jobject EnumMapper::mapEnum(const char *clazzName, int index)
{
// The fact that we can even do this depends upon a couple of assumptions,
// mainly some knowledge about the orderin of the various constants in
// both the C and Java enums. Should those values ever change,
// the World Will End.
std::string methodSig("()[L");
methodSig.append(clazzName);
methodSig.append(";");
JNIEnv *env = JNIUtil::getEnv();
// Create a local frame for our references
env->PushLocalFrame(LOCAL_FRAME_SIZE);
if (JNIUtil::isJavaExceptionThrown())
return NULL;
jclass clazz = env->FindClass(clazzName);
if (JNIUtil::isJavaExceptionThrown())
POP_AND_RETURN_NULL;
jmethodID mid = env->GetStaticMethodID(clazz, "values", methodSig.c_str());
if (JNIUtil::isJavaExceptionThrown())
POP_AND_RETURN_NULL;
jobjectArray jvalues = (jobjectArray) env->CallStaticObjectMethod(clazz, mid);
if (JNIUtil::isJavaExceptionThrown())
POP_AND_RETURN_NULL;
jobject jthing = env->GetObjectArrayElement(jvalues, index);
if (JNIUtil::isJavaExceptionThrown())
POP_AND_RETURN_NULL;
return env->PopLocalFrame(jthing);
}
NS_IMETHODIMP
nsJavaXPTCStub::CallMethod(PRUint16 aMethodIndex,
const XPTMethodDescriptor *aMethodInfo,
nsXPTCMiniVariant *aParams)
{
#ifdef DEBUG_JAVAXPCOM
const char* ifaceName;
mIInfo->GetNameShared(&ifaceName);
LOG(("---> (Java) %s::%s()\n", ifaceName, aMethodInfo->name));
#endif
nsresult rv = NS_OK;
JNIEnv* env = GetJNIEnv();
jobject javaObject = env->CallObjectMethod(mJavaWeakRef, getReferentMID);
nsCAutoString methodSig("(");
// Create jvalue array to hold Java params
PRUint8 paramCount = aMethodInfo->num_args;
jvalue* java_params = nsnull;
const nsXPTParamInfo* retvalInfo = nsnull;
if (paramCount) {
java_params = new jvalue[paramCount];
if (!java_params)
return NS_ERROR_OUT_OF_MEMORY;
for (PRUint8 i = 0; i < paramCount && NS_SUCCEEDED(rv); i++)
{
const nsXPTParamInfo ¶mInfo = aMethodInfo->params[i];
if (!paramInfo.IsRetval()) {
rv = SetupJavaParams(paramInfo, aMethodInfo, aMethodIndex, aParams,
aParams[i], java_params[i], methodSig);
} else {
retvalInfo = ¶mInfo;
}
}
NS_ASSERTION(NS_SUCCEEDED(rv), "SetupJavaParams failed");
}
// Finish method signature
if (NS_SUCCEEDED(rv)) {
methodSig.Append(')');
if (retvalInfo) {
nsCAutoString retvalSig;
rv = GetRetvalSig(retvalInfo, aMethodInfo, aMethodIndex, aParams,
retvalSig);
methodSig.Append(retvalSig);
} else {
methodSig.Append('V');
}
NS_ASSERTION(NS_SUCCEEDED(rv), "GetRetvalSig failed");
}
// Get Java method to call
jmethodID mid = nsnull;
if (NS_SUCCEEDED(rv)) {
nsCAutoString methodName;
if (XPT_MD_IS_GETTER(aMethodInfo->flags) ||
XPT_MD_IS_SETTER(aMethodInfo->flags)) {
if (XPT_MD_IS_GETTER(aMethodInfo->flags))
methodName.AppendLiteral("get");
else
methodName.AppendLiteral("set");
methodName.AppendASCII(aMethodInfo->name);
methodName.SetCharAt(toupper(methodName[3]), 3);
} else {
methodName.AppendASCII(aMethodInfo->name);
methodName.SetCharAt(tolower(methodName[0]), 0);
}
// If it's a Java keyword, then prepend an underscore
if (gJavaKeywords->GetEntry(methodName.get())) {
methodName.Insert('_', 0);
}
jclass clazz = env->GetObjectClass(javaObject);
if (clazz)
mid = env->GetMethodID(clazz, methodName.get(), methodSig.get());
NS_ASSERTION(mid, "Failed to get requested method for Java object");
if (!mid)
rv = NS_ERROR_FAILURE;
}
// Call method
jvalue retval;
if (NS_SUCCEEDED(rv)) {
if (!retvalInfo) {
env->CallVoidMethodA(javaObject, mid, java_params);
} else {
switch (retvalInfo->GetType().TagPart())
{
case nsXPTType::T_I8:
retval.b = env->CallByteMethodA(javaObject, mid, java_params);
break;
case nsXPTType::T_I16:
case nsXPTType::T_U8:
retval.s = env->CallShortMethodA(javaObject, mid, java_params);
break;
case nsXPTType::T_I32:
case nsXPTType::T_U16:
retval.i = env->CallIntMethodA(javaObject, mid, java_params);
break;
case nsXPTType::T_I64:
case nsXPTType::T_U32:
retval.j = env->CallLongMethodA(javaObject, mid, java_params);
break;
case nsXPTType::T_FLOAT:
retval.f = env->CallFloatMethodA(javaObject, mid, java_params);
break;
case nsXPTType::T_U64:
case nsXPTType::T_DOUBLE:
retval.d = env->CallDoubleMethodA(javaObject, mid, java_params);
break;
case nsXPTType::T_BOOL:
retval.z = env->CallBooleanMethodA(javaObject, mid, java_params);
break;
case nsXPTType::T_CHAR:
case nsXPTType::T_WCHAR:
retval.c = env->CallCharMethodA(javaObject, mid, java_params);
break;
case nsXPTType::T_CHAR_STR:
case nsXPTType::T_WCHAR_STR:
case nsXPTType::T_IID:
case nsXPTType::T_ASTRING:
case nsXPTType::T_DOMSTRING:
case nsXPTType::T_UTF8STRING:
case nsXPTType::T_CSTRING:
case nsXPTType::T_INTERFACE:
case nsXPTType::T_INTERFACE_IS:
retval.l = env->CallObjectMethodA(javaObject, mid, java_params);
break;
case nsXPTType::T_VOID:
retval.j = env->CallLongMethodA(javaObject, mid, java_params);
break;
default:
NS_WARNING("Unhandled retval type");
break;
}
}
// Check for exception from called Java function
jthrowable exp = env->ExceptionOccurred();
if (exp) {
// If the exception is an instance of XPCOMException, then get the
// nsresult from the exception instance. Else, default to
// NS_ERROR_FAILURE.
if (env->IsInstanceOf(exp, xpcomExceptionClass)) {
jfieldID fid;
fid = env->GetFieldID(xpcomExceptionClass, "errorcode", "J");
if (fid) {
rv = env->GetLongField(exp, fid);
} else {
rv = NS_ERROR_FAILURE;
}
NS_ASSERTION(fid, "Couldn't get 'errorcode' field of XPCOMException");
} else {
rv = NS_ERROR_FAILURE;
}
}
}
// Handle any 'inout', 'out' and 'retval' params
if (NS_SUCCEEDED(rv)) {
for (PRUint8 i = 0; i < paramCount; i++)
{
const nsXPTParamInfo ¶mInfo = aMethodInfo->params[i];
if (paramInfo.IsIn() && !paramInfo.IsOut() && !paramInfo.IsDipper()) // 'in'
continue;
// If param is null, then caller is not expecting an output value.
if (aParams[i].val.p == nsnull)
continue;
if (!paramInfo.IsRetval()) {
rv = FinalizeJavaParams(paramInfo, aMethodInfo, aMethodIndex, aParams,
aParams[i], java_params[i]);
} else {
rv = FinalizeJavaParams(paramInfo, aMethodInfo, aMethodIndex, aParams,
aParams[i], retval);
}
}
NS_ASSERTION(NS_SUCCEEDED(rv), "FinalizeJavaParams/SetXPCOMRetval failed");
}
if (java_params)
delete [] java_params;
#ifdef DEBUG
if (env->ExceptionCheck())
env->ExceptionDescribe();
#endif
env->ExceptionClear();
LOG(("<--- (Java) %s::%s()\n", ifaceName, aMethodInfo->name));
return rv;
}
void
ThrowException(JNIEnv* env, const nsresult aErrorCode, const char* aMessage)
{
// Only throw this exception if one hasn't already been thrown, so we don't
// mask a previous exception/error.
if (env->ExceptionCheck())
return;
// If the error code we get is for an Out Of Memory error, try to throw an
// OutOfMemoryError. The JVM may have enough memory to create this error.
if (aErrorCode == NS_ERROR_OUT_OF_MEMORY) {
jclass clazz = env->FindClass("java/lang/OutOfMemoryError");
if (clazz) {
env->ThrowNew(clazz, aMessage);
}
env->DeleteLocalRef(clazz);
return;
}
// If the error was not handled above, then create an XPCOMException with the
// given error code and message.
// Create parameters and method signature. Max of 2 params. The error code
// comes before the message string.
PRInt64 errorCode = aErrorCode ? aErrorCode : NS_ERROR_FAILURE;
nsCAutoString methodSig("(J");
jstring message = nsnull;
if (aMessage) {
message = env->NewStringUTF(aMessage);
if (!message) {
return;
}
methodSig.AppendLiteral("Ljava/lang/String;");
}
methodSig.AppendLiteral(")V");
// In some instances (such as in shutdownXPCOM() and termEmbedding()), we
// will need to throw an exception when JavaXPCOM has already been
// terminated. In such a case, 'xpcomExceptionClass' will be null. So we
// reset it temporarily in order to throw the appropriate exception.
if (xpcomExceptionClass == nsnull) {
xpcomExceptionClass = env->FindClass("org/mozilla/xpcom/XPCOMException");
if (!xpcomExceptionClass) {
return;
}
}
// create exception object
jthrowable throwObj = nsnull;
jmethodID mid = env->GetMethodID(xpcomExceptionClass, "<init>",
methodSig.get());
if (mid) {
throwObj = (jthrowable) env->NewObject(xpcomExceptionClass, mid, errorCode,
message);
}
NS_ASSERTION(throwObj, "Failed to create XPCOMException object");
// throw exception
if (throwObj) {
env->Throw(throwObj);
}
}
