ruby - How can I tell if a method is read-write, read-only, or write-only, via introspection? -

i coming java, , want know if can 'set' instance variable object using introspection.

for example, if have following class declaration, 2 instance variables, first_attribute , second_attribute:

class someclass     attr_accessor :first_attribute   attr_reader :second_attribute    def initialize()       # ...   end end 

i want able instance methods, presumably calling someclass.instance_methods , know of instance methods read/write vs. read-only.

in java can by:

propertydescriptor[] properties = propertyutils.getpropertydescriptors(someclass); (prop : properties) {   if (prop.getwritemethod() != null) {     //  can set one!   } } 

how do in ruby?

there's not built-in java property stuff, can pretty this:

self.class.instance_methods.grep(/\w=$/) 

which return names of setter methods on class.