第五次作业

import java.awt.;
import java.awt.event.;

import javax.swing.;
import javax.swing.event.;
import javax.swing.border.*;

import java.util.List;
import java.util.ArrayList;
import java.util.Iterator;

import java.io.*;

/**

• A simple sound player. To start, create an instance of this class.

• The sound player can play sound clips in WAV, AU and AIFF formats

• with standard sample rates.

• @author Michael Kolling and David J Barnes

• @version 1.0
  */
  public class SoundPlayerGUI extends JFrame
  implements ChangeListener, ActionListener
  {

  private final String AUDIO_DIR = "audio";

  private JList fileList;

  /**

  • Main method for starting the player from a command line.
    */
    public static void main(String[] args)
    {
    SoundPlayerGUI gui = new SoundPlayerGUI();
    }

  /**

  • Create a SoundPlayer and display its GUI on screen.
    */
    public SoundPlayerGUI()
    {
    super("SoundPlayer");

    String[] audioFileNames = findFiles(AUDIO_DIR, null);
    makeFrame(audioFileNames);
    }

  /**

  • Play the sound file currently selected in the file list. If there is no
  • selection in the list, or if the selected file is not a sound file,
  • do nothing.
    */

  private String[] findFiles(String dirName, String suffix)
  {
  File dir = new File(dirName);
  if(dir.isDirectory()) {
  String[] allFiles = dir.list();
  if(suffix == null) {
  return allFiles;
  }
  else {
  List selected = new ArrayList();
  for(String filename : allFiles) {
  if(filename.endsWith(suffix)) {
  selected.add(filename);
  }
  }
  return selected.toArray(new String[selected.size()]);
  }
  }
  else {
  System.out.println("Error: " + dirName + " must be a directory");
  return null;
  }
  }

  // ------- ChangeListener interface (for Slider) -------

  /**

  • ChangeListener method for slider changes. This method is called
  • when the slider value is changed by the user.
  • @param evt The event details.
    */

  private void makeFrame(String[] audioFiles)
  {
  // the following makes sure that our application exits when
  // the user closes its window

   JPanel contentPane = (JPanel)getContentPane();
  
  
   
   // Specify the layout manager with nice spacing
   contentPane.setLayout(new BorderLayout(8, 8));
  
   // Create the left side with combobox and scroll list
   JPanel leftPane = new JPanel();
   {
       leftPane.setLayout(new BorderLayout(8, 8));
  
    
  
       // Create the combo box.
     
       
  
       // Create the scrolled list for file names
       fileList = new JList(audioFiles);
       fileList.setForeground(new Color(140,171,226));
       fileList.setBackground(new Color(1,0,0));
       fileList.setSelectionBackground(new Color(87,49,134));
       fileList.setSelectionForeground(new Color(140,171,226));
       JScrollPane scrollPane = new JScrollPane(fileList);
       scrollPane.setColumnHeaderView(new JLabel("Audio files"));
       leftPane.add(scrollPane, BorderLayout.CENTER);
   }
   contentPane.add(leftPane, BorderLayout.CENTER);
  
   // Create the center with image, text label, and slider
  
   pack();
   
   // place this frame at the center of the screen and show
   Dimension d = Toolkit.getDefaultToolkit().getScreenSize();
   setLocation(d.width/2 - getWidth()/2, d.height/2 - getHeight()/2);
   setVisible(true);
  

  }

  @Override
  public void actionPerformed(ActionEvent arg0) {
  // TODO Auto-generated method stub

  }

  @Override
  public void stateChanged(ChangeEvent arg0) {
  // TODO Auto-generated method stub

  }

  }

import java.awt.BorderLayout;
import java.awt.Color;
import java.io.File;

import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JScrollPane;

public class FileUtils {

/**

• 列出指定目录下的所有文件和子目录的名称
• @throws IllegalAccessException

*/
public static void listDirectory(File dir) throws IllegalAccessException{
//判断File对象dir是否存在，使用File类的exists()方法
if(!dir.exists()){
//如不存在，抛出异常
throw new IllegalAccessException("目录" + dir +"不存在");
}
//判断dir是否是目录，使用File类的isDirectory()方法
if(!dir.isDirectory()){
//如果dir不是目录，抛出异常
throw new IllegalArgumentException(dir + "不是目录");
}
//获得指定目录dir下的文件及子目录并输出（1.list();2.listFiles()）
//使用list()方法实现
String[] fileName = dir.list();
for(String s :fileName){
System.out.println(dir + ""+ s);
}

System.out.println();
//使用listFiles()方法实现只列出目录下的所有文件名称
File[] files = dir.listFiles();
for(File file:files){
//如果是文件，则输出
if(file.isFile()){
System.out.println(file);
}
}

JFrame a =new JFrame("Text");
a.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
a.setLayout(new BorderLayout());
String[] AA ={".txt",".ppt",".jpg",".docx"};
JComboBox l1=new JComboBox(AA);
a.add(l1,BorderLayout.NORTH);
JList list = new JList(files);
list.setForeground(new Color(140,200,220));
list.setSelectionBackground(new Color(100,80,150));
list.setSelectionForeground(new Color(140,200,220));
JScrollPane sp = new JScrollPane(list);
//
a.add(sp,BorderLayout.CENTER);
a.setBounds(400,300,400,300);

a.setVisible(true);
}
public static void main(String[] args) {
// TODO Auto-generated method stub

try {
FileUtils.listDirectory(new File("E:"));
} catch (IllegalAccessException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

}

}