[es] - problem sa serijalizacijom

range
Beograd

Član broj: 1006
Poruke: 248
*.net.yu

+1 Profil

^{18.06.2002. u 11:26 - pre 265 meseci}

Imam klijenta koji salje objekat Konto serveru, koji ga deserijalizuje i
smesta u bazu. Klijent ima metode listenSocket(), kojim otvara Socket na
nekom portu, i metod sendKonto koji za parametre ima socket preko koga se
salje i objekat Konto koji se salje. Server ima isto metod listenSocket()
koji ima while(true) petlju u kojoj osluskuje klijente, deserijalizuje
objekte, i smesta podatke u bazu.Problem je u sledecem: samo jednaput ja
mogu da unesem podatke u bazu, posle tog jednog puta server pada uz
exception java.net.SocketException: Socket is closed, a ja stvarno nigde ne
zatvaram socket.Jel zna neko sta bi to moglo da bude?
Evo koda:
klijent :

public void listenSocket(){
ObjectOutputStream outputKonto = null;

socket = new Socket("HOST-NAME", 4444);
in = new BufferedReader(new
InputStreamReader(socket.getInputStream()));
outputKonto = new ObjectOutputStream(socket.getOutputStream());
System.out.println("Connected!!!!!!! ");
}
catch (UnknownHostException e) {
System.out.println("Unknown host: ");
System.exit(1);
}
catch (IOException e) {
System.out.println("No I/O");
e.printStackTrace();
System.exit(1);
}
}
protected void sendKontoToServer(){
theKonto = this.getKonto1();
try{
socket = this.getSocket();
sendKonto(socket, theKonto);
}
catch (Exception e) {
System.out.println("Unknown host: ");
e.printStackTrace();
System.exit(1);
}

}

protected void sendKonto(Socket socket, Konto theKonto){
ObjectOutputStream outputToServer = null;
try{
outputToServer = new ObjectOutputStream(socket.getOutputStream());
outputToServer.writeObject(theKonto);
outputToServer.flush();
outputToServer.close();

}
catch (IOException e){
e.printStackTrace();
}
}
server:
public void listenSocket(){
ObjectInputStream inputKonto = null;
Konto aKonto = null;
try{
server = new ServerSocket(4444);
client = server.accept();
System.out.println("Opened socket!");
}
catch(IOException ioE){
System.out.println("Could not listen on port 4444");
ioE.printStackTrace();
System.exit(-1);
}
try{
System.out.println("3");
inputKonto = new ObjectInputStream(client.getInputStream());
out = new PrintWriter(client.getOutputStream(), true);
}
catch(IOException ioE){
System.out.println("Accepting connection on port 4444failed!2");
ioE.printStackTrace();
System.exit(-1);
}
while(true){
try{
inputKonto = new ObjectInputStream(client.getInputStream());
out = new PrintWriter(client.getOutputStream(), true);
aKonto = (Konto)inputKonto.readObject();
inputKonto.close();
access.insertKonto(aKonto);

}
catch(Exception E){
System.out.println("Reading failed!" + E.getMessage());
E.printStackTrace();
System.exit(-1);
}
}
}

Odgovor na temu

weB_KiLeR

Član broj: 238
Poruke: 1317
*.041net.co.yu

Profil

Re: problem sa serijalizacijom

^{18.06.2002. u 18:01 - pre 265 meseci}

Pazi postoji dosta problema zasto bi pucala veza na serveru...
Probaj da uradis u odvojenim thread-ovima komuniciranje client-server ako client ima user interface moras da mu ubacis thread-ove jer ako to nemas onda sve ode u k...
Tj ili pukne server ili client skroz usmercuje ...
Baci mi source celog progyja pa cu da probam da ga nateram da radi...
E da evo ti jedan kod koji bi mogao da ti pomogne...

Citat:

import java.net.*;
import java.io.*;
import java.util.Vector;
import java.util.Enumeration;

public class Server {

Vector knjiga;
ServerSocket s;
Socket cSocket;
File database;
int port;

public static void main(String[] args) throws IOException
{
Server myServer = new Server(1234);
while (true) {
myServer.getClientConnection();
}
}

private void saveDB() throws IOException
{
PrintWriter DBWriter = new PrintWriter(new BufferedWriter(new FileWriter(database)));
for (Enumeration e = AddressBook.elements(); e.hasMoreElements();) {
DBWriter.println((String)e.nextElement());
}
DBWriter.close();
}

private String processCommand (String commandLine) throws IOException
{
String command = null;
String argument = null;
String record;
String output="";
int space;

//client's command parsing
commandLine = commandLine.trim();
commandLine = commandLine.toUpperCase();
if ((space = commandLine.indexOf(' '))==-1)
command=commandLine;
else {
command = commandLine.substring (0,space);
argument = commandLine.substring (space, commandLine.length()).trim();
}

if (command.equals("LIST")) {
output = "\nListing records:\n";
for (Enumeration e = knjiga.elements(); e.hasMoreElements();)
output = output + (String)e.nextElement() + '\n';
output = output + "\n\t"+ knjiga.size() + " element(s) found\n";
}
else if (command.equals("SEARCH")) {
int count = 0;
output = "\nSearching for \"" + argument + "\".\n";
for (Enumeration e = knjiga.elements(); e.hasMoreElements();) {
record = (String)e.nextElement();
if (record.toUpperCase().indexOf(argument)!=-1) {
output = output + record + '\n';
count++;
}
}
output = output + "\n\t"+ count + " element(s) found\n";
}
else if (command.equals("STORE")) {
knjiga.addElement(argument);
output = "\nRecord added: " + argument + "\n";
}
else if (command.equals("SAVE")) {
saveDB();
output = "\nAddress Book saved\n";
}
else output = "\nUnknown command\n";
return output;
}

private void getClientConnection ()
{
String command = null;
PrintWriter out = null;
BufferedReader in = null;

try {
// Waits for clients' connection requests
cSocket = sSocket.accept();

// Gets input/output streams
out = new PrintWriter(cSocket.getOutputStream(), true);
in = new BufferedReader(new InputStreamReader(cSocket.getInputStream()));

// Hello client
out.println ("\nWelcome to AddressBook network application.");

// Waits for client's command
while ((command = in.readLine()) != null) {

//if client says "Bye" the connection is closed
if (command.equals("bye")) {
out.println ("Have a nice time.\n");
// Closes the connection
out.close();
in.close();
cSocket.close();
return;
}

// Answers to client command
out.println (processCommand (command));
}

} catch (IOException e) {
System.err.println("Client connection closed.");
return;
}

}

public Server (int port)
{
AddressBook = new Vector(50,25);
sSocket = null;
cSocket = null;
this.port=port;
DBFile = new File ("abook.dat");

// Reads records form file add fills in AddressBook
// If no database file esists creates a new one
try {
if (DBFile.exists()) {
BufferedReader fileReader = null;
String record = null;
fileReader = new BufferedReader(new FileReader(DBFile));
while ((record = fileReader.readLine()) != null)
AddressBook.addElement(record);
fileReader.close();
} else {
PrintWriter newDBFile = new PrintWriter(new BufferedWriter(new FileWriter(DBFile)));
newDBFile.close();
}
} catch (FileNotFoundException e) {
System.exit(1);
} catch (IOException e) {
System.err.println ("Errore nell'apertura del file archivio");
System.exit(1);
}

// Initialise ServerSocket
try {
sSocket = new ServerSocket(port);
} catch (IOException e) {
System.err.println("Cannot listen on port: " + String.valueOf(port));
System.exit(1);
}

}
}

O thread-ovima mozes naci na adresi
http://www.javaworld.com/javaw...-05-2002/jw-0503-java101.html?
Ovde imas jedan mali tutorial o tome ako jos imas problema mogu ti dati moje projekte gde to imas...

Odgovor na temu

range
Beograd

Član broj: 1006
Poruke: 248
*.dial.InfoSky.Net

+1 Profil

Re: problem sa serijalizacijom

^{18.06.2002. u 21:28 - pre 265 meseci}

Hvala ti na odgovoru, i bio si totalno upravu. Samo sto sam ja to otkrio koji sat pre tvog posta, ali u svakom slucaju hvala ti. Za pocetak sam hteo da mi ova aplikacija radi za single usera, pa i nisam hteo da mi server extends Thread ili implements Runnable. Medjutim cim sam uterao Server u thread stvar je proradila. Stvar je u tome sto threadovi su mi stvar sama po sebi za izbegavanje i to u sirokom luku, izmedju ostalog zato sto jedini projekat koji nisam zavrsio bio u vezi sa njima (chat koji je trebao da podrzi ICQ, Messangera i Jabbera). Ako te interesuje mogu da ti posaljem kod da vidis kako izgleda sada.
pozdrav Sreten
ps. Ovo je ona aplikacija za racunovodstvo i videcemo koliko su sve neverne tome ovde bili u pravu kada su pricali da je java nezgodna za to

Odgovor na temu