服务器代码：
package day21.xl;
import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileFilter;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
public class FtpServer {
public static void main(String[] args)throws IOException {
FtpServer server=new FtpServer();
server.listen(8080);
}
public void listen(int port)throws IOException{
ServerSocket ss=new ServerSocket(port);
//System.out.println("欢迎使用FTP Demo软件！");
while(true){
System.out.println("等待客户连接...");
Socket socket=ss.accept();
System.out.println("连接成功!");
new ClientAgent(socket).start();
}
}
class ClientAgent extends Thread{
Socket socket;
InputStream in;
OutputStream out;
public ClientAgent(Socket socket) throws IOException{
this.socket=socket;
in=socket.getInputStream();
out=socket.getOutputStream();
}
@Override
public void run() {
BufferedReader in=new BufferedReader(new InputStreamReader(this.in));
PrintWriter out=new PrintWriter(this.out, true);
out.println("text,1");
out.println("欢迎使用《Ftp》传输软件！");
while(true){
try {
String cmd=in.readLine();
if("?".trim().equals(cmd)){
out.println("text,1");
out.println("支持命令：ls,get,?,bye");
}else if("ls".trim().equals(cmd)){
listDir(out);
}else if(cmd.matches("^get\\s+.+")){
sendFile(cmd, out, this.out);
}else{
out.println("text,1");
out.println("不知可否！");
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
private void sendFile(String cmd, PrintWriter out, OutputStream os) throws IOException {
String name=cmd.split("\\s+")[1];
File file=new File(name);
if(! file.exists()){
out.println("text,1");
out.println("没有该文件!"+name);
return;
}
out.println("file,"+file.length()+","+name);
InputStream in=new BufferedInputStream(new FileInputStream(file));
int b;
while((b=in.read())!=-1){
os.write(b);
}
os.flush();
out.flush();
in.close();
}
private void listDir(PrintWriter out) {
File dir=new File(".");
File[] files=dir.listFiles(new FileFilter(){
@Override
public boolean accept(File pathname) {
return pathname.isFile();
}
});
out.println("text,"+files.length+1);
out.println("在目录"+dir+"中，有文件"+files.length);
for(File file : files){
out.println(file.getName());
}
out.flush();
}
}
}
客户端代码：
package day21.xl;
import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.Socket;
public class FtpClient {
Socket socket;
InputStream in;
OutputStream out;
public static void main(String[] args)throws IOException {
FtpClient server=new FtpClient();
server.open("localhost",8080);
}
public void open(String host,int port)throws IOException{
socket=new Socket(host,port);
in=socket.getInputStream();
out=socket.getOutputStream();
new RequestSender(out).start();
new ResponseReceiver(in).start();
}
class RequestSender extends Thread{
OutputStream out;
public RequestSender(OutputStream out){
this.out=out;
}
@Override
public void run() {
PrintWriter out=new PrintWriter(this.out, true);
BufferedReader in=new BufferedReader(new InputStreamReader(System.in));
String str;
try {
while((str=in.readLine())!=null){
out.println(str);
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
class ResponseReceiver extends Thread{
InputStream in;
public ResponseReceiver(InputStream in){
this.in=in;
}
@Override
public void run() {
BufferedReader in=new BufferedReader(new InputStreamReader(this.in));
String str;
try {
while((str=in.readLine())!=null){
if(str.startsWith("text")){
String num=str.substring(str.indexOf(",")+1);
printText(in,Integer.parseInt(num));
}else if(str.startsWith("file")){
saveFile(this.in, str);
}
}
} catch (IOException e) {
e.printStackTrace();
}
}
private void saveFile(InputStream in, String head)throws IOException {
String[] data=head.split(",");
int length=Integer.parseInt(data[1]);
String name=data[2];
OutputStream out=new BufferedOutputStream(new FileOutputStream("ftp-"+name));
for(int i=0;i<length;i++){
int b=in.read();
out.write(b);
}
out.flush();
out.close();
System.out.println(name+"下载成功！");
}
private void printText(BufferedReader in, int num) throws IOException {
for(int i=0;i<num;i++){
System.out.println(in.readLine());
}
}
}
}
当我运行get 下载功能时，测试结果为
第一次输入get text.txt结果显示：
get text.txt
file,19,text.txt
第二次输入get text.txt结果为：
get text.txt
A中接口bc中中试试吧file,19,text.txt
我想要的结果是，输入get text.txt命令之后再本地磁盘上会出现一个 ftp-text.txt这个文件。但是输入结果是file,19,text.txt；
我想应该是没有清空缓存的结果吧？但是我吧所有的流都.flush()了一遍。结果还是这样。请大神们指点！小弟已经研究一天了，找不出哪里错了。小弟在此感谢所有进来看的大神们。
