Method argument extends class implements interface

I have the following class and interface:

public class BasicObject{...}
public interface CodeObject{...}

I want to create a method in which the argument needs to be of type BasicObject and implements CodeObject. I tried the following code but it doesn't guarantee clazz to be a class that implements CodeObject.

myMethod(Class<? extends BasicObject> clazz){...}

I want to do something like this but it doesn't compile:

myMethod(Class<? extends BasicObject implements CodeObject> clazz){...}

Your pattern class has to extend BasicObject and extend/implement CodeObject (which is actually an interface). You can do it with multiple classes declared in the wildcard definition of the method signature, like this:

public <T extends BasicObject & CodeObject> void myMethod(Class<T> clazz)

Note that it won't work if you do it any of these ways:

public <T extends BasicObject, CodeObject> void myMethod(Class<T> clazz)

This is technically valid syntax, but CodeObject is unused; the method will accept any classes that extends BasicObject, no matter whether they extend/implement CodeObject.
public void myMethod(Class<? extends BasicObject & CodeObject> clazz)
public void myMethod(Class<? extends BasicObject, CodeObject> clazz)

These are just wrong syntax according to Java.

Here is an approach which is a bit verbose, but avoids generics headaches. Create another class which does the extending/implementing:

public abstract class BasicCodeObject 
    extends BasicObject 
    implements CodeObject {...}

Then your method can be:

public <T extends BasicCodeObject> void myMethod(Class<T> clazz) {...}

Method argument extends class implements interface

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