jjava文件读取

  1 package textopen;
  2 
  3 import java.awt.BorderLayout;
  4 import java.awt.EventQueue;
  5 import java.awt.event.ActionEvent;
  6 import java.awt.event.ActionListener;
  7 import java.io.File;
  8 import java.io.FileInputStream;
  9 import java.io.FileNotFoundException;
 10 import java.io.IOException;
 11 
 12 import javax.swing.JFrame;
 13 import javax.swing.JPanel;
 14 import javax.swing.border.EmptyBorder;
 15 import javax.swing.JButton;
 16 import java.awt.CardLayout;
 17 import javax.swing.JTextField;
 18 import javax.swing.JScrollPane;
 19 import javax.swing.JTextArea;
 20 import java.awt.GridLayout;
 21 
 22 public class textopen1 extends JFrame implements ActionListener{
 23 
 24     private JPanel contentPane;
 25     private JButton openButton;
 26     private JPanel panel;
 27     private Object i;
 28     private JScrollPane scrollPane;
 29     private JPanel panel_1;
 30     private JTextArea text;
 31 
 32     /**
 33      * Launch the application.
 34      */
 35     public static void main(String[] args) {
 36         EventQueue.invokeLater(new Runnable() {
 37             public void run() {
 38                 try {
 39                     textopen1 frame = new textopen1();
 40                     frame.setVisible(true);
 41                 } catch (Exception e) {
 42                     e.printStackTrace();
 43                 }
 44             }
 45         });
 46     }
 47 
 48     /**
 49      * Create the frame.
 50      */
 51     public textopen1() {
 52         setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 53         setBounds(100, 100, 595, 523);
 54         contentPane = new JPanel();
 55         contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
 56         contentPane.setLayout(new BorderLayout(0, 0));
 57         setContentPane(contentPane);
 58         
 59         panel = new JPanel();
 60         contentPane.add(panel, BorderLayout.SOUTH);
 61         
 62         openButton = new JButton("\u786E\u5B9A");
 63         openButton.addActionListener(this);
 64         panel.add(openButton);
 65         
 66         scrollPane = new JScrollPane();
 67         contentPane.add(scrollPane, BorderLayout.CENTER);
 68         
 69         panel_1 = new JPanel();
 70         scrollPane.setViewportView(panel_1);
 71         panel_1.setLayout(new CardLayout(0, 0));
 72         
 73         text = new JTextArea();
 74         panel_1.add(text, "name_30136914873902");
 75         
 76         
 77     }
 78     public static void open(){
 79         FileInputStream fis=null;
 80         int i=0;
 81             try {
 82                 fis=new FileInputStream("F:/java资源/java中线程.txt");
 83             } catch (FileNotFoundException e1) {
 84                 // TODO 自动生成的 catch 块
 85                 e1.printStackTrace();
 86             }
 87 //        System.out.println(fis);
 88             try {
 89                 
 90                 fis.read();
 91             } catch (IOException e1) {
 92                 // TODO 自动生成的 catch 块
 93                 e1.printStackTrace();
 94             }
 95         
 96         //当i=-1时，文件到达文件尾部
 97         while(i !=-1){
 98                 try {
 99                     i=fis.read();
100                 } catch (IOException e1) {
101                     // TODO 自动生成的 catch 块
102                     e1.printStackTrace();
103                 }
104         }
105     }
106     
107     public  void input() throws Exception
108     {
109         File file = new File("F:/java资源/java中线程.txt");//读取文件
110         FileInputStream fi = new FileInputStream(file);//创建字节流，打开该 文件
111          byte[] b = new byte[fi.available()];//fi.available 可以获取文件占多少字节
112         int a = -1;
113          while((a= fi.read(b))!= -1)//判断文件是否到达文件末尾
114      {
115              //System.out.println(new String(b));
116          }
117 //         System.out.println(new String(b));
118          text.setText(new String(b));
119         //关闭流
120        fi.close();
121        }
122     @Override
123     public void actionPerformed(ActionEvent e) {
124         // TODO 自动生成的方法存根
125         if(e.getSource()==openButton){
126             try {
127                 input();
128             } catch (Exception e1) {
129                 // TODO 自动生成的 catch 块
130                 e1.printStackTrace();
131             }
132         }
133     }
134 }

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