[JAVA] [Ruby] Does self refer to a class or an instance?


self can point to both a class and an instance.


For me, the image that points to an instance was stronger, but I recently learned that it points to a class, so I summarized it. I've heard that "ruby is the same as this in java", but I still don't know if it's exactly the same. I forgot this in Java now.


class ClassA
  def foo       #Instance method
    puts "ins_foo"
    puts self #This self is an instance(Instance of ClassA)Point to

  def self.foo  #Class method(This self is the class itself(ClassA)Point to)
    puts "self_foo"
    puts self #This self is the class itself(ClassA)Point to
# self_foo
# ClassA #Pointing to a class
# ins_foo
# #<ClassA:0x00007f93108144d0> #Pointing to an instance

I've read that when defining a class method, add self., but that self refers to the class.

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