average.java

问题描述：本实验综合体现面向对象程序设计技术。此实验需应用面向对象程序设计课程中的“封装和继承”的基本原理

import  java.awt.* ;
import  java.awt.event.*;
import  javax.swing.*;
import  java.math.*;
import  java.util.*;
public class textave extends WindowAdapter implements TextListener
{
  Frame  f;
  TextArea    ta1;
  TextField   tf1,tf2;
  Label    l1,l2;
  String   s,sum1,aver1;
  double   sum;
  double   aver;

  public  void  display()
  {
    Panel   p2,p3 ;
    f=new  Frame("求平均数");
    f.setSize(300,200)         ;
    f.setLocation(100,100)     ;
    f.setBackground(Color.lightGray) ;
    f.setLayout(new GridLayout(3,1));
    p2 =new Panel();
    p2.setLayout(new GridLayout(1,2));
    p3 =new Panel();
    p3.setLayout(new GridLayout(1,2));
    l1=new  Label("和");
    l1.setSize(50,50);
    l2=new  Label("平均数");
    l2.setSize(50,50);
    ta1 =new TextArea("  ");
    tf1 =new TextField("  ");
    tf2 =new TextField("  ");
    ta1.addTextListener(this);
    f.add(ta1);
    f.add(p2);
    f.add(p3);
    p2.add(l1);
    p2.add(tf1);
    p3.add(l2);
    p3.add(tf2);
    f.addWindowListener(this);
    f.setVisible(true);
  }

  public  void  windowClosing(WindowEvent  e)
  {
    System.exit(0);
  }
  public  void  textValueChanged(TextEvent e)
  {
    if(e.getSource()==ta1)
    {
      s=ta1.getText();
      StringTokenizer  TT =new StringTokenizer(s);
      int n=TT.countTokens();
      String  a[]=new  String[n];
      for(int i=0;i<=n-1;i++)
      {
         sum=0;
         String  temp=TT.nextToken();
         a[i]=temp;
      }
      for(int i=0;i<=n-1;i++)
      {           
       sum=sum+Double.parseDouble(a[i]);
       aver=sum/n;
      }
     }
      sum1=String.valueOf(sum);
      aver1=String.valueOf(aver);


     tf1.setText(sum1);
     tf2.setText(aver1);


   
  }

  public  static  void  main(String  arg[])
  {
    (new  textave()).display();
  }

}