Boost Reflection Library
Introduction
This library provides Java-like Reflection API to C++ language.
First, you should declare which classes to be reflected, via some simple register macros.
These declarations are non-intrusive to the reflected classes themselves, and they could be placed at anywhere (same header file, separate header file, or source file), as long as they appears behind the definitions of the reflected classes.
This non-intrusive feature means you could even declare and reflect classes from third-party libraries, which are normally read-only and closed-source binaries.
Then, you could use the API to find the reflected classes by name, and use them, e.g.
- instantiate objects
- invoke methods upon the objects
Besides the basic reflection, it has other highlighted features:
- Java-like Annotation (could be bound on classes, constructors, methods, fields)
- Java-like Object Proxy (C++ interface based, could be used to implement somehow AOP framework)
- Support dynamic loaded library (you could reflect classes declared and compiled within libraries)
Usage
Build & Test
prerequisite
boost >= 1.46 (header files only)
cmake >= 2.8.8
gcc >= 4.6 (for Linux)
vc2008 or later versions (for Windows)
Windows
- install vc2008 or later versions (for later versions, you need to adjust batch files)
- invoke
build.bat - invoke
test.bat
Linux
mkdir build
cd build
cmake -DCMAKE_BUILD_TYPE:STRING=Release ../
make
make test
Install & Run Example
Windows
- download and install NSIS (Nullsoft Scriptable Install System)
- invoke
package.bat - invoke
build/boost-reflection-1.0.0-win32.exe - cd into
C:\Program Files\boost-reflection\example\ioc - invoke
test_ioc -xml driver_manager.xml -xml foo.xml -xml bar.xml -lib foo.dll -lib bar.dll - invoke
test_annotation_mvc -xml mvc_dispatcher.xml
Linux
mkdir build
cd build
cmake -DCMAKE_BUILD_TYPE:STRING=Release ../
make
make install
ldconfig
cd /usr/local/share/boost-reflection/example/ioc
LD_LIBRARY_PATH=./ ./test_ioc -xml driver_manager.xml -xml foo.xml -xml bar.xml -lib libfoo.so -lib libbar.so
LD_LIBRARY_PATH=./ ./test_annotation_mvc -xml mvc_dispatcher.xml
API
register macros
basic declaration
namespace test {
class AccountItf {
public:
virtual std::string getId() = 0;
virtual void setId(std::string id) = 0;
virtual ~AccountItf() {}
};
BOOST_REFL_INTERFACE(
(test)(AccountItf),
BOOST_REFL_INTERFACE_METHOD(getId, std::string,
BOOST_REFL_INTERFACE_METHOD_NO_PARAMS
)
BOOST_REFL_INTERFACE_METHOD(setId, void,
BOOST_REFL_INTERFACE_METHOD_PARAMS(
BOOST_REFL_INTERFACE_METHOD_PARAM(std::string, id)
)
)
)
class AccountImpl : public AccountItf {
public:
AccountImpl() : age(0) {}
AccountImpl(std::string id, unsigned int age) : age(age), id(id) {}
static void echo(AccountImpl* acct, std::string banner) {
std::cout << banner + ": " << acct->getId() << std::endl;
}
std::string getId() {
return id;
}
void setId(std::string id) {
this->id = id;
}
public:
unsigned int age;
private:
std::string id;
};
BOOST_REFL_CLASS (
(test)(AccountImpl),
//derived Inteface
BOOST_REFL_IMPLEMENT_INTERFACE( (test)(AccountItf) )
//constructors
BOOST_REFL_CONSTRUCTOR()
BOOST_REFL_CONSTRUCTOR(std::string id, unsigned int age)
//static methods
BOOST_REFL_STATIC_METHOD(echo, void (AccountImpl* acct, std::string banner))
//fields
BOOST_REFL_FIELD(age, unsigned int)
)
} //namespace testdeclaration with annotation
// Annotation definitions
BOOST_REFL_DEF_ANNOTATION(
(tags)(ControllerTag),
BOOST_REFL_DEF_ANNOTATION_ELEM(std::list<std::string>, capabilities)
BOOST_REFL_DEF_ANNOTATION_ELEM_DEFAULT(std::string, desc, "NO DESC")
)
struct ComponenetInfo {
int id;
std::string desc;
ComponenetInfo() {}
ComponenetInfo(int id, std::string desc) : id(id), desc(desc) {}
};
BOOST_REFL_DEF_ANNOTATION(
(tags)(ComponentTag),
BOOST_REFL_DEF_ANNOTATION_ELEM(ComponenetInfo, info)
BOOST_REFL_DEF_ANNOTATION_ELEM(int, hash)
)
BOOST_REFL_DEF_SIMPLE_ANNOTATION(
(tags)(DummyTag)
)
namespace foo {
struct MyController {
void echo(std::string banner) {
std::cout << "FooController echo: " << banner << std::endl;
}
void reset() {
std::cout << "FooController reset" << std::endl;
}
};
}
BOOST_REFL_CLASS_WITH_ANNOTATION (
//class name sequence
(foo)(MyController),
//class-level annotation
BOOST_REFL_ANNOTATION (
(tags)(ControllerTag),
(capabilities = make_list<std::string>("CAN_ECHO", "CAN_RESET"))
)
//another class-level annotation
BOOST_REFL_ANNOTATION (
(tags)(ComponentTag),
(info = ComponenetInfo(1, "any description"))
(hash = 23243)
),
//default constructor with annotation
BOOST_REFL_CONSTRUCTOR_WITH_ANNOTATION (
(),
BOOST_REFL_SIMPLE_ANNOTATION (
(tags)(DummyTag)
)
)
//methods
BOOST_REFL_METHOD(echo, void(std::string banner))
BOOST_REFL_METHOD(reset, void())
)Class
The class Class represents the reflected class.
class Class {
public:
//
//find reflected class via full qualified class name
//
static Class forObject(any object);
static Class forName(const std::string& name);
static Class forTypeName(const std::string& name);
static std::list<Class> forNamespace(const std::string& ns);
static Container forContainerObject(any object);
static Container forContainerName(const std::string& name);
//
//object new/delete shortcuts
//
any newInstance(std::vector<any> args);
any newInstance(any arg1, any arg2, ...);
template<class T> T newInstance(any arg1, any arg2, ...);
void deleteInstance(any obj);
//
//method invocation shortcuts
//
any invoke(any obj, const std::string& methodName, any arg1, ...);
any invokeStatic(const std::string& methodName, any arg1, ...);
any invoke(any obj, const std::string& methodName, const std::vector<any>& args);
any invokeStatic(const std::string& methodName, const std::vector<any>& args);
//
//field access shortcuts
//
any get(any obj, const std::string& fieldName);
void set(any obj, const std::string& fieldName, any data);
//
//constructor query
//
std::list<Constructor> getConstructors();
Constructor getConstructor(const TypeInfoArray& arg_type_array);
Constructor getConstructor();
Destructor getDestructor();
//
//method query
//
std::list<Method> getMethods();
Method getMethod(const std::string& methodName, const TypeInfoArray& arg_type_array);
Method getMethod(const std::string& methodName;
Method getStaticMethod(const std::string& methodName);
Method getStaticMethod(const std::string& methodName, const TypeInfoArray& arg_type_array);
//
//field query
//
std::list<Field> getFields();
Field getField(const std::string& fieldName);
//
//create object proxy
//
ProxyBase* createProxy(InvocationHandler* h);
};Method
The class Method represents the reflected method.
class Method {
public:
std::string getName() const;
const TypeInfoArray& getParameterTypes() const;
const std::type_info& getResultType() const;
std::string getSignature() const;
bool isStatic() const;
any invoke(any obj, const std::vector<any>& args) const;
any invokeStatic(std::vector<any> args) const;
any invoke(any obj, any arg1, ...) const;
any invokeStatic(any arg1, ...) const;
};