peer-topeer Networks phần 6 ppsx

P1: OTE/SPH P2: OTE

SVNY285-Loo October 18, 2006 7:8

class Share {

private boolean go = true;

boolean debug = false;

int totalProcessor=0;

int doneProcessor=0;

double answer=0.0;

public Share(int totalProcessor,boolean debug)

{

this.debug= debug;

this.totalProcessor = totalProcessor;

}

public synchronized void setGoAhead( )

{

if (debug) System.out.println( Share called go: + go);

while ( !go )

{

try

{

wait();

}

catch ( InterruptedException e )

{

System.err.println( Exception: + e.toString() );

}

}

if (debug) System.out.println( Share setGoAhead go: + go);

go = false;

notifyAll();

}

public synchronized void updateAnswer(double ans)

{

answer =answer+ans;

doneProcessor++;

notifyAll();

}

public synchronized double getAnswer()

{

if (debug) System.out.println(waiting for answer by Server);

while ( doneProcessor != totalProcessor )

{

try

{

wait();

}

catch ( InterruptedException e )

{

System.err.println( Exception: + e.toString() );

}

}

return answer;

}

}

Figure 9.18. share.java

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SVNY285-Loo October 18, 2006 7:8

class ShareObj

{

boolean Done = false;

private int totalProcessor;

private int totalAccess;

private boolean free =true;

boolean debug;

boolean connected=false;

public ShareObj(int i,boolean debug)

{

totalProcessor=i;

this.debug=debug;

totalAccess= 0;

}

public synchronized void increaseConnection()

{

if (debug) System.out.println( Share obj free: + free

+ no. of Processor: +

totalProcessor);

while ( !free )

{

try

{

wait();

}

catch ( InterruptedException e ) {

System.err.println( Exception: + e.toString() );

}

}

free = false;

Done = true;

totalAccess++;

if (totalAccess == totalProcessor)

{

totalAccess =0;

connected=true;

if (debug) System.out.println( Share obj + access:+totalAccess);

}

free = true;

notify();

}

public synchronized void allConnected()

{

while ( !connected)

{

try

{

wait();

}

catch ( InterruptedException e )

{

System.err.println( Exception: + e.toString() );

}

}

}

}

Figure 9.19. shareObj.java

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130 9. Power Server: Model 1

Figure 9.20. Screen of the server in waiting state.

9.3 First Test

You can use only one computer to run your first test. If you are not familiar with

client-server programming, I will recommend you to use one computer for the first

test. A computer can be both server and client concurrently. You must start the

server program first before you run the client program.

1. You start the server program by typing the following command in DOS:

java addServer

The computer will be in a wait state as in Fig. 9.20.

2. Start the client program by typing the following command in anther DOS ses￾sion.

java addClient 1 10 local.txt

The first parameter ‘1’ indicates that there is only one server in the system. The

system will add the number from 1 to 10. There are only 2 lines in the ‘local.txt’ file:

1

localhost

The ‘1’ in the first line indicates there is only one address in the whole file.

‘localhost’ is the synonym of the IP address of your local computer.

The local.txt file enables you to access your own local computer without speci￾fying its IP address. You can see the result in both windows: Fig. 9.21 is the screen

of the server window, while Fig. 9.22 is the screen of the client window.

Figure 9.21. Screen of server window.