title: ParametersAreNonnullByDefault javax annotation on class not doing null checks
body: <p>I have a class which is annotated with <code>ParametersAreNonnullByDefault</code> javax annotation. But its constructor and methods accept null parameters and don't throw <code>NullPointerException</code>.</p>
  
  <pre><code>@ParametersAreNonnullByDefault
  class MyClass {
      private Integer intField;
  
      public MyClass(Integer intField) {
          this.intField = intField;
      }
  
      public Integer someMethod(Integer a) {
          return a;
      }
  }
  </code></pre>
  
  <p>The following lines of code do not throw NullPointerException as I would expect:</p>
  
  <pre><code>MyClass obj = new MyClass(null);
  obj.someMethod(null);
  </code></pre>
  
  <p>As per the documentation, "This annotation can be applied to a package, class or method to indicate that the method parameters in that element are nonnull by default". Where/when is the null check being made for method parameters with this annotation?</p>