JVM Crashs when calling method a 2nd time
Hi Forum,
i have a urgent problem. I call java methods from my c++ code. This works fine if i call the methods only one time. If i try to call the method the second time. I got an execption and the jvm crashes. Here is my c++ code
void GDPNativeOpposite::Init(IN CString pluginPath){
CreateJVM(pluginPath);
m_clazz = m_env->FindClass("com/xxxx/geodatainterface/GeoDataInterface");
ExceptionProver();
m_bitmapMID = m_env->GetMethodID(m_clazz,"getBitmap","(DDDDDDDD)[B");
ExceptionProver();
m_bitmapSizeMID = m_env->GetMethodID(m_clazz,"getBitmapSize","()I");
ExceptionProver();
m_screenSizeMID = m_env->GetMethodID(m_clazz,"changeScreenSize","(II)V");
ExceptionProver();
m_coordInfoPopupMID = m_env->GetMethodID(m_clazz,"getCoordinateInfo","(DD)V");
}
void GDPNativeOpposite::CreateJVM(IN CString pluginPath){
JavaVMInitArgs args;
JavaVMOption cp[3];
HINSTANCE jvmDll= (HINSTANCE)NULL;
jint ( JNICALL *JNI_CreateJavaVM)(JavaVM **pm_vm,void **pm_env,void *args);
// change the current directory to the path of the dll,
// that we can load the dll and all depended dlls
// 1st store the old path
char szOldPath[1024];
GetCurrentDirectory(sizeof(szOldPath), szOldPath);
BOOL fOK = SetCurrentDirectory("C:/Programme/Java/jdk1.5.0_07/jre/bin/client");
//BOOL fOK = SetCurrentDirectory("C:/Programme/Java/jre1.5.0_06/bin/client");
//Load jar files
CString classPath ="";
CreateClassPath(pluginPath, classPath);
cp[0].optionString = classPath.GetBuffer(classPath.GetLength()-1);
classPath.ReleaseBuffer();
cp[1].optionString ="-verbose:jni";
cp[2].optionString ="-Xcheck:jni";
args.version = JNI_VERSION_1_2;//Version
args.nOptions = 2;
args.options = cp;
args.ignoreUnrecognized = TRUE;//Sometimes usefull
jvmDll = LoadLibrary("jvm.dll");//VM library
if( jvmDll == NULL )
{
MessageBox(NULL,"Problem loading VM library","JVM creation error", MB_OK);
}
// Get the .DLL function address of JNI_CreateJavaVM
JNI_CreateJavaVM = (jint (JNICALL *)(JavaVM **,void **, void* ) ) GetProcAddress( jvmDll,"JNI_CreateJavaVM" );
if( !JNI_CreateJavaVM )
{
MessageBox(NULL,"Could not find the JNI_CreateJavaVM function in the specified .DLL","JVM creation error", MB_OK);
}
// Create the VM
jint res = JNI_CreateJavaVM( &m_jvm, (void**) &m_env, &args );
SetCurrentDirectory(szOldPath);
DWORD dwLastErr = GetLastError();
if( res < 0 )
{
MessageBox(NULL,"Could not instantiate the JVM.","JVM creation error", MB_OK);
}
}
void GDPNativeOpposite::CreateClassPath(IN CString pluginPath, OUT CString &csClassPath){
//Some code
}
void GDPNativeOpposite::RecursiveJARSearch(IN CString root, OUT CString &classPath){
//Some code
}
void GDPNativeOpposite::StartJavaOpposite(INlong left, INlong top, INlong right, INlong bottom){
//Create a new instance of the GeoDataInterface class. <init> is constructor call.
jmethodID constrID = m_env->GetMethodID(m_clazz,"<init>","(II)V");
ExceptionProver();
m_instance = m_env->NewObject(m_clazz, constrID, (right-left), (bottom-top));
ExceptionProver();
}
long GDPNativeOpposite::GetBitmap(IN GEODECCOORD ltCoord, IN GEODECCOORD rbCoord, OUT GEOMEMBITMAP* &pBitmap){
JNIEnv* env;
if(m_jvm->AttachCurrentThread((void**)&env, NULL) < 0){
return 0;
}
m_jBitmap = 0L;
ExceptionProver();
m_jBitmap = (jbyteArray)env->CallObjectMethod(m_instance, m_bitmapMID, ltCoord.x, ltCoord.y, rbCoord.x, rbCoord.y, 0, 0, 0, 0);
ExceptionProver();
jsize bitmapSize = m_env->CallIntMethod(m_instance, m_bitmapSizeMID);
pBitmap = (GEOMEMBITMAP*)newbyte[sizeof(GEOMEMBITMAPINFO)+bitmapSize];
m_env->GetByteArrayRegion(m_jBitmap, 14, bitmapSize-14, (jbyte*)pBitmap->gmBitmap);//We don't need the BitmapFILEHeader!!!! So start from offset +14
ExceptionProver();
m_env->ReleaseByteArrayElements(m_jBitmap, m_env->GetByteArrayElements(m_jBitmap, 0), 0);
ExceptionProver();
pBitmap->gmInfo.giLoadBitmapFromDisk = 0;
pBitmap->gmInfo.giApplyPerPixelAlpha = 0;
pBitmap->gmInfo.giApplyReprojection = 0;
pBitmap->gmInfo.giInterpolMethod = imNEARESTNEIGHBOUR;
pBitmap->gmInfo.giMakeTransparentForObjects = 1;
pBitmap->gmInfo.giOriginalProjection = opREAL;
pBitmap->gmInfo.giTransformMethod = tmPRECISE;
return bitmapSize;
}
int GDPNativeOpposite::ExceptionProver(){
//Some code
}
This is the order i call the c++-functions:
Init(path);
StartGDPJavaOpposite(left, top, right, bottom);
GetBitmap(lCoord, rCoord, pBitmap);
GetBitmap(lCoord, rCoord, pBitmap); <-- Crashes here in (jbytearray)env->CallObjectMethod(...)
The global variables are defined in the header:
JNIEnv*m_env;// Declare JNIEnv variable
JavaVM *m_jvm;// Declare virtual machine variable
jobjectm_instance;//Instance of main class (com.xxxx.geodatainterface.GeoDataInterface)
jclassm_clazz;//Pointer to the class (com.xxxx.geodatainterface.GeoDataInterface)
jmethodIDm_bitmapMID;//MethodID of the getBitmap java method
jmethodIDm_screenSizeMID;//MethodID of the proper java method
jmethodIDm_bitmapSizeMID;//MethodID of the proper java method
jmethodIDm_coordInfoPopupMID;//MethodID of the proper java method
jmethodIDm_destroyCoreMID;//MethodID of the proper java method
jbyteArraym_jBitmap;
Message was edited by:
OliverSchwarz
