library.c : call static method com.statusim.GethService.signalEvent

This commit is contained in:
rom 2016-06-24 17:16:56 +03:00
parent 9272538432
commit 7122e86b18
1 changed files with 155 additions and 0 deletions

155
src/library.c Normal file
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#include <jni.h>
#include <stdint.h>
#include <stdlib.h>
#include <stdbool.h>
bool GethServiceSignalEvent( const char *jsonEvent );
static JavaVM *gJavaVM = NULL;
static jclass JavaClassPtr_GethService = NULL;
static jmethodID JavaMethodPtr_signalEvent = NULL;
static bool JniLibraryInit( JNIEnv *env );
/*!
* @brief Get interface to JNI.
*
* @return true if thread should be detached from JNI.
*/
static bool JniAttach( JNIEnv **env )
{
jint status;
if (gJavaVM == NULL)
{
env = NULL;
}
status = (*gJavaVM)->GetEnv( gJavaVM, (void **)env, JNI_VERSION_1_6);
if (status == JNI_EDETACHED)
{
// attach thread to JNI
(*gJavaVM)->AttachCurrentThread( gJavaVM, (void **)env, NULL );
return false;
}
else if (status != JNI_OK)
{
return false;
}
return true;
}
/*!
* @brief The VM calls JNI_OnLoad when the native library is loaded.
*/
JNIEXPORT jint JNI_OnLoad(JavaVM* vm, void* reserved)
{
bool detach;
JNIEnv *env;
bool result = JNI_VERSION_1_6;
gJavaVM = vm;
// attach thread to JNI
detach = JniAttach( &env );
if (env == NULL)
{
// failed
gJavaVM = NULL;
return 0;
}
if (!JniLibraryInit( env ))
{
// fail loading of JNI library
result = 0;
}
if (detach)
{
// detach thread from JNI
(*gJavaVM)->DetachCurrentThread( gJavaVM );
}
if (result != JNI_VERSION_1_6)
{
gJavaVM = NULL;
}
return result;
}
/*!
* @brief Initialize library.
*/
bool JniLibraryInit( JNIEnv *env )
{
int i;
JavaClassPtr_GethService = (*env)->FindClass( env, "com/statusim/GethService" );
if (JavaClassPtr_GethService == NULL) return false;
JavaClassPtr_GethService = (jclass)(*env)->NewGlobalRef( env, JavaClassPtr_GethService );
if (JavaClassPtr_GethService == NULL) return false;
struct { bool bStatic; jclass classPtr; jmethodID *methodPtr; const char *methodId; const char *params; } javaMethodDescriptors[] =
{
{ true, JavaClassPtr_GethService, &JavaMethodPtr_signalEvent, "signalEvent", "(Ljava/lang/String;)V" },
// { false, JavaClassPtr_GethService, &JavaMethodPtr_someNonStaticMethod, "someNonStaticMethod", "(Ljava/lang/String;)V" },
};
for (i = 0; i < sizeof(javaMethodDescriptors) / sizeof(javaMethodDescriptors[0]); i++)
{
if (javaMethodDescriptors[i].bStatic)
{
*(javaMethodDescriptors[i].methodPtr) = (*env)->GetStaticMethodID( env, javaMethodDescriptors[i].classPtr, javaMethodDescriptors[i].methodId, javaMethodDescriptors[i].params );
}
else
{
*(javaMethodDescriptors[i].methodPtr) = (*env)->GetMethodID( env, javaMethodDescriptors[i].classPtr, javaMethodDescriptors[i].methodId, javaMethodDescriptors[i].params );
}
if (*(javaMethodDescriptors[i].methodPtr) == NULL) return false;
}
return true;
}
/*!
* @brief Calls static method signalEvent of class com.statusim.GethService.
*
* @param jsonEvent - UTF8 string
*/
bool GethServiceSignalEvent( const char *jsonEvent )
{
bool detach;
JNIEnv *env;
// attach thread to JNI
detach = JniAttach( &env );
if (env == NULL)
{
// failed
return false;
}
jstring javaJsonEvent = NULL;
if (jsonEvent != NULL)
{
javaJsonEvent = (*env)->NewStringUTF( env, jsonEvent );
}
(*env)->CallStaticVoidMethod( env, JavaClassPtr_GethService, JavaMethodPtr_signalEvent, javaJsonEvent );
if (javaJsonEvent != NULL) (*env)->DeleteLocalRef( env, javaJsonEvent );
if (detach)
{
// detach thread from JNI
(*gJavaVM)->DetachCurrentThread( gJavaVM );
}
return true;
}