格林模拟试题一（下）(3)

  question 37)

given the following code

import java.awt.*;
public static void main(string argv){
s.setsize(300,200);
}

}

how could you set the frame surface color to pink

1)s.setbackground(color.pink); 
3)s.background(pink); 

question 38)
how can you change the current working directory using an instance of the file class called filename? 
1) filename.chdir("dirname") 
2) filename.cd("dirname") 
3) filename.cwd("dirname") 
4) the file class does not support directly changing the current directory. question 39)

if you create a textfield  with a constructor to set it to occupy 5 columns, what difference will it make if you use it with a proportional font (ie times roman) or a fixed pitch typewriter style font (courier).

1)with a fixed font you will see 5 characters, with a  proportional it will depend on the width of the characters 
4)both will show exactly 5 characters |||

question 40)
given the following code how could you invoke the base constructor that will print out the string "base constructor";

class base{
system.out.println("base constructor");
base(){
}

public class sup extends base{
sup s= new sup();
}
{
}

public void derived()
//three
}

 

1) on the line after //one put base(10); 
3) on the line after //two put super(10);