urlfile.java

《Java实例入门》所有实例的源代码。所有的源文件都是.java文件

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

public class UrlFile extends Frame
   implements ActionListener{
  private URL   url;
  Label lblHost,lblIP,lblPort,lblProtocol,lblFile;
  TextField FileName;
  Button getButton;
  public UrlFile() {
      super("利用URL得到网络文件");
      setSize(400,400);
      setBackground(Color.lightGray);
      setGUI();
      addWindowListener(new WindowAdapter(){
                   public void windowClosing(WindowEvent e){
                           System.exit(0);
                    }
                                            }
                        );
      pack();
      show();
  }
  private void setGUI(){
      Panel pNorth=new Panel();
      pNorth.add(new Label("URL文件:"));
      pNorth.add(FileName=new TextField());
      FileName.setColumns(25);
      pNorth.add(getButton=new Button("提取文件信息"));
      getButton.addActionListener(this);
      this.add("North",pNorth);
      Panel pCenter=new Panel();
      pCenter.setLayout(new GridLayout(5,2)) ;
      pCenter.add(new Label("主机名：   ",Label.RIGHT ));
      pCenter.add(lblHost=new Label("",Label.LEFT ));
      pCenter.add(new Label("主机IP地址：   ",Label.RIGHT ));
      pCenter.add(lblIP=new Label("",Label.LEFT));
      pCenter.add(new Label("端口：   ",Label.RIGHT ));
      pCenter.add(lblPort=new Label("",Label.LEFT));
      pCenter.add(new Label("协议名称：   ",Label.RIGHT ));
      pCenter.add(lblProtocol=new Label("",Label.LEFT));
      pCenter.add(new Label("文件名：   ",Label.RIGHT ));
      pCenter.add(lblFile=new Label("",Label.LEFT));
      this.add("Center",pCenter);
  }
  public void actionPerformed(ActionEvent e){
       Object obj = e.getSource();
      if(obj==getButton) {
         if(url!=null) url=null;
         try{
              url=new URL(FileName.getText() );
              getInfo();
              saveFile();
         }catch(Exception ex){
             System.out.println(ex);
         }
      }
   }
   private void getInfo(){
      try{
           lblHost.setText(url.getHost());
           lblProtocol.setText(url.getProtocol());
           InetAddress host=InetAddress.getByName(url.getHost());
           lblIP.setText(host.getHostAddress());
           Integer port=new Integer(url.getPort());
           lblPort.setText(port.toString());
           lblFile.setText(url.getPath() );

      }catch(Exception e){
            System.out.println(e);
      }
   }
   private void saveFile(){
      try{

           DataInputStream inStream=new DataInputStream(url.openStream() );
           File file=new File("."+url.getFile() );
           mkdir(file.getParent());
           DataOutputStream outputStream = new DataOutputStream(new FileOutputStream(file));
          int count=0;
          try{
               while(true) {
                   outputStream.writeByte((int)inStream.readByte()) ;
                }
           }catch(EOFException eofEx){
               inStream.close();
               outputStream.flush();
               outputStream.close();
               System.out.println(eofEx);
           }
      }catch(Exception e){
            System.out.println(e);
      }
   }
  private void mkdir(String strfileName) {
     try{
         File newFile=new File(strfileName);
         File parentFile=new File(newFile.getParent());
        if( !parentFile.exists() )  mkdir(newFile.getParent() );
           newFile.mkdir();
      }catch(Exception e){
      }
  }
  static public void main(String argv[]){
      new UrlFile();
   }
}