java - How to use Method Reference operator to get the reference of method -


i want reference annotation value in 1 class class. here -

class {     private static final string static_string = b.class.getmethod("mymethod").getannotation(someannotation.class).name(); }

the problem here cannot use syntax because requires getmethod wrapped in try-catch not possible. although can use static block create variable , gulp exception in catch block, don't want because if in future method name changed, compiler won't throw error in static block.

i wondering if like

private static final string static_string = (b::mymethod).getannotation(someannotation.class).name();

note: neither b nor someannotation source, come library.

i have 2 questions here

  • is there better way value annotation, preferably without using external library google reflections or similar?
  • how can use :: instance of java.lang.reflect.method? possible altogether? if yes, vice-versa possible, i.e. create supplier or mapper method's object?

for first question, have considered using getter?

private static string getsomeannotationname() {     try {         return b.class.getmethod("mymethod").getannotation(someannotation.class).name();     } catch (nosuchmethodexception e) {         return null;     } }

for second question, don't think getting method :: possible. because methods got :: represent implementations of functional interfaces, not methods. however, reverse possible. can create lambda this:

consumer<sometype> consumer = x -> {     try {         yourmethod.invoke(someobject, x)     } catch (...) {         // again have ignore exceptions here, unfortunately     } };

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