Inputstream & outputstreams in network programming

Hi
I have been experimenting with inputstreams & outputstreams through sockets, and have been having some annoying problems.
First off, is it possible to have multiple outputstream types going through the same socket, eg a printwriter to send strings, and an OutputStream to send bytes (files), so that first i can send the file name, then file size, using the writers println methods, then send a byte array via the OutputStreams write method. Do i need to do some clean up etc after each transmission through the socket.
My client is set up to recieve two strings, then a byte array.
Sometimes it works, sometimes it doesnt.
I have even tried setting the buffer sizes of the sockets etc, but still to no success. I think the outputstreams are getting cluttered, but to be honest I dont know. Has anyone successfully and reliably done this type of thing before, if so can you help.
Steve

At least say flush() after having finihhed with one and before turning to the other.

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Network Programming exam papers (college exam papers)

hello.
my name is james mcfadden and i am a final year (4th year) undergraduate computing student at Letterkenny Institute of Technology. my e-mail address is [email protected] I have a question here for you. Would you have links to online versions of final year undergraduate Computing exam papers, specifically Networked Applications Development and or Network Management exam papers? I was only able to get access to Trinity College Dublin�s exam papers and Letterkenny IT�s exam papers.
The 2005/06 academic year is the 1st academic year that final year undergraduate computing students at Letterkenny IT are being taught how to continue doing network programming in Java. i was taught how to do simple network programs in Java when I was in 3rd year.
The name of the network programming subject that I�m doing in 4th year is Network Programming for Broadband Systems. It is divided into 2 parts: Programming and Networks. In past exam papers (C++ papers), a student would have had to answer 4 out of 6 questions. There would�ve been 4 programming questions and 2 networking questions on those papers. It is going to be the same for both the Summer and Autumn 2007 Broadband Network Programming exam papers, apart from fact that they will be Java papers and that a lot of the material that I have learned is new.
In 4th year I did Multicast Sockets, Threads, Non-Blocking I/O, Remote Method Invocation, Protocol Handlers, and Content Handlers for the Programming part of the subject (Java Network Programming, 3rd Edition, by Elliote Rusty Harold).
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I have a question here for you.
Would you have links to online versions of final year
undergraduate Computing exam papers, specifically
Networked Applications Development and or Network
Management exam papers? No

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public String getSeverPort() {
return severPort;
public String getUserName() {
return userName;
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Edited by: 798670 on Sep 29, 2010 6:04 AM

Have you verified that your mysql allows network connections?
In order to allow network connections you have to comment or remove line "skip-networking" in my.ini(windows) or my.cnf(unix) configuration files of your mysql instance.
Or if you have the mysql administrator installed
MySQL Administrator / Startup Variables / Disable networking (uncheck)
By!

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On the java side you use the same Socket and ServerSocket code. On the C side it really depends on which C you are using and which operating system. In VC++ version 5 or 6 you should look at the MS WSA* functions or you could use the socket implementation in MFC. If you using Ansi C on a unix or linux system you can use "berkeley sockets", to get a start check out "man socket".
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http://www.amazon.com/exec/obidos/tg/detail/-/013490012X/104-8001926-7743921?v=glance

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http://java.sun.com/docs/books/tutorial/networking/index.html

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+++++++++++++++++++++++++++++++++++++++++++++++++
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Hey guys it works now - thanks for the byte[] idea..
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Hi,
I m developing a network game , using a multithread
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Peter__Lawrey wrote:
kci wrote:
I am new to network programming can anybody give me some tips on ways to optimize speed of an application that gets data via sockets over the network?Don't worry about it. Your network is much slower than your CPU so it doesn't matter so much what you do in Java.
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Hello
For my socket communications, I am thinking of using InputStream/OutputStream to read/write data. Just realized that InputStream and OutputStream are abstract classes. In particular, the read() and write () are abstract methods
with no actual implementation.
=================================
public abstract int read() throws IOException
Reads the next byte of data from the input stream. The value byte is returned as an int in the range 0 to 255. If no byte is available because the end of the stream has been reached, the value -1 is returned. This method blocks until input data is available, the end of the stream is detected, or an exception is thrown.
A subclass must provide an implementation of this method.
Returns:
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Throws:
IOException - if an I/O error occurs.
============================================
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Thanks for your help,
Alex

Hello
For my socket communications, I am thinking of using
InputStream/OutputStream to read/write data. Just
realized that InputStream and OutputStream are
abstract classes. In particular, the read() and write
() are abstract methods
with no actual implementation.
=================================
public abstract int read() throws IOException
Reads the next byte of data from the input stream. The
value byte is returned as an int in the range 0 to
255. If no byte is available because the end of the
stream has been reached, the value -1 is returned.
This method blocks until input data is available, the
end of the stream is detected, or an exception is
thrown.
A subclass must provide an implementation of this
method.
Returns:
the next byte of data, or -1 if the end of the stream
is reached.
Throws:
IOException - if an I/O error occurs.
============================================
However, when I call these methodes, they actually
work!
What is going on here?There is nothing strange about that. The type of the object that Socket.getInputStream() returns is a subclass of class InputStream. Read a book about Java interfaces and abstract classes (or look it up in the tutorial: http://java.sun.com/docs/books/tutorial/java/index.html).
What is your recommendation for socket I/O? should i
stick with my InputStream/OutputStream, or I should
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Socket s = ...; // create the socket etc.
InputStream sis = s.getInputStream();
DataInputStream dis = new DataInputStream(sis);
// ... now use dis to read dataJesper

Inputstream & outputstreams in network programming

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