好的,尝试通过套接字传输指定目录中的文件,从数组列表中删除目录对象,这样就只剩下文件,然后通过同一个套接字逐个传输它们。数组...
好的,尝试通过套接字传输指定目录中的文件,从数组列表中删除目录对象,这样只剩下文件,然后通过同一个套接字逐个传输它们。这里的数组列表只填充了文件,没有目录。以下分别是客户端和服务器的接收和发送代码。代码运行良好,没有错误,除了所有数据都被写入第一个文件。后续文件在服务器文件夹中创建,但它们是 0 字节。任何输入都将不胜感激。
这是接收文件的服务器代码
public void receive(){
try {
DataInputStream dis = new DataInputStream(new BufferedInputStream(socket.getInputStream()));
DataOutputStream dos = new DataOutputStream(new BufferedOutputStream(socket.getOutputStream()));
//read the number of files from the client
int number = dis.readInt();
ArrayList<File>files = new ArrayList<File>(number);
System.out.println("Number of Files to be received: " +number);
//read file names, add files to arraylist
for(int i = 0; i< number;i++){
File file = new File(dis.readUTF());
files.add(file);
}
int n = 0;
byte[]buf = new byte[4092];
//outer loop, executes one for each file
for(int i = 0; i < files.size();i++){
System.out.println("Receiving file: " + files.get(i).getName());
//create a new fileoutputstream for each new file
FileOutputStream fos = new FileOutputStream("C:\\users\\tom5\\desktop\\salestools\\" +files.get(i).getName());
//read file
while((n = dis.read(buf)) != -1){
fos.write(buf,0,n);
fos.flush();
}
fos.close();
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
这是发送文件的客户端代码
public void send(ArrayList<File>files){
try {
DataInputStream dis = new DataInputStream(new BufferedInputStream(socket.getInputStream()));
DataOutputStream dos = new DataOutputStream(new BufferedOutputStream(socket.getOutputStream()));
System.out.println(files.size());
//write the number of files to the server
dos.writeInt(files.size());
dos.flush();
//write file names
for(int i = 0 ; i < files.size();i++){
dos.writeUTF(files.get(i).getName());
dos.flush();
}
//buffer for file writing, to declare inside or outside loop?
int n = 0;
byte[]buf = new byte[4092];
//outer loop, executes one for each file
for(int i =0; i < files.size(); i++){
System.out.println(files.get(i).getName());
//create new fileinputstream for each file
FileInputStream fis = new FileInputStream(files.get(i));
//write file to dos
while((n =fis.read(buf)) != -1){
dos.write(buf,0,n);
dos.flush();
}
//should i close the dataoutputstream here and make a new one each time?
}
//or is this good?
dos.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
您正在读取套接字,直到 read()
返回 -1。这是流结束条件 (EOS)。当对等方关闭连接时会发生 EOS。而不是在完成写入一个文件时。
您需要在每个文件之前发送文件大小。您已经对文件数量做了类似的事情。然后确保您读取了该文件的确切字节数:
String filename = dis.readUTF();
long fileSize = dis.readLong();
FileOutputStream fos = new FileOutputStream(filename);
while (fileSize > 0 && (n = dis.read(buf, 0, (int)Math.min(buf.length, fileSize))) != -1)
{
fos.write(buf,0,n);
fileSize -= n;
}
fos.close();
您可以将所有这些内容放在一个循环中,该循环在 readUTF()
throws EOFException
。相反,当然,您必须 writeUTF(filename)
在发送数据之前在发送方 writeLong(filesize)
and