好吧，我正在尝试用Java实现ftp服务器和ftp客户端。我试图从服务器接收文件。以下是代码行。我能够实现服务器和客户端之间的连接，但也无法将文件名发送到服务器。那么任何人都可以指导我这种方法是否正确，或者如果没有，请建议适当的更改。
服务器的实施：
import java.net.*;
import java.io.*;
class MyServer {
ServerSocket ss;
Socket clientsocket;
BufferedReader fromclient;
InputStreamReader isr;
PrintWriter toclient;
public MyServer() {
String str = new String("hello");
try {
// Create ServerSocket object.
ss = new ServerSocket(1244);
System.out.println("Server Started...");
while(true) {
System.out.println("Waiting for the request...");
// accept the client request.
clientsocket = ss.accept();
System.out.println("Got a client");
System.out.println("Client Address " + clientsocket.getInetAddress().toString());
isr = new InputStreamReader(clientsocket.getInputStream());
fromclient = new BufferedReader(isr);
toclient = new PrintWriter(clientsocket.getOutputStream());
String strfile;
String stringdata;
boolean file_still_present = false;
strfile = fromclient.readLine();
System.out.println(strfile);
//toclient.println("File name received at Server is " + strfile);
File samplefile = new File(strfile);
FileInputStream fileinputstream = new FileInputStream(samplefile);
// now ready to send data from server .....
int notendcharacter;
do {
notendcharacter = fileinputstream.read();
stringdata = String.valueOf(notendcharacter);
toclient.println(stringdata);
if (notendcharacter != -1) {
file_still_present = true;
} else {
file_still_present = false;
}
} while(file_still_present);
fileinputstream.close();
System.out.println("File has been send successfully .. message print from server");
if (str.equals("bye")) {
break;
}
fromclient.close();
toclient.close();
clientsocket.close();
}
} catch(Exception ex) {
System.out.println("Error in the code : " + ex.toString());
}
}
public static void main(String arg[]) {
MyServer serverobj = new MyServer();
}
}
客户的实施：
import java.net.*;
import java.io.*;
class MyClient {
Socket soc;
BufferedReader fromkeyboard, fromserver;
PrintWriter toserver;
InputStreamReader isr;
public MyClient() {
String str;
try {
// server is listening on this port.
soc = new Socket("localhost", 1244);
fromkeyboard = new BufferedReader(new InputStreamReader(System.in));
fromserver = new BufferedReader(new InputStreamReader(soc.getInputStream()));
System.out.println("PLEASE ENTER THE MESSAGE TO BE SENT TO THE SERVER");
str = fromkeyboard.readLine();
System.out.println(str);
String ddd;
ddd = str;
toserver = new PrintWriter(soc.getOutputStream());
String strfile;
int notendcharacter;
boolean file_validity = false;
System.out.println("send to server" + str);
System.out.println("Enter the filename to be received from server");
strfile = fromkeyboard.readLine();
toserver.println(strfile);
File samplefile = new File(strfile);
//File OutputStream helps to get write the data from the file ....
FileOutputStream fileOutputStream = new FileOutputStream(samplefile);
// now ready to get the data from server ....
do {
str = fromserver.readLine();
notendcharacter = Integer.parseInt(str);
if (notendcharacter != -1) {
file_validity = true;
} else {
System.out.println("Read and Stored all the Data Bytes from the file ..." +
"Received File Successfully");
}
if (file_validity) {
fileOutputStream.write(notendcharacter);
}
} while(file_validity);
fileOutputStream.close();
toserver.close();
fromserver.close();
soc.close();
} catch(Exception ex) {
System.out.println("Error in the code : " + ex.toString());
}
}
public static void main(String str[]) {
MyClient clientobj = new MyClient();
}
}
答案 0 :(得分：4)
上述问题的答案是：
FTP客户端：
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.Socket;
public class FileClient {
public static void main(String[] args) throws Exception {
long start = System.currentTimeMillis();
// localhost for testing
Socket sock = new Socket("127.0.0.1", 13267);
System.out.println("Connecting...");
InputStream is = sock.getInputStream();
// receive file
new FileClient().receiveFile(is);
OutputStream os = sock.getOutputStream();
//new FileClient().send(os);
long end = System.currentTimeMillis();
System.out.println(end - start);
sock.close();
}
public void send(OutputStream os) throws Exception {
// sendfile
File myFile = new File("/home/nilesh/opt/eclipse/about.html");
byte[] mybytearray = new byte[(int) myFile.length() + 1];
FileInputStream fis = new FileInputStream(myFile);
BufferedInputStream bis = new BufferedInputStream(fis);
bis.read(mybytearray, 0, mybytearray.length);
System.out.println("Sending...");
os.write(mybytearray, 0, mybytearray.length);
os.flush();
}
public void receiveFile(InputStream is) throws Exception {
int filesize = 6022386;
int bytesRead;
int current = 0;
byte[] mybytearray = new byte[filesize];
FileOutputStream fos = new FileOutputStream("def");
BufferedOutputStream bos = new BufferedOutputStream(fos);
bytesRead = is.read(mybytearray, 0, mybytearray.length);
current = bytesRead;
do {
bytesRead = is.read(mybytearray, current,
(mybytearray.length - current));
if (bytesRead >= 0)
current += bytesRead;
} while (bytesRead > -1);
bos.write(mybytearray, 0, current);
bos.flush();
bos.close();
}
}
FTP服务器：
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
public class FileServer {
public static void main(String[] args) throws Exception {
// create socket
ServerSocket servsock = new ServerSocket(13267);
while (true) {
System.out.println("Waiting...");
Socket sock = servsock.accept();
System.out.println("Accepted connection : " + sock);
OutputStream os = sock.getOutputStream();
//new FileServer().send(os);
InputStream is = sock.getInputStream();
new FileServer().receiveFile(is);
sock.close();
}
}
public void send(OutputStream os) throws Exception {
// sendfile
File myFile = new File("/home/nilesh/opt/eclipse/about.html");
byte[] mybytearray = new byte[(int) myFile.length() + 1];
FileInputStream fis = new FileInputStream(myFile);
BufferedInputStream bis = new BufferedInputStream(fis);
bis.read(mybytearray, 0, mybytearray.length);
System.out.println("Sending...");
os.write(mybytearray, 0, mybytearray.length);
os.flush();
}
public void receiveFile(InputStream is) throws Exception {
int filesize = 6022386;
int bytesRead;
int current = 0;
byte[] mybytearray = new byte[filesize];
FileOutputStream fos = new FileOutputStream("def");
BufferedOutputStream bos = new BufferedOutputStream(fos);
bytesRead = is.read(mybytearray, 0, mybytearray.length);
current = bytesRead;
do {
bytesRead = is.read(mybytearray, current,
(mybytearray.length - current));
if (bytesRead >= 0)
current += bytesRead;
} while (bytesRead > -1);
bos.write(mybytearray, 0, current);
bos.flush();
bos.close();
}
}
答案 1 :(得分：0)
＆GT;
import java.io.*;
import java.net.*;
class serversvi
{
public static void main(String svi[])throws IOException
{
try
{
ServerSocket servsock=new ServerSocket(105);
DataInputStream dis=new DataInputStream(System.in);
System.out.println("enter the file name");
String fil=dis.readLine();
System.out.println(fil+" :is file transfer");
File myfile=new File(fil);
while(true)
{
Socket sock=servsock.accept();
byte[] mybytearray=new byte[(int)myfile.length()];
BufferedInputStream bis=new BufferedInputStream(new FileInputStream(myfile));
bis.read(mybytearray,0,mybytearray.length);
OutputStream os=sock.getOutputStream();
os.write(mybytearray,0,mybytearray.length);
os.flush();
sock.close();
}
}
catch(Exception saranvi)
{
System.out.print(saranvi);
}
}
}
>
import java.io.*;
import java.net.*;
class clientsvi
{
public static void main(String svi[])throws IOException
{
try
{
Socket sock=new Socket("localhost",105);
byte[] bytearray=new byte[1024];
InputStream is=sock.getInputStream();
DataInputStream dis=new DataInputStream(System.in);
System.out.println("enter the file name");
String fil=dis.readLine();
FileOutputStream fos=new FileOutputStream(fil);
BufferedOutputStream bos=new BufferedOutputStream(fos);
int bytesread=is.read(bytearray,0,bytearray.length);
bos.write(bytearray,0,bytesread);
System.out.println("out.txt file is received");
bos.close();
sock.close();
}
catch(Exception SVI)
{
System.out.print(SVI);
}
}
}