser someday, users won't have to modify the code.
+// Most of the code is copied from rapidjson.
+enum JsonType {
+    kNullType = 0,      //!< null
+    kFalseType = 1,     //!< false
+    kTrueType = 2,      //!< true
+    kObjectType = 3,    //!< object
+    kArrayType = 4,     //!< array 
+    kStringType = 5,    //!< string
+    kNumberType = 6     //!< number
+};
+
+class JsonData {
+    friend class JsonNode;
+    friend class JsonWriter;
+public:
+    JsonData():current(NULL){}
+
+    // check is valid JsonData
+    operator bool() const {
+        return NULL != current;
+    }
+    JsonType Type() const {
+        if (NULL != current) {
+            return static_cast<JsonType>(current->GetType());
+        }
+        return kNullType; // ?
+    }
+    bool IsNull()   const { return NULL==current||current->IsNull(); }
+    bool IsBool()   const { return NULL!=current && current->IsBool(); }
+    bool IsObject() const { return NULL!=current && current->IsObject(); }
+    bool IsArray()  const { return NULL!=current && current->IsArray(); }
+    bool IsNumber() const { return NULL!=current && current->IsNumber(); }
+    bool IsDouble() const { return NULL!=current && current->IsDouble(); }
+    bool IsString() const { return NULL!=current && current->IsString(); }
+    size_t Size() const {return (size_t)current->Size();}
+
+    JsonData operator [](const char *key) const {
+        if (NULL != current && current->IsObject()) {
+            rapidjson::Value::ConstMemberIterator iter = current->FindMember(key);
+            if (iter != current->MemberEnd()) {
+                return JsonData(&iter->value);
+            } // no exception ?
+        }
+        return JsonData();
+    }
+    JsonData operator [](size_t index) const {
+        if (NULL != current && current->IsArray() && index < (size_t)current->Size()) {
+            return JsonData(&(*current)[(rapidjson::SizeType)index]);
+        }
+        return JsonData();
+    }
+
+    std::string String() const; // Implementation in json_encoder.h
+
+    template <typename T>       // For base byte(integer/float/double/bool/std::string), implementation in json_decoder.h
+    T Get() const;
+
+    template <typename T>       // struct, implementation in json_decoder.h
+    bool Get(T &val) const;
+
+private:
+    JsonData(const rapidjson::Value*v):current(v){}
+
+    void reset(const rapidjson::Value *v) {
+        node.reset();
+        allocator.reset();
+        current = NULL;
+        if (NULL != v) {
+            if (v->IsNull()) {
+                node.reset(new rapidjson::Value());
+            } else {
+                allocator.reset(new rapidjson::MemoryPoolAllocator<>());
+                node.reset(new rapidjson::Value(*v, *allocator, true));
+            }
+            current = node.get();
+        }
+    }
+    x_shared_ptr<rapidjson::MemoryPoolAllocator<> > allocator;
+    x_shared_ptr<rapidjson::Value> node; // release node first
+
+    const rapidjson::Value* current;
+};
+
+}
+
+#endif