/*
* 在指定的接口和它的父接口中查找方法 ，如果方法没有找到则返回NULL (没有找到也不会抛出一个异常)
*
*
*/
Method* dvmFindInterfaceMethodHier(const ClassObject* iface,
const char* methodName, const DexProto* proto)
{
Method* resMethod = dvmFindVirtualMethod(iface, methodName, proto);
if (resMethod == NULL) {
/* scan superinterfaces and superclass interfaces */
int i;
for (i = 0; i < iface->iftableCount; i++) {
resMethod = dvmFindVirtualMethod(iface->iftable[i].clazz,
methodName, proto);
if (resMethod != NULL)
break;
}
}
return resMethod;
}
/*
* Resolve an interface method reference.
*
* Returns NULL with an exception raised on failure.
*/
Method* dvmResolveInterfaceMethod(const ClassObject* referrer, u4 methodIdx)
{
DvmDex* pDvmDex = referrer->pDvmDex;
ClassObject* resClass;
const DexMethodId* pMethodId;
Method* resMethod;
int i;
LOGVV("--- resolving interface method %d (referrer=%s)\n",
methodIdx, referrer->descriptor);
pMethodId = dexGetMethodId(pDvmDex->pDexFile, methodIdx);
resClass = dvmResolveClass(referrer, pMethodId->classIdx, false);
if (resClass == NULL) {
/* can't find the class that the method is a part of */
assert(dvmCheckException(dvmThreadSelf()));
return NULL;
}
if (!dvmIsInterfaceClass(resClass)) {
/* whoops */
dvmThrowExceptionWithClassMessage(
"Ljava/lang/IncompatibleClassChangeError;",
resClass->descriptor);
return NULL;
}
/*
* This is the first time the method has been resolved. Set it in our
* resolved-method structure. It always resolves to the same thing,
* so looking it up and storing it doesn't create a race condition.
*
* If we scan into the interface's superclass -- which is always
* java/lang/Object -- we will catch things like:
* interface I ...
* I myobj = (something that implements I)
* myobj.hashCode()
* However, the Method->methodIndex will be an offset into clazz->vtable,
* rather than an offset into clazz->iftable. The invoke-interface
* code can test to see if the method returned is abstract or concrete,
* and use methodIndex accordingly. I'm not doing this yet because
* (a) we waste time in an unusual case, and (b) we're probably going
* to fix it in the DEX optimizer.
*
* We do need to scan the superinterfaces, in case we're invoking a
* superinterface method on an interface reference. The class in the
* DexTypeId is for the static type of the object, not the class in
* which the method is first defined. We have the full, flattened
* list in "iftable".
*/
const char* methodName =
dexStringById(pDvmDex->pDexFile, pMethodId->nameIdx);
DexProto proto;
dexProtoSetFromMethodId(&proto, pDvmDex->pDexFile, pMethodId);
LOGVV("+++ looking for '%s' '%s' in resClass='%s'\n",
methodName, methodSig, resClass->descriptor);
resMethod = dvmFindVirtualMethod(resClass, methodName, &proto);
if (resMethod == NULL) {
LOGVV("+++ did not resolve immediately\n");
for (i = 0; i < resClass->iftableCount; i++) {
resMethod = dvmFindVirtualMethod(resClass->iftable[i].clazz,
methodName, &proto);
if (resMethod != NULL)
break;
}
if (resMethod == NULL) {
dvmThrowException("Ljava/lang/NoSuchMethodError;", methodName);
return NULL;
}
} else {
LOGVV("+++ resolved immediately: %s (%s %d)\n", resMethod->name,
resMethod->clazz->descriptor, (u4) resMethod->methodIndex);
}
LOGVV("--- found interface method %d (%s.%s)\n",
methodIdx, resClass->descriptor, resMethod->name);
/* we're expecting this to be abstract */
assert(dvmIsAbstractMethod(resMethod));
/* interface methods are always public; no need to check access */
/*
* The interface class *may* be initialized. According to VM spec
* v2 2.17.4, the interfaces a class refers to "need not" be initialized
* when the class is initialized.
*
* It isn't necessary for an interface class to be initialized before
* we resolve methods on that interface.
*
* We choose not to do the initialization now.
*/
//assert(dvmIsClassInitialized(resMethod->clazz));
/*
* The class is initialized, the method has been found. Add a pointer
* to our data structure so we don't have to jump through the hoops again.
*/
dvmDexSetResolvedMethod(pDvmDex, methodIdx, resMethod);
return resMethod;
}
