Java close TCP/IP connection

Question

I need a java program to download a series of file from a web server and I need to be able to close and then reopen the tcp/ip connection between each file download.

Not sure how to do this.

[What have you tried?](http://mattgemmell.com/2008/12/08/what-have-you-tried/) — Some programmer dude, Mar 29 '12 at 06:04

score 1 · Accepted Answer · edited May 23 '17 at 12:04

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Here is a low-level way of retrieving any information from not only socket 80 (http) but generically to retrieve mail, do a 'telnet' etc:

socket = new Socket();
socket.connect(new InetSocketAddress(host, port));
reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
writer = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));

now to do a call to retrieve a page, send the get command, set the content-type, and send two '\n'.

There is a higher-level solution: Send HTTP GET request with header

edited May 23 '17 at 12:04

Community

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answered Mar 28 '12 at 22:13

SunKing2

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Thanks. That's what I'm looking for. Appreciate the fast response. – BourneAgain Mar 29 '12 at 14:59
Just a follow up question. Once I close the socket and I try to use it again (socket.connect(new InetSocketAddress(host,80));) I receive a java.net.SocketException: Socket is closed error. I can't seem to reopen it. So I am just declaring Socket socket = new Socket();,Socket socket2 = new Socket();, etc... for how many ever files I am getting in the code. Is this the correct way or can I reopen the socket I closed somehow? – BourneAgain Mar 29 '12 at 15:05
It's been awhile since I've coded like this, but from what I remember, the intention of this code was to make a stateless call (ie, get the data, then close the streams and sockets) and end the program (which I left out). To make several http calls, you could create 1. a socket object, and 2. an InetSocketAddress object. Then for each call, just modify the fields of the InetSocketAddress (by calling some set methods on it), create a new reader and writer, get the page, then perform the close statements. – SunKing2 Mar 29 '12 at 22:59
That's what I was thinking also is to just put the socket creation in it own method and call that method for each file GET. Thanks. – BourneAgain Mar 30 '12 at 13:25

score 0 · Answer 2 · answered Mar 28 '12 at 22:11

You can create a Socket for the IP and port you want to send it to, then read the file into a byte array using a FileInputStream and send that byte array through a DataOutPutStream, then when done just flush the dataOutPutStream and close the Socket and call the function again sending the next file.

score 0 · Answer 3 · answered Mar 29 '12 at 08:15

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use the logic: Please post something that you have tried.

 do{
      connection.open;
      while(!eof){
      fetchfiles();
      }
     connection.close;
     }while(no of files yet to download);

answered Mar 29 '12 at 08:15

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Java close TCP/IP connection

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