ftp.java

java应用开发详解

import java.io.*;
import FtpClient;

public class Ftp
{
	public static void usage() {
		System.out.println("Usage : ftp host\n");
		System.exit(1);
	}
	
	public static void printResponse (String[] resIn) throws IOException {
		for (int i=0; i < resIn.length; i++) {
		if (resIn[i].length()!=0) {
				System.out.println (resIn[i]);
			}
		}
	}

	private static boolean login(BufferedReader k, FtpClient ftpc) throws IOException {
		String input="";
		boolean result=true;

		System.out.print("Username: ");
		input = k.readLine();
		result = ftpc.executeCommand("USER "+input);
		printResponse(ftpc.getResponseStream());
		if (result) return true;
		
		System.out.print("Password: ");
		input = k.readLine();
		result = ftpc.executeCommand("PASS "+input);
		printResponse(ftpc.getResponseStream());
		return (result);
	}
	
	public static void main(String[] args) throws IOException {
		FtpClient client = null;
		
	    if (args.length != 1) {
			usage();
		}
		try {
			client = new FtpClient(args[0]);
			
			String[] answer=client.getResponseStream();
			
			if (answer[0].equals("")) {
				System.err.println("Not able to connect to server "+args[0]+"\r\n");
				System.exit(1);
			}
			
			printResponse(answer);
			
			boolean exit = false;
			BufferedReader keyb = new BufferedReader(new InputStreamReader (System.in));
			String input=""; 
			boolean result=true;
			
			if(result=login(keyb,client)) {
				exit=true;		
			}
			
			while (!exit) {
				System.out.print ("ftp> ");
				input = keyb.readLine();
				exit = client.executeCommand (input);
				printResponse(client.getResponseStream());
			}
		}
		catch (Exception e) {
		}
	}
}