Method signature is missing in the StackFrame API. This proposes to add
StackFrame::getMethodDescriptor method to return the method descriptor
in a stack frame.
Webrev at:
http://cr.openjdk.java.net/~mchung/jdk10/webrevs/8186050/webrev.00/index.html
There are a couple options how to present the method signature in the
API level:
1. Class<?>[] getParameterTypes() and Class<?> getReturnTypes() similiar
to what java.lang.reflect.Method has.
2. java.lang.invoke.MethodType
3. a String representation (i) comma-separated list of the method's
formal parameter types (ii) bytecode method descriptor as specified in JVMS
Returning Class<?> instance should require to add a new StackWalker
option to access to the parameter types and return type for option #1
and #2. StackFrame::getDeclaringClass requires the stack walker to have
the RETAIN_CLASS_REFERENCE capability.
Option #2 returning MethodType is handy while java.lang would reference
a type in java.lang.invoke.
Option #3 requires the caller to parse the return string and call
Class.forName to get the Class<?> instance. OTOH
MethodType::fromMethodDescriptorString​ method that returns MethodType
from a bytecode method descriptor string.
Method signature is for information for typical cases. Getting Class<?>
for the parameter types and return type would be a niche case. I think
returning the method descriptor string is a good option - keep the API
simple and can use MethodType::fromMethodDescriptorString​ to get back
the types if needed.
thanks
Mandy
