Simple of example of how to use injection with objects that require things which cannot always be injected.

Consumer.java

public class Consumer {
  @Inject ExampleClass.Factory exampleClassFactory;
  
  public void fireZeMissles() {
    ExampleClass ex = exampleClassFactory.createForUser(42);
    ex.doThings();
  }
}

ExampleClass.java

public class ExampleClass {
  private final int userId;
  private final FooBar fooBar;
  private final Gizmo gizmo;
  
  private ExampleClass(int userId, FooBar fooBar, Gizmo gizmo) {
    this.userId = userId;
    this.fooBar = fooBar;
    this.gizmo = gizmo;
  }
  
  public void doThings() {
    // ...
  }
  
  public static class Factory {
    private final FooBar fooBar;
    private final Gizmo gizmo;
    
    @Inject public Factory(FooBar fooBar, Gizmo gizmo) {
      this.fooBar = fooBar;
      this.gizmo = gizmo;
    }
    
    public ExampleClass createForUser(int userId) {
      return new ExampleClass(userId, fooBar, gizmo);
    }
  }
}