title: Guice Inject Field in class not created by Guice
body: <p>I have a class like so, that I create myself somewhere in my code:</p>
  
  <pre><code>class StarryEyes {
     @Inject MyValidator validator;
  
     public StarryEyes(String name) {
        //..
     }
  
     public doSomething() {
        // validator is NULL
     }
  }
  </code></pre>
  
  <p>I want Guice to inject an instance of validator, which has a @Singleton annotation.
  I have a module that's loaded at startup and it contains the line:</p>
  
  <pre><code>bind(MyValidator.class);
  </code></pre>
  
  <p>However, it doesn't seem to work as "validator" is always null. I've tried a number of variations like:</p>
  
  <pre><code>bind(MyValidator.class)toInstance(new MyValidator());
  </code></pre>
  
  <p>or other things like that. Is this not how Guice is supposed to work?</p>