74 lines
1.4 KiB
C++
74 lines
1.4 KiB
C++
/**
|
|
* Copyright (c) 2021 OceanBase
|
|
* OceanBase CE is licensed under Mulan PubL v2.
|
|
* You can use this software according to the terms and conditions of the Mulan PubL v2.
|
|
* You may obtain a copy of Mulan PubL v2 at:
|
|
* http://license.coscl.org.cn/MulanPubL-2.0
|
|
* THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
|
|
* EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
|
|
* MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
|
|
* See the Mulan PubL v2 for more details.
|
|
*/
|
|
|
|
#ifndef _OB_CONST_MAP_INITIALIZER_H
|
|
#define _OB_CONST_MAP_INITIALIZER_H
|
|
|
|
#include "lib/ob_errno.h"
|
|
#include "lib/utility/utility.h"
|
|
|
|
|
|
namespace oceanbase {
|
|
namespace sql {
|
|
|
|
|
|
/**
|
|
* a defined static const map value of class MyClass
|
|
* usually needs to be inited when declearing it
|
|
* ObConstMap helps in this situatition using
|
|
* a init_function
|
|
*
|
|
*/
|
|
|
|
template <typename MyClass>
|
|
class ObConstMap {
|
|
public:
|
|
|
|
typedef int (*InitFunction)(MyClass &member);
|
|
|
|
explicit ObConstMap(InitFunction init_f) : is_inited_(false), init_f_(init_f)
|
|
{
|
|
}
|
|
|
|
int init()
|
|
{
|
|
int ret = common::OB_SUCCESS;
|
|
if (OB_UNLIKELY(is_inited_)) {
|
|
ret = common::OB_INIT_TWICE;
|
|
} else {
|
|
is_inited_ = true;
|
|
ret = init_f_(member_);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
const MyClass &value()
|
|
{
|
|
return member_;
|
|
}
|
|
|
|
protected:
|
|
bool is_inited_;
|
|
InitFunction init_f_;
|
|
MyClass member_;
|
|
};
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
#endif // _OB_CONST_MAP_INITIALIZER_H
|