title: Why can't we autowire an abstract class inside a concrete class in Spring?
body: <pre><code>public abstract class A{
  
  }
  
  class B{
  
  @Autowired
  A a;
  
  }
  </code></pre>
  
  <p>Why doesn't this seem to work, when I can insert an interface into Spring ? Shouldn't it locate a concrete class that extends that abstract class A, and then wire it into the class B, like it does for interfaces ?</p>