[Jogl|Nativewindow|Newt]Common: Align all *Common_GetJNIEnv()/_ReleaseJNIEnv() Methods and Usage / Check arguments ..

Since we still don't use inter-module native code sharing, align the JNIEnv get/release methods and usage.

Most beneficary here is OSX and the GLDebugMessageHandle,
both managed the JVM handle on their own - removed now.

Also ensuring that *Common_init(..) is called for all modules on all platforms.

5 files changed, 195 insertions, 138 deletions

diff --git a/src/nativewindow/native/NativewindowCommon.c b/src/nativewindow/native/NativewindowCommon.c
index ec7ee7728..e65f87272 100644
--- a/src/nativewindow/native/NativewindowCommon.c
+++ b/src/nativewindow/native/NativewindowCommon.c
@@ -8,41 +8,24 @@
 static const char * const ClazzNameRuntimeException = "java/lang/RuntimeException";
 static jclass    runtimeExceptionClz=NULL;
 
-void NativewindowCommon_FatalError(JNIEnv *env, const char* msg, ...)
-{
-    char buffer[512];
-    va_list ap;
-
-    va_start(ap, msg);
-    vsnprintf(buffer, sizeof(buffer), msg, ap);
-    va_end(ap);
-
-    fprintf(stderr, "%s\n", buffer);
-    (*env)->FatalError(env, buffer);
-}
-
-void NativewindowCommon_throwNewRuntimeException(JNIEnv *env, const char* msg, ...)
-{
-    char buffer[512];
-    va_list ap;
-
-    va_start(ap, msg);
-    vsnprintf(buffer, sizeof(buffer), msg, ap);
-    va_end(ap);
-
-    (*env)->ThrowNew(env, runtimeExceptionClz, buffer);
-}
+static JavaVM *_jvmHandle = NULL;
+static int _jvmVersion = 0;
 
 int NativewindowCommon_init(JNIEnv *env) {
-    if(NULL==runtimeExceptionClz) {
+    if(NULL==_jvmHandle) {
+        if(0 != (*env)->GetJavaVM(env, &_jvmHandle)) {
+            NativewindowCommon_FatalError(env, "Nativewindow: Can't fetch JavaVM handle");
+        } else {
+            _jvmVersion = (*env)->GetVersion(env);
+        }
         jclass c = (*env)->FindClass(env, ClazzNameRuntimeException);
         if(NULL==c) {
-            NativewindowCommon_FatalError(env, "Nativewindow: can't find %s", ClazzNameRuntimeException);
+            NativewindowCommon_FatalError(env, "Nativewindow: Can't find %s", ClazzNameRuntimeException);
         }
         runtimeExceptionClz = (jclass)(*env)->NewGlobalRef(env, c);
         (*env)->DeleteLocalRef(env, c);
         if(NULL==runtimeExceptionClz) {
-            NativewindowCommon_FatalError(env, "Nativewindow: can't use %s", ClazzNameRuntimeException);
+            NativewindowCommon_FatalError(env, "Nativewindow: Can't use %s", ClazzNameRuntimeException);
         }
         #ifdef STDERR_TO_FILE
             FILE * old_stderr = stderr; 
@@ -54,6 +37,44 @@ int NativewindowCommon_init(JNIEnv *env) {
     return 0;
 }
 
+void NativewindowCommon_FatalError(JNIEnv *env, const char* msg, ...)
+{
+    char buffer[512];
+    va_list ap;
+
+    if( NULL != msg ) {
+        va_start(ap, msg);
+        vsnprintf(buffer, sizeof(buffer), msg, ap);
+        va_end(ap);
+
+        fprintf(stderr, "%s\n", buffer);
+        if(NULL != env) {
+            (*env)->FatalError(env, buffer);
+        }
+    }
+}
+
+void NativewindowCommon_throwNewRuntimeException(JNIEnv *env, const char* msg, ...)
+{
+    char buffer[512];
+    va_list ap;
+
+    if(NULL==_jvmHandle) {
+        NativewindowCommon_FatalError(env, "Nativewindow: NULL JVM handle, call NativewindowCommon_init 1st\n");
+        return;
+    }
+
+    if( NULL != msg ) {
+        va_start(ap, msg);
+        vsnprintf(buffer, sizeof(buffer), msg, ap);
+        va_end(ap);
+
+        if(NULL != env) {
+            (*env)->ThrowNew(env, runtimeExceptionClz, buffer);
+        }
+    }
+}
+
 const char * NativewindowCommon_GetStaticStringMethod(JNIEnv *jniEnv, jclass clazz, jmethodID jGetStrID, char *dest, int destSize, const char *altText) {
     if(NULL != jniEnv && NULL != clazz && NULL != jGetStrID) {
         jstring jstr = (jstring) (*jniEnv)->CallStaticObjectMethod(jniEnv, clazz, jGetStrID);
@@ -75,45 +96,60 @@ const char * NativewindowCommon_GetStaticStringMethod(JNIEnv *jniEnv, jclass cla
 jchar* NativewindowCommon_GetNullTerminatedStringChars(JNIEnv* env, jstring str)
 {
     jchar* strChars = NULL;
-    strChars = calloc((*env)->GetStringLength(env, str) + 1, sizeof(jchar));
-    if (strChars != NULL) {
-        (*env)->GetStringRegion(env, str, 0, (*env)->GetStringLength(env, str), strChars);
+    if( NULL != env && 0 != str ) {
+        strChars = calloc((*env)->GetStringLength(env, str) + 1, sizeof(jchar));
+        if (strChars != NULL) {
+            (*env)->GetStringRegion(env, str, 0, (*env)->GetStringLength(env, str), strChars);
+        }
     }
     return strChars;
 }
 
-JNIEnv* NativewindowCommon_GetJNIEnv (JavaVM * jvmHandle, int jvmVersion, int asDaemon, int * shallBeDetached) {
+JNIEnv* NativewindowCommon_GetJNIEnv (int asDaemon, int * shallBeDetached) {
     JNIEnv* curEnv = NULL;
     JNIEnv* newEnv = NULL;
     int envRes;
 
+    if(NULL==_jvmHandle) {
+        fprintf(stderr, "Nativewindow GetJNIEnv: NULL JVM handle, call NativewindowCommon_init 1st\n");
+        return NULL;
+    }
+
     // retrieve this thread's JNIEnv curEnv - or detect it's detached
-    envRes = (*jvmHandle)->GetEnv(jvmHandle, (void **) &curEnv, jvmVersion) ;
+    envRes = (*_jvmHandle)->GetEnv(_jvmHandle, (void **) &curEnv, _jvmVersion) ;
     if( JNI_EDETACHED == envRes ) {
         // detached thread - attach to JVM
         if( asDaemon ) {
-            envRes = (*jvmHandle)->AttachCurrentThreadAsDaemon(jvmHandle, (void**) &newEnv, NULL);
+            envRes = (*_jvmHandle)->AttachCurrentThreadAsDaemon(_jvmHandle, (void**) &newEnv, NULL);
         } else {
-            envRes = (*jvmHandle)->AttachCurrentThread(jvmHandle, (void**) &newEnv, NULL);
+            envRes = (*_jvmHandle)->AttachCurrentThread(_jvmHandle, (void**) &newEnv, NULL);
         }
         if( JNI_OK != envRes ) {
-            fprintf(stderr, "JNIEnv: can't attach thread: %d\n", envRes);
+            fprintf(stderr, "Nativewindow GetJNIEnv: Can't attach thread: %d\n", envRes);
             return NULL;
         }
         curEnv = newEnv;
     } else if( JNI_OK != envRes ) {
         // oops ..
-        fprintf(stderr, "can't GetEnv: %d\n", envRes);
+        fprintf(stderr, "Nativewindow GetJNIEnv: Can't GetEnv: %d\n", envRes);
         return NULL;
     }
     if (curEnv==NULL) {
-        fprintf(stderr, "env is NULL\n");
+        fprintf(stderr, "Nativewindow GetJNIEnv: env is NULL\n");
         return NULL;
     }
     *shallBeDetached = NULL != newEnv;
     return curEnv;
 }
 
+void NativewindowCommon_ReleaseJNIEnv (int shallBeDetached) {
+    if(NULL == _jvmHandle) {
+        fprintf(stderr, "Nativewindow ReleaseJNIEnv: No JavaVM handle registered, call NativewindowCommon_init(..) 1st");
+    } else if(shallBeDetached) {
+        (*_jvmHandle)->DetachCurrentThread(_jvmHandle);
+    }
+}
+
 int64_t NativewindowCommon_CurrentTimeMillis() {
     struct timeval tv;
     gettimeofday(&tv,NULL);
diff --git a/src/nativewindow/native/NativewindowCommon.h b/src/nativewindow/native/NativewindowCommon.h
index a23fad9fd..f19552e33 100644
--- a/src/nativewindow/native/NativewindowCommon.h
+++ b/src/nativewindow/native/NativewindowCommon.h
@@ -1,3 +1,30 @@
+/**
+ * Copyright 2011 JogAmp Community. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification, are
+ * permitted provided that the following conditions are met:
+ * 
+ *    1. Redistributions of source code must retain the above copyright notice, this list of
+ *       conditions and the following disclaimer.
+ * 
+ *    2. Redistributions in binary form must reproduce the above copyright notice, this list
+ *       of conditions and the following disclaimer in the documentation and/or other materials
+ *       provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY JogAmp Community ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JogAmp Community OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * 
+ * The views and conclusions contained in the software and documentation are those of the
+ * authors and should not be interpreted as representing official policies, either expressed
+ * or implied, of JogAmp Community.
+ */
 
 #ifndef NATIVEWINDOW_COMMON_H
 #define NATIVEWINDOW_COMMON_H 1
@@ -14,7 +41,39 @@ jchar* NativewindowCommon_GetNullTerminatedStringChars(JNIEnv* env, jstring str)
 void NativewindowCommon_FatalError(JNIEnv *env, const char* msg, ...);
 void NativewindowCommon_throwNewRuntimeException(JNIEnv *env, const char* msg, ...);
 
-JNIEnv* NativewindowCommon_GetJNIEnv (JavaVM * jvmHandle, int jvmVersion, int asDaemon, int * shallBeDetached);
+/**
+ *
+ * 1) Init static jvmHandle, jvmVersion and clazz references
+ *    from an early initialization call w/ valid 'JNIEnv * env'
+
+    NativewindowCommon_init(env);
+
+ *
+ * 2) Use current thread JNIEnv or attach current thread to JVM, generating new JNIEnv
+ *
+
+    int asDaemon = 0;
+    int shallBeDetached = 0;
+    JNIEnv* env = NewtCommon_GetJNIEnv(asDaemon, &shallBeDetached);
+    if(NULL==env) {
+        DBG_PRINT("drawRect: null JNIEnv\n");
+        return;
+    }
+    
+ *
+ * 3) Use JNIEnv ..
+ *
+    .. your JNIEnv code here ..
+
+ *
+ * 4) Detach thread from JVM if required, i.e. not attached as daemon!
+ *    Not recommended for recurring _daemon_ threads (performance)
+ *
+    NewtCommon_ReleaseJNIEnv(shallBeDetached);
+ */
+JNIEnv* NativewindowCommon_GetJNIEnv (int asDaemon, int * shallBeDetached);
+
+void NativewindowCommon_ReleaseJNIEnv (int shallBeDetached);
 
 int64_t NativewindowCommon_CurrentTimeMillis();
 
diff --git a/src/nativewindow/native/macosx/OSXmisc.m b/src/nativewindow/native/macosx/OSXmisc.m
index 6a7952eaf..4887cc3cf 100644
--- a/src/nativewindow/native/macosx/OSXmisc.m
+++ b/src/nativewindow/native/macosx/OSXmisc.m
@@ -75,11 +75,9 @@ static const char * const ClazzNameInsetsCstrSignature = "(IIII)V";
 static jclass insetsClz = NULL;
 static jmethodID insetsCstr = NULL;
 
-static int _initialized=0;
-
 JNIEXPORT jboolean JNICALL 
 Java_jogamp_nativewindow_macosx_OSXUtil_initIDs0(JNIEnv *env, jclass _unused) {
-    if(0==_initialized) {
+    if( NativewindowCommon_init(env) ) {
         jclass c;
         c = (*env)->FindClass(env, ClazzNamePoint);
         if(NULL==c) {
@@ -119,7 +117,6 @@ Java_jogamp_nativewindow_macosx_OSXUtil_initIDs0(JNIEnv *env, jclass _unused) {
         if(NULL==runnableRunID) {
             NativewindowCommon_FatalError(env, "FatalError Java_jogamp_newt_driver_macosx_MacWindow_initIDs0: can't fetch %s.run()V", ClazzNameRunnable);
         }
-        _initialized=1;
     }
     return JNI_TRUE;
 }
@@ -775,12 +772,10 @@ JNIEXPORT void JNICALL Java_jogamp_nativewindow_jawt_macosx_MacOSXJAWTWindow_Uns
 @interface MainRunnable : NSObject
 
 {
-    JavaVM *jvmHandle;
-    int jvmVersion;
     jobject runnableObj;
 }
 
-- (id) initWithRunnable: (jobject)runnable jvmHandle: (JavaVM*)jvm jvmVersion: (int)jvmVers;
+- (id) initWithRunnable: (jobject)runnable;
 - (void) jRun;
 
 #ifdef DBG_LIFECYCLE
@@ -794,10 +789,8 @@ JNIEXPORT void JNICALL Java_jogamp_nativewindow_jawt_macosx_MacOSXJAWTWindow_Uns
 
 @implementation MainRunnable
 
-- (id) initWithRunnable: (jobject)runnable jvmHandle: (JavaVM*)jvm jvmVersion: (int)jvmVers
+- (id) initWithRunnable: (jobject)runnable
 {
-    jvmHandle = jvm;
-    jvmVersion = jvmVers;
     runnableObj = runnable;
     return [super init];
 }
@@ -805,7 +798,7 @@ JNIEXPORT void JNICALL Java_jogamp_nativewindow_jawt_macosx_MacOSXJAWTWindow_Uns
 - (void) jRun
 {
     int shallBeDetached = 0;
-    JNIEnv* env = NativewindowCommon_GetJNIEnv(jvmHandle, jvmVersion, 1 /* asDaemon */, &shallBeDetached);
+    JNIEnv* env = NativewindowCommon_GetJNIEnv(1 /* asDaemon */, &shallBeDetached);
     DBG_PRINT2("MainRunnable.1 env: %d\n", (int)(NULL!=env));
     if(NULL!=env) {
         DBG_PRINT2("MainRunnable.1.0\n");
@@ -813,11 +806,9 @@ JNIEXPORT void JNICALL Java_jogamp_nativewindow_jawt_macosx_MacOSXJAWTWindow_Uns
         DBG_PRINT2("MainRunnable.1.1\n");
         (*env)->DeleteGlobalRef(env, runnableObj);
 
-        if (shallBeDetached) {
-            DBG_PRINT2("MainRunnable.1.3\n");
-            // Keep attached on main thread !
-            // (*jvmHandle)->DetachCurrentThread(jvmHandle);
-        }
+        DBG_PRINT2("MainRunnable.1.3\n");
+        // detaching thread not required - daemon
+        // NativewindowCommon_ReleaseJNIEnv(shallBeDetached);
     }
     DBG_PRINT2("MainRunnable.X\n");
 }
@@ -861,17 +852,8 @@ static void RunOnThread (JNIEnv *env, jobject runnable, BOOL onMain, jint delayI
     if ( forkOnMain ) {
         jobject runnableObj = (*env)->NewGlobalRef(env, runnable);
 
-        JavaVM *jvmHandle = NULL;
-        int jvmVersion = 0;
-
-        if(0 != (*env)->GetJavaVM(env, &jvmHandle)) {
-            jvmHandle = NULL;
-        } else {
-            jvmVersion = (*env)->GetVersion(env);
-        }
-
         DBG_PRINT2( "RunOnThread.1.0\n");
-        MainRunnable * mr = [[MainRunnable alloc] initWithRunnable: runnableObj jvmHandle: jvmHandle jvmVersion: jvmVersion];
+        MainRunnable * mr = [[MainRunnable alloc] initWithRunnable: runnableObj];
 
         if( onMain ) {
             [mr performSelectorOnMainThread:@selector(jRun) withObject:nil waitUntilDone:NO];
diff --git a/src/nativewindow/native/win32/GDImisc.c b/src/nativewindow/native/win32/GDImisc.c
index e28f68e7d..bec1d4922 100644
--- a/src/nativewindow/native/win32/GDImisc.c
+++ b/src/nativewindow/native/win32/GDImisc.c
@@ -487,7 +487,7 @@ JNIEXPORT jboolean JNICALL Java_jogamp_nativewindow_windows_GDIUtil_DestroyWindo
 JNIEXPORT jboolean JNICALL Java_jogamp_nativewindow_windows_GDIUtil_initIDs0
   (JNIEnv *env, jclass gdiClazz)
 {
-    if(NativewindowCommon_init(env)) {
+    if( NativewindowCommon_init(env) ) {
         jclass c = (*env)->FindClass(env, ClazzNamePoint);
         if(NULL==c) {
             NativewindowCommon_FatalError(env, "FatalError jogamp_nativewindow_windows_GDIUtil: can't find %s", ClazzNamePoint);
diff --git a/src/nativewindow/native/x11/Xmisc.c b/src/nativewindow/native/x11/Xmisc.c
index 5e6909f6e..247dc1311 100644
--- a/src/nativewindow/native/x11/Xmisc.c
+++ b/src/nativewindow/native/x11/Xmisc.c
@@ -113,68 +113,56 @@ static jmethodID pointCstr = NULL;
 static void _initClazzAccess(JNIEnv *env) {
     jclass c;
 
-    if(!NativewindowCommon_init(env)) return;
-
-    getCurrentThreadNameID = (*env)->GetStaticMethodID(env, X11UtilClazz, "getCurrentThreadName", "()Ljava/lang/String;");
-    if(NULL==getCurrentThreadNameID) {
-        NativewindowCommon_FatalError(env, "FatalError Java_jogamp_nativewindow_x11_X11Lib: can't get method getCurrentThreadName");
-    }
-    dumpStackID = (*env)->GetStaticMethodID(env, X11UtilClazz, "dumpStack", "()V");
-    if(NULL==dumpStackID) {
-        NativewindowCommon_FatalError(env, "FatalError Java_jogamp_nativewindow_x11_X11Lib: can't get method dumpStack");
-    }
-
-    c = (*env)->FindClass(env, ClazzNameBuffers);
-    if(NULL==c) {
-        NativewindowCommon_FatalError(env, "FatalError Java_jogamp_nativewindow_x11_X11Lib: can't find %s", ClazzNameBuffers);
-    }
-    clazzBuffers = (jclass)(*env)->NewGlobalRef(env, c);
-    (*env)->DeleteLocalRef(env, c);
-    if(NULL==clazzBuffers) {
-        NativewindowCommon_FatalError(env, "FatalError Java_jogamp_nativewindow_x11_X11Lib: can't use %s", ClazzNameBuffers);
-    }
-    c = (*env)->FindClass(env, ClazzNameByteBuffer);
-    if(NULL==c) {
-        NativewindowCommon_FatalError(env, "FatalError Java_jogamp_nativewindow_x11_X11Lib: can't find %s", ClazzNameByteBuffer);
-    }
-    clazzByteBuffer = (jclass)(*env)->NewGlobalRef(env, c);
-    (*env)->DeleteLocalRef(env, c);
-    if(NULL==c) {
-        NativewindowCommon_FatalError(env, "FatalError Java_jogamp_nativewindow_x11_X11Lib: can't use %s", ClazzNameByteBuffer);
-    }
-
-    cstrBuffers = (*env)->GetStaticMethodID(env, clazzBuffers, 
-                            ClazzNameBuffersStaticCstrName, ClazzNameBuffersStaticCstrSignature);
-    if(NULL==cstrBuffers) {
-        NativewindowCommon_FatalError(env, "FatalError Java_jogamp_nativewindow_x11_X11Lib: can't create %s.%s %s",
-            ClazzNameBuffers, ClazzNameBuffersStaticCstrName, ClazzNameBuffersStaticCstrSignature);
-    }
+    if( NativewindowCommon_init(env) ) {
+        getCurrentThreadNameID = (*env)->GetStaticMethodID(env, X11UtilClazz, "getCurrentThreadName", "()Ljava/lang/String;");
+        if(NULL==getCurrentThreadNameID) {
+            NativewindowCommon_FatalError(env, "FatalError Java_jogamp_nativewindow_x11_X11Lib: can't get method getCurrentThreadName");
+        }
+        dumpStackID = (*env)->GetStaticMethodID(env, X11UtilClazz, "dumpStack", "()V");
+        if(NULL==dumpStackID) {
+            NativewindowCommon_FatalError(env, "FatalError Java_jogamp_nativewindow_x11_X11Lib: can't get method dumpStack");
+        }
 
-    c = (*env)->FindClass(env, ClazzNamePoint);
-    if(NULL==c) {
-        NativewindowCommon_FatalError(env, "FatalError Java_jogamp_nativewindow_x11_X11Lib: can't find %s", ClazzNamePoint);
-    }
-    pointClz = (jclass)(*env)->NewGlobalRef(env, c);
-    (*env)->DeleteLocalRef(env, c);
-    if(NULL==pointClz) {
-        NativewindowCommon_FatalError(env, "FatalError Java_jogamp_nativewindow_x11_X11Lib: can't use %s", ClazzNamePoint);
-    }
-    pointCstr = (*env)->GetMethodID(env, pointClz, ClazzAnyCstrName, ClazzNamePointCstrSignature);
-    if(NULL==pointCstr) {
-        NativewindowCommon_FatalError(env, "FatalError Java_jogamp_nativewindow_x11_X11Lib: can't fetch %s.%s %s",
-            ClazzNamePoint, ClazzAnyCstrName, ClazzNamePointCstrSignature);
-    }
-}
+        c = (*env)->FindClass(env, ClazzNameBuffers);
+        if(NULL==c) {
+            NativewindowCommon_FatalError(env, "FatalError Java_jogamp_nativewindow_x11_X11Lib: can't find %s", ClazzNameBuffers);
+        }
+        clazzBuffers = (jclass)(*env)->NewGlobalRef(env, c);
+        (*env)->DeleteLocalRef(env, c);
+        if(NULL==clazzBuffers) {
+            NativewindowCommon_FatalError(env, "FatalError Java_jogamp_nativewindow_x11_X11Lib: can't use %s", ClazzNameBuffers);
+        }
+        c = (*env)->FindClass(env, ClazzNameByteBuffer);
+        if(NULL==c) {
+            NativewindowCommon_FatalError(env, "FatalError Java_jogamp_nativewindow_x11_X11Lib: can't find %s", ClazzNameByteBuffer);
+        }
+        clazzByteBuffer = (jclass)(*env)->NewGlobalRef(env, c);
+        (*env)->DeleteLocalRef(env, c);
+        if(NULL==c) {
+            NativewindowCommon_FatalError(env, "FatalError Java_jogamp_nativewindow_x11_X11Lib: can't use %s", ClazzNameByteBuffer);
+        }
 
-static JavaVM *jvmHandle = NULL;
-static int jvmVersion = 0;
+        cstrBuffers = (*env)->GetStaticMethodID(env, clazzBuffers, 
+                                ClazzNameBuffersStaticCstrName, ClazzNameBuffersStaticCstrSignature);
+        if(NULL==cstrBuffers) {
+            NativewindowCommon_FatalError(env, "FatalError Java_jogamp_nativewindow_x11_X11Lib: can't create %s.%s %s",
+                ClazzNameBuffers, ClazzNameBuffersStaticCstrName, ClazzNameBuffersStaticCstrSignature);
+        }
 
-static void setupJVMVars(JNIEnv * env) {
-    if( NULL != env && NULL == jvmHandle ) {
-        if(0 != (*env)->GetJavaVM(env, &jvmHandle)) {
-            jvmHandle = NULL;
+        c = (*env)->FindClass(env, ClazzNamePoint);
+        if(NULL==c) {
+            NativewindowCommon_FatalError(env, "FatalError Java_jogamp_nativewindow_x11_X11Lib: can't find %s", ClazzNamePoint);
+        }
+        pointClz = (jclass)(*env)->NewGlobalRef(env, c);
+        (*env)->DeleteLocalRef(env, c);
+        if(NULL==pointClz) {
+            NativewindowCommon_FatalError(env, "FatalError Java_jogamp_nativewindow_x11_X11Lib: can't use %s", ClazzNamePoint);
+        }
+        pointCstr = (*env)->GetMethodID(env, pointClz, ClazzAnyCstrName, ClazzNamePointCstrSignature);
+        if(NULL==pointCstr) {
+            NativewindowCommon_FatalError(env, "FatalError Java_jogamp_nativewindow_x11_X11Lib: can't fetch %s.%s %s",
+                ClazzNamePoint, ClazzAnyCstrName, ClazzNamePointCstrSignature);
         }
-        jvmVersion = (*env)->GetVersion(env);
     }
 }
 
@@ -201,8 +189,8 @@ static int x11ErrorHandler(Display *dpy, XErrorEvent *e)
             (int)e->request_code, (int)e->minor_code, reqCodeStr);
         fflush(stderr);
 
-        if( NULL != jvmHandle && ( errorHandlerDebug || errorHandlerThrowException ) ) {
-            jniEnv = NativewindowCommon_GetJNIEnv(jvmHandle, jvmVersion, 0 /* asDaemon */, &shallBeDetached);
+        if( errorHandlerDebug || errorHandlerThrowException ) {
+            jniEnv = NativewindowCommon_GetJNIEnv(0 /* asDaemon */, &shallBeDetached);
             if(NULL == jniEnv) {
                 fprintf(stderr, "Nativewindow X11 Error: null JNIEnv");
                 fflush(stderr);
@@ -219,9 +207,7 @@ static int x11ErrorHandler(Display *dpy, XErrorEvent *e)
                                                             e->error_code, errCodeStr, e->display, (int)e->resourceid, (int)e->serial,
                                                             (int)e->request_code, (int)e->minor_code, reqCodeStr);
             }
-            if (shallBeDetached) {
-                (*jvmHandle)->DetachCurrentThread(jvmHandle);
-            }
+            NativewindowCommon_ReleaseJNIEnv(shallBeDetached);
         }
     }
 
@@ -233,7 +219,6 @@ static void NativewindowCommon_x11ErrorHandlerEnable(JNIEnv * env, Display *dpy,
     if(onoff) {
         if(force || NULL==origErrorHandler) {
             XErrorHandler prevErrorHandler;
-            setupJVMVars(env);
             prevErrorHandler = XSetErrorHandler(x11ErrorHandler);
             if(x11ErrorHandler != prevErrorHandler) { // if forced don't overwrite w/ orig w/ our handler
                 origErrorHandler = prevErrorHandler;
@@ -265,14 +250,10 @@ static int x11IOErrorHandler(Display *dpy)
     fprintf(stderr, "Nativewindow X11 IOError: Display %p (%s): %s\n", dpy, dpyName, errnoStr);
     fflush(stderr);
 
-    if( NULL != jvmHandle ) {
-        jniEnv = NativewindowCommon_GetJNIEnv(jvmHandle, jvmVersion, 0 /* asDaemon */, &shallBeDetached);
-        if (NULL != jniEnv) {
-            NativewindowCommon_FatalError(jniEnv, "Nativewindow X11 IOError: Display %p (%s): %s", dpy, dpyName, errnoStr);
-            if (shallBeDetached) {
-                (*jvmHandle)->DetachCurrentThread(jvmHandle);
-            }
-        }
+    jniEnv = NativewindowCommon_GetJNIEnv(0 /* asDaemon */, &shallBeDetached);
+    if (NULL != jniEnv) {
+        NativewindowCommon_FatalError(jniEnv, "Nativewindow X11 IOError: Display %p (%s): %s", dpy, dpyName, errnoStr);
+        NativewindowCommon_ReleaseJNIEnv(shallBeDetached);
     }
     if(NULL!=origIOErrorHandler) {
         origIOErrorHandler(dpy);
@@ -283,7 +264,6 @@ static int x11IOErrorHandler(Display *dpy)
 static void x11IOErrorHandlerEnable(int onoff, JNIEnv * env) {
     if(onoff) {
         if(NULL==origIOErrorHandler) {
-            setupJVMVars(env);
             origIOErrorHandler = XSetIOErrorHandler(x11IOErrorHandler);
         }
     } else {