2日間JAVA知識まとめ

6919 ワード

           JAVA  ,             ,          ,          。
 
   
1.JAVA       ,          ,                    , C++        。

2.Unicode

3. : 0 , 013,029
: 0x 0X , 0xA3,0X1b

4. : + E +
15E4 = 15 * 10^4
26E-4 = 26 * 10^(-4)

5. : final float PI = 3.1415;
final public int MAX = 100;
        final “  ”   ,        ,      c++  const  

6. : ,
int c[][];
c = new[3][];
c[0] = new int[1];
c[1] = new int[3];
c[2] = new int[5];
length
:c.length :c[0].length

7. (static) : ,
Student s1;
Student.count s1.count

8.main() , ,

9. , , ,

interface inf{...}
class father implements inf{...}
class son extends father{...}
...main(...){
inf s1 = new inf();
inf s2 = new inf();
s1 = new father();
s2 = new son();
}

10. throws : , throws XXException

11. :
System.in
BufferedReader , System.in
InputStreamReader , BufferedReader System.in

InputStreamReader iin = new InputStreamReader(System.in);
BufferedReader bin = new BufferedReader(iin);

12. AWT
Component plain
Container boln
Window italic
Panel
Frame
Dialog

13. AWT
(Button ):
Class Myclass extends Frame implements ActionListener{
static Myclass frm = new Myclass();
static Button btn1;
....
...main(...){
frm.setTitle("FrmName");
btn1 = new Button("ButtonName");
btn1.addActionListener(frm);//
frm.add(btn1);
frm.setvisible(true);
}
public void actionPerformed (ActionEvent e){
//
}
}

14. Swing
, ActionListen

:
......
......
gre = new JMenuItem("green");
gre.addActionListener(new Handler1());
lb1 = new JLabel("Menu Example");
......
class Handler1 implements ActionListener{
public void actionPerformed (ActionEvent e){
JMenuItem mi = (JMenuItem) e.getSource();
if(mi == gre)
lb1.setForgeground(color.green);
}
}

15. Applet
init,start,stop,destory,paint

16. :
   : Thread ,Runnable

Sleep(); ,

Synchronized : public synchronized static void Sub(int m)
     ,      Sub()   ,           Sub(),        Sub()   ,        Sub()