JAVA中,下面一段代码怎么改才能读出文档中的5行数据而不是只有1行呢?

图片说明

 import java.awt.*;
import java.awt.event.*;
import java.awt.Color.*;
import java.io.*;

class FileStream extends Frame implements ActionListener
{
    TextArea ta=new TextArea("",10,30);
    Button b=new Button("读取数据");


    FileStream()
    {

        this.add(ta,"North");
        this.add(b,"South");


        b.addActionListener(this);

        this.pack();
        this.setVisible(true);
    }



    File file;
    FileInputStream finStream;
    BufferedReader br;
    public void actionPerformed(ActionEvent e)
    {

        try
        {
            file=new File("E:\\test.txt");
            finStream=new FileInputStream(file);
            br=new BufferedReader(new InputStreamReader(finStream));
            String strText=br.readLine();


            while(br.readLine()!=null)
            {
                strText=br.readLine()+"\n";
            }

            ta.setText(strText);
        }
        catch(Exception ee){}
    }


    public static void main(String[] args)
    {
        new FileStream();
    }
}

原代码逻辑如下:

            while(br.readLine()!=null) //读一行
            {
                strText=br.readLine()+"\n"; //读下一行到strText中
            }

            ta.setText(strText);   //最后循环结束后strText值为null,和期望值不同

修改为:



      file = new File("d:\\test.txt");
            finStream = new FileInputStream(file);
            br = new BufferedReader(new InputStreamReader(finStream));
            String strResult = ""; 
            String strText;
            while ((strText = br.readLine()) != null) {

                strResult += strText + '\n';
             }       
            ta.setText(strResult);

测试结果如下图:

图片说明

用心回答每个问题,如果有帮助,请及时采纳答案好吗,非常感谢~~~

while(br.readLine()!=null)
{
strText=br.readLine()+"\n";
}
->
while((strText += br.readLine())!=null);