averagerainfallapp.java

还不错的java基本实例

package ch4;
import javax.swing.*;
public class AverageRainfallApp {
    double[] rainfall;
    double[] differece  = new double[12] ;

     public AverageRainfallApp() {
         rainfall =new double[12];
     for(int i=0;i<12;i++)  {
        rainfall[i] =Double.parseDouble(JOptionPane.showInputDialog(
                "请输入" + (i+1)  + "月降雨量的值" ));
        }
     }

   public double AnnualAverageRainfall() {
       double sum=0;
       for(int i=0;i<12;i++) {
           sum+=rainfall[i];
       }
       return sum/12;
    }

    public void computeDifferece(){
       for(int i=0;i<12;i++) {
           differece[i] = rainfall[i] - AnnualAverageRainfall();
       }
    }

    public void printArray(double[] aArray) {
         String output="";
         aArray[1]=20;
        // aArray= new double[]{1,2,3,4,5};
        // aArray[1]=16;

        for( int i=0;i<aArray.length;i++){
           output+=String.valueOf( aArray[i])+"\n";
        }
        JOptionPane.showMessageDialog( null,output);    
    }

    public static void main( String[] args) {
        AverageRainfallApp app=new AverageRainfallApp();
        app.printArray(app.rainfall);
        app.computeDifferece();
        app.printArray(app.differece);

        String output = "月平均降雨量: "+ app.AnnualAverageRainfall()+"mm"+"\n\n";
        output+="月"+"\t"+ "月降雨量"+"\t"+ "月降雨量与月平均降雨量的偏差"+"\n";
      for( int i=0;i<12;i++){
          output+=(i+1)+"\t"+String.valueOf(app.rainfall[i])+
                  "\t"+String.valueOf(app.differece[i])+"\n";
       }
         JTextArea text1=new JTextArea(15,30);
         text1.setText(output);
    JOptionPane.showMessageDialog( null,text1 ,
              "结果", JOptionPane.PLAIN_MESSAGE );
    }
}