ed.java

介绍有关java的资料 课件 相当一本书籍 里面都是很基础的知识

import java.awt.*;
import java.applet.*;

class MyE extends Exception{ // class MyException
  private int detailA,detailB;
  MyE(int a,int b){
  detailA = a;
  detailB = b;
  }
  public String toString(){
    return "MyException : "+detailA+"<"+detailB;
  }
}
class Cons{ // 设 置 一 个 常 数 ， 让 它 代 表 两 条 线 之 间 的 距 离
  final int jmp = 13;
}
public class ED extends Applet{ // class Exception Demo
  static void compare(int a,int b,Graphics g,int Ln,int col) throws MyE {
  Cons jump = new Cons();
  g.drawString("***************************",col,Ln);
  g.drawString("call compare("+a+","+b+")",col,Ln+jump.jmp);
  if (a<b)
    throw new MyE(a,b);
    g.drawString("normal exit :"+a+"> = "+b,col,Ln+2*jump.jmp);
  }
  static void callcompare(int a,int b,Graphics g,int Ln,int col){
    Cons jump = new Cons();
    try{
      compare(a,b,g,Ln,col);
    }
    catch(MyE e){
      g.drawString("Catch "+e,col,Ln+2*jump.jmp);
    }
    finally{
      g.drawString("return from callcompare()",col,Ln+3*jump.jmp);
    }
  }
  public void paint (Graphics g){
  Cons jump = new Cons();
  int Ln;
  int col;
  Ln = 10; col = 20;
  callcompare(10,5,g,Ln,col);
  Ln = Ln+5*jump.jmp;
  callcompare(5,5,g,Ln,col);
  Ln = Ln+5*jump.jmp;
  callcompare(5,10,g,Ln,col);
  }
}