private interface Int1 {}
protected interface Int2 {}

public interface TestInterfaceModifiers {
    private interface Int1 {}
    protected interface Int2 {}
}

/*
    Produces the following errors:
D:\Java\jeg\lang>javac TestInterfaceModifiers.java
TestInterfaceModifiers.java:1: modifier private not allowed here
private interface Int1 {}
        ^
TestInterfaceModifiers.java:2: modifier protected not allowed here
protected interface Int2 {}
          ^
TestInterfaceModifiers.java:5: illegal combination of modifiers: public
and private
    private interface Int1 {}
            ^
TestInterfaceModifiers.java:6: illegal combination of modifiers: public
and protected
    protected interface Int2 {}

 */