java - Interface implementation access modifier not as expected -

i came across example of interface implementation can't head around, text not having reasoning the answer on here can lend hand.

given interface

interface flyer{    void takeoff();    boolean land(); } 

then suppose have implementation follows

class aeroplane implements flyer{    public void takeoff(){    ...    }    //insert code here        return true;    }   } 

the code insert given public boolean land(){ , states following incorrect boolean land(){

why need have public when interface has defined method package-private, surely boolean land(){ should implement interface, or have missed something?

"the interface has defined method package-private"

all methods declared in interfaces public definition. there no way around this.

this

interface flyer{    void takeoff();    boolean land(); } 

is equivalent this

interface flyer{    public void takeoff();    public boolean land(); } 

this illegal:

interface flyer{    private void takeoff();    private boolean land(); } 

as this:

interface flyer{    protected void takeoff();    protected boolean land(); } 

neither compile.