title: Why don't Java wrapper classes have no-arg constructors?
body: <p>What is the rationale of not providing no-arg constructors in Wrapper Classes? I know that they were inherently built for Wrapping primitive types, so the right way is to provide a primitive type for constructors.</p>
  
  <p>However, considering primitive types have no-arg constructor, why don't they have one? </p>
  
  <p>Besides, if they had no-arg constructors, they could be instantiated as <code>T.class.newInstance()</code>. However, since <code>newInstance()</code> requires no-arg constructor, this won't work with Wrapper Classes.</p>