Java TCP Socket send byte array

Question

I'm trying to build a file server using Java TCP sockets. I keep getting an error when I try to send a file over a few KB. The error is as follows:

Exception in thread "main" java.net.SocketException: Connection reset by peer: socket write error
at java.net.SocketOutputStream.socketWrite0(Native Method)
at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:92)
at java.net.SocketOutputStream.write(SocketOutputStream.java:136)
at fileServer.TCPServer.main(TCPServer.java:193)

I am creating the output stream like this:

OutputStream output = clientSocket.getOutputStream()

And the error originates from this line: output.write(sendData, 0, sendData.length)

Where sendData is a byte array I hand make to an agreed upon 'protocol' that is 28 header bytes along with the file. The file it is erroring out on is about 780kB where a 2kB file works perfect. Any ideas?

EDIT: some added context of how I'm making the socket.

            Socket clientSocket = listenSocket.accept();
        System.out.println("server is listening...");

        DataInputStream input = new DataInputStream(clientSocket.getInputStream());
        OutputStream output = clientSocket.getOutputStream();



        //receive the request packet
        //int nb = input.readInt();
        System.out.println("Read Length " + "28");
        byte[] sentence = new byte[28];
        for(int i=0; i<28; i++){
            sentence[i] = input.readByte();
        }

And this is how I'm sending the data: sendData is the bytearray I built to send tArray is the array of bytes of the file that I'm coping into sendData to send

for(int i = 0; i<filSize; i++){
   //loads into the packet being built
   //needed to minus 36 since all the header info
   endData[i+36] = tArray[i];
}
System.out.println("send packet size: " + sendData.length);

System.out.print(sendData);
System.out.println("File size is: " + filSize);
int sendDataLength = sendData.length;
try{
    output.write(sendData, 0, sendDataLength);
}catch (IOException e){
    System.out.println("Error: " + e.getMessage());
}
clientSocket.close();

EDIT 2: I used a try catch and got this error now: Software caused connection abort: socket write error

Femi · Accepted Answer · 2011-05-10 04:18:16Z

2

Socket reset by peer means the other end disconnected incorrectly. Check that your client is correctly keeping the socket open.

EDIT: assuming you are using code that looks like this, you shouldn't be using a DataInputStream. If you want to use readByte to receive the data you must use writeByte on the sending side. Your socket reset is probably occuring because the readByte call is not getting SOMETHING it expects. Don't use a DataInputStream: use a BufferedInputStream and use the read method.

edited May 10, 2011 at 4:18

answered May 10, 2011 at 3:49

Femi

64.8k8 gold badges120 silver badges150 bronze badges

Sign up to request clarification or add additional context in comments.

8 Comments

kjkurtz Over a year ago

Using 2 different clients in 2 different languages I still get the error. The biggest file I've gotten to work without the error so far is 12kB.

Femi Over a year ago

Well, you might be making the same error in both clients. Are you reading the incoming data correctly in both clients? It'll be hard to decipher without any code.

kjkurtz Over a year ago

I added some more server side code but I don't have access to the client code at the moment. I'll grab it off the other computer if you don't see anything wrong with what I have shown for the server so far.

davmac Over a year ago

@Fermi, readByte() can't get something that it doesn't expect - it reads a byte from the stream. It certainly can't directly cause the remote end to issue a disconnect. Depending on how the client is sending data, using a DataInputStream might be a perfectly good solution here.

Femi Over a year ago

@davmac: see download.oracle.com/javase/6/docs/api/java/io/…. It notes See the general contract of the readByte method of DataInput.. If you look at DataInput (at download.oracle.com/javase/6/docs/api/java/io/…) it says This method is suitable for reading the byte written by the writeByte method of interface DataOutput. I'm uncertain if DataOutput's writeByte produces data that is identical to a standard OutputStream's write.

|

Community · Accepted Answer · 2017-05-23 11:50:53Z

0

I have also googled for similar problems.

One of the rarely mentioned reason is about the cache issue on the browser. Some browsers will reset connections due to some unexpected cache logics.

To solve it, use this line of code in the beginning of your servlet.

response.addHeader("Cache-Control", "no-transform, max-age=0");

I got this answer from Servlet to load video file from server . This may not be 100% the same cause of your problems, but worth a try.

edited May 23, 2017 at 11:50

CommunityBot

11 silver badge

answered Jul 5, 2013 at 9:27

sken130

3602 silver badges13 bronze badges

Collectives™ on Stack Overflow

Java TCP Socket send byte array

2 Answers 2

8 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

8 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related