Generic Method Type Safety

public abstract class AbstractNodeType {
  // ..

  public abstract <T extends AbstractNode> T createInstance();
}

public class ThingType {
  // ..

  public Thing createInstance() {
    return new Thing(/* .. */);
  }
}

// FYI
public class Thing extends AbstractNode { /* .. */ }

interface Node{
}
interface NodeType<T extends Node>{
	T createInstance();
}
class Thing implements Node{}
class ThingType implements NodeType<Thing>{
	public Thing createInstance() {
		return new Thing();
	}
}
class UberThing extends Thing{}
class UberThingType extends ThingType{
	@Override
	public UberThing createInstance() {
		return new UberThing();
	}
}

public abstract class AbstractNodeType<T extends AbstractNode> {
  public abstract T createInstance();
}
public class ThingType<Thing> {
  public Thing createInstance() {
    return new Thing(...);
  }
}