ftpclientdemo.java

java经典10例子

/*
 *Java实现ftp功能(源程序)
 **/
import sun.net.ftp.*; 
import sun.net.*; 
import java.awt.*; 
import java.awt.event.*; 
import java.applet.*; 
import java.io.*; 

public class FtpClientDemo extends Applet { 
	FtpClient aftp;//利用FtpClient类
	DataOutputStream outputs ; 
	TelnetInputStream ins; 
	TelnetOutputStream outs; 
	TextArea lsArea; 
	Label    LblPrompt; 
	Button   BtnConn; 
	Button   BtnClose; 
	TextField  TxtUID; 
	TextField  TxtPWD; 
	TextField  TxtHost; 
	int ch; 
	public String a="没有连接主机"; 
	String hostname=""; 
	public void init (){ 
		setBackground(Color.white); 
		setLayout(new GridBagLayout()); 
		GridBagConstraints GBC = new GridBagConstraints(); 
		LblPrompt = new Label("没有连接主机"); 
		LblPrompt.setAlignment(Label.LEFT); 
	
		BtnConn = new Button("连接"); 
		BtnClose = new Button("断开"); 
		BtnClose.enable(false); 
		TxtUID = new TextField("",10); 
		TxtPWD = new TextField("",10); 
		TxtPWD.setEchoCharacter('*'); 
		TxtHost = new TextField("",15); 
		Label LblUID = new Label("User ID:"); 
		Label LblPWD = new Label("PWD:"); 
		Label LblHost = new Label("Host:"); 
	
		lsArea = new TextArea(10,20); 
		lsArea.setEditable(false); 
	
		GBC.gridwidth= GridBagConstraints.REMAINDER; 
		GBC.fill     = GridBagConstraints.HORIZONTAL; 
		((GridBagLayout)getLayout()).setConstraints(LblPrompt,GBC); 
		add(LblPrompt); 
	
		GBC.gridwidth=1; 
		((GridBagLayout)getLayout()).setConstraints(LblHost,GBC); 
		add(LblHost); 
		GBC.gridwidth=GridBagConstraints.REMAINDER; 
		((GridBagLayout)getLayout()).setConstraints(TxtHost,GBC); 
		add(TxtHost); 
	
		GBC.gridwidth=1; 
		((GridBagLayout)getLayout()).setConstraints(LblUID,GBC); 
		add(LblUID); 
		GBC.gridwidth=1; 
		((GridBagLayout)getLayout()).setConstraints(TxtUID,GBC); 
		add(TxtUID); 
	
		GBC.gridwidth=1; 
		((GridBagLayout)getLayout()).setConstraints(LblPWD,GBC); 
		add(LblPWD); 
		GBC.gridwidth=1; 
		((GridBagLayout)getLayout()).setConstraints(TxtPWD,GBC); 
		add(TxtPWD); 
	
		GBC.gridwidth=1; 
		GBC.weightx=2; 
		((GridBagLayout)getLayout()).setConstraints(BtnConn,GBC); 
		add(BtnConn); 
		GBC.gridwidth=GridBagConstraints.REMAINDER; 
	
		((GridBagLayout)getLayout()).setConstraints(BtnClose,GBC); 
		add(BtnClose); 
	
		GBC.gridwidth=GridBagConstraints.REMAINDER; 
		GBC.fill     = GridBagConstraints.HORIZONTAL; 
		((GridBagLayout)getLayout()).setConstraints(lsArea,GBC); 
		add(lsArea); 
	} 
	
	public boolean connect(String hostname, String uid,String pwd) { 
		this.hostname = hostname; 
		LblPrompt.setText("正在连接，请等待....."); 
		try{ 
	  		aftp =new FtpClient(hostname); 
	  		aftp.login(uid,pwd); 
	  		aftp.binary(); 
	  		showFileContents(); 
		} catch(FtpLoginException e){ 
			a="无权限与主机:"+hostname+"连接!"; 
			LblPrompt.setText(a); 
			return false; 
		} catch (IOException e){ 
			a="连接主机:"+hostname+"失败!"; 
			LblPrompt.setText(a); 
			return false; 
		} catch(SecurityException e) { 
			a="无权限与主机:"+hostname+"连接!"; 
			LblPrompt.setText(a); 
			return false; 
		} 
		LblPrompt.setText("连接主机:"+hostname+"成功!"); 
		return true; 
	} 
	
	public void stop() { 
		try { 
			aftp.closeServer(); 
		} catch(IOException e) { } 
	} 
	
	public void paint(Graphics g){ } 
	
	public boolean action(Event evt,Object obj) { 
		if (evt.target == BtnConn) { 
			LblPrompt.setText("正在连接，请等待....."); 
			if (connect(TxtHost.getText(),TxtUID.getText(),
                  TxtPWD.getText())) { 
				BtnConn.setEnabled(false); 
				BtnClose.setEnabled(true); 
			} 
			return true; 
		} 
		if (evt.target == BtnClose) { 
			stop(); 
			BtnConn.enable(true); 
			BtnClose.enable(false); 
			LblPrompt.setText("与主机"+hostname+"连接已断开!"); 
			return true; 
		} 
		return super.action(evt,obj); 
	} 
	public boolean sendFile(String filepathname){ 
		boolean result=true; 
		if (aftp != null) { 
			LblPrompt.setText("正在粘贴文件,请耐心等待...."); 
	
			String  contentperline; 
			try{ 
				a="粘贴成功!"; 
				String fg =new  String("\\"); 
				int index = filepathname.lastIndexOf(fg); 
				String filename = filepathname.substring(index+1); 
				File localFile ; 
				localFile = new File(filepathname) ; 
				RandomAccessFile sendFile = new RandomAccessFile(filepathname,"r"); 
				sendFile.seek(0); 
				outs = aftp.put(filename); 
				outputs = new DataOutputStream(outs); 
				while (sendFile.getFilePointer() < sendFile.length() ) { 
	  				ch = sendFile.read(); 
	  				outputs.write(ch); 
				} 
				outs.close(); 
				sendFile.close(); 
			} catch(IOException e){ 
	  			a = "粘贴失败!"; 
	  			result = false ; 
			} 
			LblPrompt.setText(a); 
			showFileContents(); 
		} else{ 
			result = false; 
		} 
		return result; 
	} 
	
	public void showFileContents() { 
		StringBuffer buf = new StringBuffer(); 
		lsArea.setText(""); 
		try { 
			ins= aftp.list(); 
			while ((ch=ins.read())>=0){ 
	  			buf.append((char)ch); 
			} 
	    	lsArea.appendText(buf.toString()); 
			ins.close(); 
	    } catch(IOException e) { } 
	} 
	
	public static void main(String args[]){ 
	    Frame f = new Frame("FTP Client"); 
	    f.addWindowListener(new WindowAdapter(){ 
	    	public void windowClosing(WindowEvent e){ 
	    		System.exit(0); 
	    	} 
		}); 
	    FtpClientDemo ftp = new  FtpClientDemo(); 
	    ftp.init(); 
	    ftp.start(); 
	    f.add(ftp); 
	    f.setSize(200,300);
	    f.pack(); 
	   	f.setVisible(true); 
	} 
}