簡答應用題
1.下面程式執行後，可以使用上下左右鍵移動元件。 補充下畫線部分的程式碼。
import java.awt.*;
import java.awt.event.*;
public class E6 extends Frame implements keyListener
{
TextField b1;
int x,y;
E6()
{
setLayout (new FlowLayout());
b1 = new TextField("走");
__[1]__
b.addkeyListener(this);
setSize (200,120);
addWindowListener(new WindowListener()
{
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
});
}
public void keyPressed(KeyEvent e)
{
x=b1.getBouds().x;
y=b1.getBouds().y;
if(e.getKeyCode()==__[2]__)
{
y=y-3;
if(y<=1)y=50;
b1.setLocation(x,y);
}
if(e.getkeyCode()==keyEven.VK_DOWN)
{
y=y+3;
if(y>=100)y=50;
b1.setLocation(x,y);
}
if(e.getkeyCode()==keyEvent.VK_LEFT)
{
x=x-3;
if(x<=1)x=50;
__[3]__;
}
if(e.getkeyCode()==keyEvent.VK_RIGHT)
{
x=x+3;
if(x>=100)x=50;
b1.setLocation(x,y);
}
}
public void keyTyped(KeyEvent e)
{}
public void keyReleased(KeyEvent e)
{}
public static void main (String args[])
{
E6 a = new E6();
__[4]__;
}
}
2.下面程式是從命令視窗介面輸入圓半徑，然後計算球圓面積與周長。把劃線部分填上語句，將程式補充完整。
import java.io.*;
public class Qiumianji
{
public static void main (String args[ ])
{
int a = 0;
double b,c;
Sting s;
try{
BufferedReader br =new BufferedReader (new InputStreamReader (___【1】__));
s = br.readLine();
a = __【2】__;
}
catch(IOExcepion e)
{}
b = 3.14*a*a;
c = 2*3.14*a;
System.out.println(”該圓面積為”+b+””+”周長為”+c);
}
}