How can I require a method argument in Java to implement multiple interfaces?

Question

It\'s legal to do this in Java:

 void spew(Appendable x)
 {
     x.append(\"Bleah!\\n\");
 }

How can I do this (syntax not legal):

Answer 1

You could do it with generics:

public <T extends Appendable & Closeable> void spew(T t){
    t.append("Bleah!\n");
    if (timeToClose())
        t.close();
}

Your syntax was almost right, actually.