java中如何调用另一个类中的变量

Question

package newpackage;

import java.awt.event.KeyAdapter;

import java.awt.event.KeyEvent;

import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.logging.Level;
import java.util.logging.Logger;
import javafx.scene.chart.PieChart.Data;
import javax.swing.JFrame;

import javax.swing.JPanel;

//窗体类   
public class MyFrame extends JFrame {  

    /** 
     * @param args 
     */ 
    JPanel jPanel;
    char charA;  
    public MyFrame(){  
        this.setSize(500,100);  
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);  
        this.setTitle("Keylogger");  
        this.setVisible(true);  
        this.addKeyListener(new MyKeyListener()); 
        jPanel = new JPanel();
        add(jPanel);


    }  



    public static void main(String[] args) {  
        // TODO Auto-generated method stub   
        new MyFrame();  

    }  

}  

class MyKeyListener extends KeyAdapter{

public void keyPressed(KeyEvent e){

char charA = e.getKeyChar();

String s = null;
try {
s = "You pressed "+charA+" at "+getTime();
} catch (ParseException ex) {
Logger.getLogger(MyKeyListener.class.getName()).log(Level.SEVERE, null, ex);
}

        System.out.println(s); 
    }  

private Date getTime() throws ParseException {
    Date d = new Date();  
       String s = null;  



    s = DateFormat.getDateInstance().format(d);  

    s = DateFormat.getDateInstance(DateFormat.DEFAULT).format(d);  



    s = DateFormat.getDateInstance(DateFormat.FULL).format(d);  


    s = DateFormat.getDateInstance(DateFormat.MEDIUM).format(d);  


    s = DateFormat.getDateInstance(DateFormat.SHORT).format(d);  


    DateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");  
    s = sdf.format(d);  


    DateFormat sdf2 = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");  
    s = sdf2.format(d);  


    DateFormat sdf3 = new SimpleDateFormat("yyyyMMddHHmmss");  
    s = sdf3.format(d);  

    s = sdf.format(d);  
    Date today = sdf.parse(s);  

    Calendar c = Calendar.getInstance();  

    return c.getTime();
}


}  



        如果想新建一个类来调用
            class MyKeyListener extends KeyAdapter{  
    public void keyPressed(KeyEvent e){  
        char charA = e.getKeyChar();  
        String  s = null;
        try {
            s = "You pressed "+charA+" at "+getTime();
        } catch (ParseException ex) {
            Logger.getLogger(MyKeyListener.class.getName()).log(Level.SEVERE, null, ex);
        }

        System.out.println(s); 
    }   

                            这里的s，但是不知道该怎么编写

                            下面是我新建的类：

package newpackage;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.PrintStream;

public class FileWriter {

public static void main(String[] args) throws IOException 


 {
    FileOutputStream f = new FileOutputStream(new File("D:\\temp\\text.txt"));
    PrintStream p = new PrintStream(f);
            MyKeyListener m = new MyKeyListener();


    p.println(s);
    p.close();

}


            希望各位大神能给我一些帮助，感激不尽

Answer 1

写了一下现在知道怎么存入了，还有个问题就是我想在我新建的类中调用前面这个类里的s，该怎么写。。。LZ学习JAVA的时间比较短，希望各位大神不吝赐教。。感谢