执行客户端将文件发送到服务器的程序时发生错误

Question

我不知道我在此代码中出错的地方，这些是客户端和服务器程序源代码。首先，我被执行的服务器程序可以很好，但是当我执行客户端程序时，我在侧面(服务器和客户端(上都有错误。新图像(testfile.jpg(也不完整。我将cat.jpg(尺寸1 MB(放在桌面上。

fileclient.java

import java.io.DataOutputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.net.Socket;
public class FileClient {
private Socket s;
public FileClient(String host, int port, String file) {
    try {
        s = new Socket(host, port);
        sendFile(file);
    } catch (Exception e) {
        e.printStackTrace();
    }       
}
public void sendFile(String file) throws IOException {
    DataOutputStream dos = new DataOutputStream(s.getOutputStream());
    FileInputStream fis = new FileInputStream(file);
    byte[] buffer = new byte[4096];
    while (fis.read(buffer) > 0) {
        dos.write(buffer);
    }
    fis.close();
    dos.close();    
}
public static void main(String[] args) {
    FileClient fc = new FileClient("localhost", 1988, "cat.jpg");
}

}

fileserver.java

import java.io.DataInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
public class FileServer extends Thread {
private ServerSocket ss;
public FileServer(int port) {
    try {
        ss = new ServerSocket(port);
    } catch (IOException e) {
        e.printStackTrace();
    }
}
public void run() {
    while (true) {
        try {
            Socket clientSock = ss.accept();
            saveFile(clientSock);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}
private void saveFile(Socket clientSock) throws IOException {
    DataInputStream dis = new DataInputStream(clientSock.getInputStream());
    FileOutputStream fos = new FileOutputStream("testfile.jpg");
    byte[] buffer = new byte[4096];
    int filesize = 15123; // Send file size in separate msg
    int read = 0;
    int totalRead = 0;
    int remaining = filesize;
    while((read = dis.read(buffer, 0, Math.min(buffer.length, remaining))) > 0) {
        totalRead += read;
        remaining -= read;
        System.out.println("read " + totalRead + " bytes.");
        fos.write(buffer, 0, read);
    }
    fos.close();
    dis.close();
}
public static void main(String[] args) {
    FileServer fs = new FileServer(1988);
    fs.start();
}

}

客户端错误

C:UsersvishalDesktop>java FileClient
java.io.FileNotFoundException: cat.jpg (The system cannot find the file 
specified)
    at java.io.FileInputStream.open0(Native Method)
    at java.io.FileInputStream.open(Unknown Source)
    at java.io.FileInputStream.<init>(Unknown Source)
    at java.io.FileInputStream.<init>(Unknown Source)
    at FileClient.sendFile(FileClient.java:23)
    at FileClient.<init>(FileClient.java:15)
    at FileClient.main(FileClient.java:35)

服务器端错误

C:UsersvishalDesktop>java FileServer
java.net.SocketException: Connection reset
    at java.net.SocketInputStream.read(Unknown Source)
    at java.net.SocketInputStream.read(Unknown Source)
    at java.io.DataInputStream.read(Unknown Source)
    at FileServer.saveFile(FileServer.java:39)
    at FileServer.run(FileServer.java:23)

Answer 1

您需要在客户端代码的主要方法中为文件cat.jpg提供正确的路径。

，例如

替换

中的文件名

FileClient fc = new FileClient("localhost", 1988, "cat.jpg");

带有的绝对路径，例如

FileClient fc = new FileClient("localhost", 1988, "c:/user/vishal/desktopcat.jpg");

或诸如

之类的相对路径

FileClient fc = new FileClient("localhost", 1988, "../vishal/desktopcat.jpg");

请注意，根据您执行Java代码的位置，相对路径将很棘手。因此，如果不确定，请使用绝对路径。

解决了此问题后，您的客户端将能够将文件写入套接字，此时您的服务器也将停止抱怨。