java - 文件传输但无法在其各自的启动器中加载(Adobe Pdf) - Java 服务器客户端

Question

我有一个为我的 Java 类工作的项目，我正在使用套接字是的，我查看在线教程寻求帮​​助，目的是读取 pdf 类型的服务器上的文件，然后允许客户端从断绝。

我的问题它请求文件，但在请求文件并将其存储在客户端计算机上后，当我点击要启动的文件时，adobe 说文件“Adobe 无法打开该文件，因为它不是受支持的文件类型，或者因为文件已损坏

这是我的代码，如果有人可以帮助我，我将不胜感激:

服务器代码:

import java.io.*;
import java.net.*;

public class SimpleFileServer {

 public final static String FILE_TO_SEND = "‪c:/Users/Acer/Downloads/COAFlags.pdf"; // you may change this

public static void main(String args[]) {

    while (true) {
        ServerSocket welcomeSocket = null;
        Socket connectionSocket = null;
        BufferedOutputStream outToClient = null;

        try {
            welcomeSocket = new ServerSocket(3248);
            connectionSocket = welcomeSocket.accept();
            outToClient = new BufferedOutputStream(connectionSocket.getOutputStream());
        } catch (IOException ex) {
            // Do exception handling
        }

        if (outToClient != null) {
            File myFile = new File( FILE_TO_SEND);
            byte[] mybytearray = new byte[(int)myFile.length()];

            FileInputStream fis = null;

            try {
                fis = new FileInputStream(myFile);
            } catch (FileNotFoundException ex) {
                // Do exception handling
            }
            BufferedInputStream bis = new BufferedInputStream(fis);

            try {
                bis.read(mybytearray, 0, mybytearray.length);
                outToClient.write(mybytearray, 0, mybytearray.length);
                outToClient.flush();
                outToClient.close();
                connectionSocket.close();

                // File sent, exit the main method
                return;
            } catch (IOException ex) {
                // Do exception handling
            }
        }
    }
}}

客户端

import java.io.*;
import java.io.ByteArrayOutputStream;
import java.net.*;

public class SimpleFileClient {

private final static String serverIP = "localhost";
public final static int FILE_SIZE = 55000;
private final static int serverPort = 3248;
private final static String fileOutput = "c:/Users/Acer/Downloads/sourcedownloaded.pdf";

public static void main(String args[]) {
    byte[] aByte = new byte[FILE_SIZE];
    int bytesRead;

    Socket clientSocket = null;
    InputStream is = null;

    try {
        clientSocket = new Socket( serverIP , serverPort );
        is = clientSocket.getInputStream();
    } catch (IOException ex) {
        // Do exception handling
    }

    ByteArrayOutputStream baos = new ByteArrayOutputStream();

    if (is != null) {

        FileOutputStream fos = null;
        BufferedOutputStream bos = null;
        try {
            fos = new FileOutputStream( fileOutput );
            bos = new BufferedOutputStream(fos);
            bytesRead = is.read(aByte, 0, aByte.length);

            do {
                    baos.write(aByte);
                    bytesRead = is.read(aByte);
            } while (bytesRead != -1);

            bos.write(baos.toByteArray());
            bos.flush();
            bos.close();
            clientSocket.close();
        } catch (IOException ex) {
            // Do exception handling
        }
    }
}}

我想要传输的文件是 54KB，所以它没有超出范围。

Answer 1

这不是你应该做的事。您必须在 while 循环内传输文件，因此您使用的缓冲区不会使用太多内存。服务器端:

ServerSocket socket = new ServerSocket();
socket.bind(new InetSocketAddress("127.0.0.1",9200));
while(true) //that loop provides server non-stop sending, it will response to client requests till you terminate the application.
{
    Socket received = socket.accept();
    FileInputStream input = new FileInputStream("c:/Users/Acer/Downloads/COAFlags.pdf");
    OutputStream output = received.getOutputStream();
    int length;
    byte[] buffer = new byte[4096];

    while((length = input.read(buffer)) != -1)
    {
        output.write(buffer, 0, length);
    }

    output.close(); //no need to flush because close() already does it
    input.close();
}

客户端:

Socket socket = new Socket("127.0.0.1", 9200);
InputStream input = socket.getInputStream();
FileOutputStream output = new FileOutputStream("c:/Users/Acer/Desktop/abc.pdf");
int length;
byte[] buffer = new byte[4096];

while((length = input.read(buffer)) != -1)
{
    output.write(buffer, 0, length);
}

output.close();
input.close();

注意:缓冲区大小是可选的。一般使用4096。