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POIs it possible for a server side socket to do both read and write operations on files?
 

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  1. POIs it possible for a server side socket to do both read and write operations on files?
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    <p>Is it possible to do both operations on files in java sockets? If so how? I tried on method in which the client sends a token such as "R" for read and "W" for write and the server examines it and carries out the requested operation. But this does not seem to work. </p> <p>A relevant piece of <strong>client side</strong> code is as follows:</p> <pre><code>public static void readFile(String input, BufferedReader stdin, PrintWriter out, BufferedReader in) throws IOException { System.out.println("Enter the filename that you want to read"); stdin = new BufferedReader(new InputStreamReader(System.in)); String input = stdin.readLine(); out.println("R" + input); System.out.println("File from server \n\n" + in.readLine()); } public static void writeFile(String input, BufferedReader stdin, PrintWriter out, BufferedReader in, Socket s) throws IOException { System.out.println("Enter the filename that you want to write to"); stdin = new BufferedReader(new InputStreamReader(System.in)); input = stdin.readLine(); out.println("W" + " " + input); System.out.println("Enter the text you want to enter in the file"); out.println(stdin.readLine()); System.out.println("File has been updated. The updated file from the server is: " + in.readLine()); } </code></pre> <p>In the <strong>server side</strong>, I've written a code as follows:</p> <pre><code>BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream())); PrintWriter out = new PrintWriter(socket.getOutputStream(),true); String[] recv = in.readLine().split(" "); String file_name = recv[1]; </code></pre> <p>This is the place where I check whether I'm supposed to read or write to the file:</p> <pre><code>if(recv[0] == "R") { while((file_name = recv[1]) != null) { System.out.println("Filename got from client: " + file_name); fileread = new BufferedReader(new FileReader(file_name)); while((line = fileread.readLine()) != null) { out.println(line); } System.out.println("The contents of the file " + file_name + " has been sent to the client"); } } if(recv[0] == "W") { System.out.println("Filename got from client: " + file_name); File file = new File(file_name); filewrite = new FileWriter(file.getAbsoluteFile()); BufferedWriter bw = new BufferedWriter(filewrite); line = in.readLine(); System.out.println(line); bw.write(line); bw.close(); out.println(line); System.out.println("The contents of the file " + file_name + " has been sent to the client"); } } </code></pre> <p>I do not get an explicit error, but when I run the program, the client takes the file name, the server recognizes it (I know this as I make the server print the name of the file), and then the server does nothing; it stops (without any errors or exceptions). </p> <p>Can anyone tell me where I went wrong? Or is there a better method to carry out the task?</p> <p>Thanks in advance.</p>
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    1. USMaddy
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    1. CO`ServerSocket` doesn't read or write anything, and neither `ServerSocket` nor `Socket` does anything to files. Your question doesn't make sense. Try again.
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      1. POIs it possible for a server side socket to do both read and write operations on files?
      1. USuser207421
 

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