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java实现在复制文件时使用进度条(java实现进度条)

思路分析:

因为既要有操作面板又要有进度条,所以肯定要出现两个继承JFrame类的窗体。先看被调用的进度条窗体,它不需要手动操作,所以类的内部实现一个方法就可以了。因为设计文件操作,所以要捕获异常。首先根据要复制的文件创建File对象,以及根据复制后文件的保存地址创建File对象,然后创建FileOutputStream对象,再创建FileInputStream对象,之后是ProgressMonitorInputStream对象,然后读取文件,如果总耗时超过2秒,将会自动弹出一个进度监视窗口。接下来定义byte数组,再使用while循环读取文件,使用FileOutputStream类的write()方法通过流写数据,再使用FileOutputStream类的close()方法关闭输出流,最后使用ProgressMonitorInputStream类的close()方法关闭输入流。可见该方法需要三个参数:弹出它的父窗口、要复制的文件地址以及要复制到的文件夹。代码如下:

ProgressMonitorTest.java:

代码如下:
package cn.edu.xidian.crytoll;import java.io.FileInputStream;import java.io.*;import javax.swing.JFrame;import javax.swing.ProgressMonitorInputStream;public class ProgressMonitorTest {    public void useProgressMonitor(JFrame frame, String copyPath, String newPath) {        try {            File file = new File(copyPath); // 根据要复制的文件创建File对象            File newFile = new File(newPath); // 根据复制后文件的保存地址创建File对象            FileOutputStream fop = new FileOutputStream(newFile); // 创建FileOutputStream对象            InputStream in = new FileInputStream(file);            // 读取文件,如果总耗时超过2秒,将会自动弹出一个进度监视窗口。            ProgressMonitorInputStream pm = new ProgressMonitorInputStream(                    frame, “文件读取中,请稍后…”, in);            int c = 0;            byte[] bytes = new byte[1024]; // 定义byte数组            while ((c = pm.read(bytes)) != -1) { // 循环读取文件                fop.write(bytes, 0, c); // 通过流写数据            }            fop.close(); // 关闭输出流            pm.close(); // 关闭输入流        } catch (Exception ex) {            ex.printStackTrace();        }    }}

3. 再看主窗体。JLabel、JTextField神马的就不用说了,选择文件和选择文件夹这两个按钮也是老生常谈了,最重要的是“开始复制”按钮,将由它来负责弹出这个进度条,这就需要开辟一个新的线程,所以主窗体不仅要继承JFrame类,还要实现Runnable接口。他大爷的。

4. 在开始复制按钮的具体方法里,首先创建一个Thread对象作为新的线程,然后调用该对象的start()方法,重载执行run()方法,在该方法中创建一个进度条对象,使用JTextField类的getText()方法获取要复制的文件地址和要复制到的路径,然后调用进度条类里的方法。

代码如下:

代码如下:
package cn.edu.xidian.crytoll;import java.awt.BorderLayout;import java.awt.Desktop;import java.awt.Dimension;import java.awt.EventQueue;import java.awt.GridBagConstraints;import java.awt.GridBagLayout;import java.awt.Insets;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import java.io.File;import java.io.FileNotFoundException;import java.io.FileReader;import java.io.FileWriter;import java.io.IOException;import javax.swing.JButton;import javax.swing.JFileChooser;import javax.swing.JFrame;import javax.swing.JLabel;import javax.swing.JOptionPane;import javax.swing.JPanel;import javax.swing.JTextField;import javax.swing.border.EmptyBorder;import javax.swing.filechooser.FileNameExtensionFilter;public class UserMonitorFrame extends JFrame implements Runnable{    /**     *      */    private static final long serialVersionUID = 8674569541853793419L;    private JPanel contentPane;    private JTextField fileField;    private JTextField searchTextField;    private JTextField replaceTextField;    private File file;    private JTextField textField;    private JTextField textField_1;    /**     * Launch the application.     */    public static void main(String[] args) {        EventQueue.invokeLater(new Runnable() {            public void run() {                try {                    UserMonitorFrame frame = new UserMonitorFrame();                    frame.setVisible(true);                } catch (Exception e) {                    e.printStackTrace();                }            }        });    }    /**     * Create the frame.     */    public UserMonitorFrame() {        setResizable(false);        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);        setBounds(100, 100, 501, 184);        setTitle(“在读取文件时使用进度条”);        getContentPane().setLayout(null);        JLabel label = new JLabel(“\u6587\u4EF6\u5730\u5740\uFF1A”);        label.setBounds(10, 10, 70, 15);        getContentPane().add(label);        textField = new JTextField();        textField.setBounds(90, 7, 300, 21);        getContentPane().add(textField);        textField.setColumns(10);        JButton button = new JButton(“\u9009\u62E9\u6587\u4EF6”);        button.addActionListener(new ActionListener() {            public void actionPerformed(ActionEvent e) {                do_button_actionPerformed(e);            }        });        button.setBounds(400, 6, 93, 23);        getContentPane().add(button);        JLabel label_1 = new JLabel(“\u590D\u5236\u5730\u5740\uFF1A”);        label_1.setBounds(10, 40, 70, 15);        getContentPane().add(label_1);        textField_1 = new JTextField();        textField_1.setBounds(90, 38, 300, 21);        getContentPane().add(textField_1);        textField_1.setColumns(10);        JButton button_1 = new JButton(“\u9009\u62E9\u5730\u5740”);        button_1.addActionListener(new ActionListener() {            public void actionPerformed(ActionEvent e) {                do_button_1_actionPerformed(e);            }        });        button_1.setBounds(400, 39, 93, 23);        getContentPane().add(button_1);        JButton button_2 = new JButton(“\u5F00\u59CB\u590D\u5236”);        button_2.addActionListener(new ActionListener() {            public void actionPerformed(ActionEvent e) {                do_copyButton_actionPerformed(e);            }        });        button_2.setBounds(182, 69, 93, 23);        getContentPane().add(button_2);    }    protected void do_button_actionPerformed(ActionEvent e){        JFileChooser chooser=new JFileChooser();        chooser.setFileSelectionMode(JFileChooser.FILES_ONLY);        // 显示文件打开对话框        int option = chooser.showOpenDialog(this);        // 确定用户按下打开按钮,而非取消按钮        if (option != JFileChooser.APPROVE_OPTION)            return;        // 获取用户选择的文件对象        file = chooser.getSelectedFile();        // 显示文件信息到文本框        textField.setText(file.toString());    }    protected void do_button_1_actionPerformed(ActionEvent e){        JFileChooser chooser=new JFileChooser();        chooser.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY);        int option=chooser.showOpenDialog(this);        if(option!=JFileChooser.APPROVE_OPTION)            return;        file=chooser.getSelectedFile();        textField_1.setText(file.toString());    }  //确定复制按钮单击事件    protected void do_copyButton_actionPerformed(ActionEvent arg0) {       Thread thread = new Thread(this);       thread.start();    }   //应用多线程技术实现读取操作    @Override    public void run() {        ProgressMonitorTest test = new ProgressMonitorTest();        String path = textField.getText();        String save = textField_1.getText();        test.useProgressMonitor(this,path,save+path.substring(path.lastIndexOf(“.”),path.length()));    }}

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