Question

我试图使用Java Web Server但是当我尝试使用浏览器调用例如index.html时，它只告诉我没有数据在chrome中发送。调用不存在的文件会得到所需的响应。有人知道我做错了吗？

package ks.web.server;

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

public final class KSWebServer
{
    public static void main(String argv[]) throws Exception
    {
        //set the port number
        int port = 6789;
        //Establish the listen socket.
        ServerSocket listenSocket = new ServerSocket(6789);
        //Process HTTP service requests in an infinite loop
        while (true)
        {
            //Listen for a TCP connection request
            Socket connectionSocket = listenSocket.accept();

            //Construct an object to process the HTTP request message.
            HttpRequest request = new HttpRequest(connectionSocket);
            // Create a new thread to process the request.
            Thread thread = new Thread(request);
            // Start the thread.
            thread.start();
        }
    }
}
final class HttpRequest implements Runnable
{
    final static String CRLF = "\r\n";
    Socket socket;
    //Constructor
    public HttpRequest(Socket socket) throws Exception
    {
        this.socket = socket;
    }
    // Implement the run() method of the Runnable interface.
    public void run()
    {
        try {
            processRequest();

        } catch (Exception e) {
            System.out.println(e );
            e.printStackTrace();
        }
    }
    private void processRequest() throws Exception
    {
        //Get a reference to the socket's input and output streams.
        InputStream is = socket.getInputStream();
        DataOutputStream os = new DataOutputStream(socket.getOutputStream());
        //Set up input stream filters.
        FilterInputStream fis;
        BufferedReader br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
        //Get the request line of the HTTP request message.
        String requestLine = br.readLine();
        //Display request line.
        System.out.println();
        System.out.println(requestLine);

        // Get and display the header lines
        String headerline = null;
        while ((headerline = br.readLine()).length() != 0)
        {
            System.out.println(headerline);
        }
        //close streams and socket.
        //os.close();
        //br.close();
        //socket.close();   
        // Extract the filename from the request line.
        StringTokenizer tokens = new StringTokenizer(requestLine);
        tokens.nextToken();  // skip over the method, which should be "GET"
        String fileName = tokens.nextToken();
        //Prepend a "." so that file request is within the current directory.
        fileName= "." + fileName;
        // Open the requested file.
        FileInputStream fis1 = null;
        boolean fileExists = true;

        try {
            fis1 = new FileInputStream(fileName);
        }  catch  (FileNotFoundException e) {
            fileExists = false;
        }
        //Construct the response message.
        String statusLine = null;
        String contentTypeLine = null;
        String entityBody = null;

        if(fileExists) {
            statusLine = "Responding to existing file";
            contentTypeLine = "Content-type:" +
                    contentType( fileName ) + CRLF;
        } else {
            statusLine = "File doesn't exist\n";
            contentTypeLine = "no contents\n";
            entityBody = "<HTML>" + "<HEAD><TITLE>Not Found</TITLE></HEAD>" + "<BODY>Not Found</BODY></HTML>";
            // Send the status line.
            os.writeBytes(statusLine);
            // Send the content type line.
            os.writeBytes(contentTypeLine);
            // Send a blank line to indicate the end of the header lines.
            os.writeBytes(CRLF);

            // Send the entity body.

            if (fileExists) {
                sendBytes(fis1, os);
                fis1.close();
            } else {
                os.writeBytes(entityBody);
            }
        }

        os.close();
        br.close();
        socket.close();
    }
    private static void sendBytes(FileInputStream fis, OutputStream os) throws Exception
    {
        // Construct a 1K buffer to hold bytes on their way to the socket.
        byte[] buffer = new byte[1024];
        int bytes = 0;
        // Copy requested file into the socket's output stream.
        while((bytes=fis.read(buffer)) != -1) {
            os.write(buffer, 0, bytes);
        }
    }

    private static String contentType(String fileName)
    {
        if(fileName.endsWith(".htm") || fileName.endsWith(".html")) {
            return "text/html";
        }
        if(fileName.endsWith(".gif") || fileName.endsWith(".GIF"))
        {
            return "image/gif";
        }
        if(fileName.endsWith(".jpeg"))
        {
            return "image/jpeg";
        }
        if(fileName.endsWith(".java"))
        {
            return "java file";
        }
        if(fileName.endsWith(".sh"))
        {
            return "bourne/awk";
        }

        return "application/octet-stream";
    }

}

Answer 1

仔细查看您在if(fileExists) {部分

中的操作

Java Web Server：请求现有文件时不发送数据

1 个答案: