Generic callback thread implementation. More...

#include <wpi/util/jni_util.hpp>

Inheritance diagram for wpi::util::java::JCallbackThread< T >:

Public Member Functions
void	Main () override
Public Member Functions inherited from wpi::util::SafeThread
void	Stop () override
Public Member Functions inherited from wpi::util::SafeThreadBase
virtual	~SafeThreadBase ()=default

Public Attributes
std::queue< T >	m_queue
jobject	m_func = nullptr
jmethodID	m_mid
Public Attributes inherited from wpi::util::SafeThread
wpi::util::condition_variable	m_cond
Public Attributes inherited from wpi::util::SafeThreadBase
wpi::util::mutex	m_mutex
std::atomic_bool	m_active {true}
std::thread::id	m_threadId

Detailed Description

template<typename T>
class wpi::util::java::JCallbackThread< T >

Generic callback thread implementation.

JNI's AttachCurrentThread() creates a Java Thread object on every invocation, which is both time inefficient and causes issues with Eclipse (which tries to keep a thread list up-to-date and thus gets swamped).

Instead, this class attaches just once. When a hardware notification occurs, a condition variable wakes up this thread and this thread actually makes the call into Java.

The template parameter T is the message being passed to the callback, but also needs to provide the following functions: static JavaVM* GetJVM(); static const char* GetName(); void CallJava(JNIEnv *env, jobject func, jmethodID mid);