本文主要实现了进度条进度的实时显示

通过进行文件的复制功能来体现

编写一个可以实现复制文件功能的方法Filecopy()（为了方便并没有实现文件夹的复制，只是对单个文件进行的操作，并要求手动输入文件全名）

s1 是源文件的全名 s2是输出文件的全名

public void Filecopy(String s1,String s2)

Filecopy()方法中的progressBar.setStringPainted(true);是为了显示进度的百分比

为了实现进度条的进度随复制的进度实时显示，把Filecopy()放到子线程中

new Thread(new Runnable() {@Overridepublic void run() {// TODO Auto-generated method stubFilecopy(t1,t2); }}).start();

下面是整个Demo的code

import java.awt.BorderLayout;
import java.awt.EventQueue;import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JTextField;
import javax.swing.JProgressBar;
import javax.swing.JButton;
import java.awt.event.ActionListener;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.awt.event.ActionEvent;
/*** 文件复制程序* 编码采用UTF-8*/
public class jf1 extends JFrame {private JPanel contentPane;public JPanel panel;public JLabel label;public JTextField text_start;public JPanel panel_1;public JLabel label_1;public JTextField text_end;public JProgressBar progressBar;public JButton btnNewButton;/*** Launch the application.*/public static void main(String[] args) {EventQueue.invokeLater(new Runnable() {public void run() {try {jf1 frame = new jf1();frame.setVisible(true);} catch (Exception e) {e.printStackTrace();}}});}/*** Create the frame.*/public jf1() {setTitle("文件复制");setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);setBounds(100, 100, 611, 300);contentPane = new JPanel();contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));setContentPane(contentPane);contentPane.setLayout(null);panel = new JPanel();panel.setBounds(38, 28, 509, 43);contentPane.add(panel);panel.setLayout(null);label = new JLabel("原文件路径");label.setBounds(10, 0, 76, 43);panel.add(label);text_start = new JTextField();text_start.setBounds(115, 0, 380, 43);panel.add(text_start);text_start.setColumns(10);panel_1 = new JPanel();panel_1.setLayout(null);panel_1.setBounds(38, 95, 509, 43);contentPane.add(panel_1);label_1 = new JLabel("目标文件路径");label_1.setBounds(10, 0, 90, 43);panel_1.add(label_1);text_end = new JTextField();text_end.setColumns(10);text_end.setBounds(114, 0, 381, 43);panel_1.add(text_end);progressBar = new JProgressBar();progressBar.setBounds(40, 166, 496, 19);contentPane.add(progressBar);btnNewButton = new JButton("开始复制");btnNewButton.addActionListener(new BtnNewButtonActionListener());btnNewButton.setBounds(38, 201, 108, 40);contentPane.add(btnNewButton);}private class BtnNewButtonActionListener implements ActionListener {public void actionPerformed(ActionEvent arg0) {String t1 = text_start.getText();String t2 = text_end.getText();if(t1!=null&&t1!=""&&t2!=null&&t2!=""){try {new Thread(new Runnable() {@Overridepublic void run() {// TODO Auto-generated method stubFilecopy(t1,t2);}}).start();} catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();}}}}/*** 文件复制的方法*/public void Filecopy(String s1,String s2){progressBar.setValue(0);if(s1.equals("")||s1==null) {JOptionPane.showMessageDialog(null, "源文件不能为空");return;}if(s2.equals("")||s2==null) {JOptionPane.showMessageDialog(null, "目标文件不能为空");return;}FileInputStream fis = null;try {fis = new FileInputStream(s1);} catch (FileNotFoundException e) {// TODO Auto-generated catch blockJOptionPane.showMessageDialog(null, "源文件不存在");return;}//目标文件的总字节数int flen = 0;try {flen = fis.available();} catch (IOException e) {// TODO Auto-generated catch blockJOptionPane.showMessageDialog(null, "源文件获取失败");return;}//System.out.println(flen);int js = JOptionPane.showConfirmDialog(null, "文件大小为："+flen+" B是否复制?", "文件复制", JOptionPane.YES_NO_OPTION);//System.out.println(js);if(js==0) {FileOutputStream fos = null;try {fos = new FileOutputStream(s2);} catch (FileNotFoundException e) {// TODO Auto-generated catch blockJOptionPane.showMessageDialog(null, "目标文件输出位置有误");return;}DataInputStream dis = new DataInputStream(fis);DataOutputStream dos = new DataOutputStream(fos);byte [] buf = new byte[1024];int icu = 0;//当前已复制字节总数int progress = 0 ;try {while((icu = dis.read(buf, 0, 1024))!=-1){dos.write(buf, 0, icu);dos.flush();progress+=icu;progressBar.setValue((int) (((double)progress/flen)*100));progressBar.setStringPainted(true);}} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}try {fos.close();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}try {dos.close();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}try {dis.close();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}FileInputStream fischeck = null;try {fischeck = new FileInputStream(s2);} catch (FileNotFoundException e) {// TODO Auto-generated catch blockJOptionPane.showMessageDialog(null, "文件复制失败");return;}JOptionPane.showMessageDialog(null, "文件复制成功");try {fischeck.close();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}try {fis.close();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}
}