/*
* @(#)ChatRoom.java 1.2 95/08/22
*
* Copyright (c) 1995 Sun Microsystems, Inc. All Rights reserved
* Permission to use, copy, modify, and distribute this software
* and its documentation for NON-COMMERCIAL purposes and without
* fee is hereby granted provided that this copyright notice
* appears in all copies. Please refer to the file copyright.html
* for further important copyright and licensing information.
*
* SUN MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF
* THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
* TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE, OR NON-INFRINGEMENT. SUN SHALL NOT BE LIABLE FOR
* ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
* DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES.
*/
package sun.net.www.httpd;
import java.io.*;
import java.util.*;
import sun.net.NetworkServer;
/**
* A class to implement a room in which people can chat.
* @author James Gosling
*/
class ChatRoom {
static final int histlen = 20;
String history[] = new String[histlen];
int histpos = 0;
String name;
PrintStream clients[] = new PrintStream[1];
String clnames[] = new String[1];
private ChatRoom (String n) {
name = n;
}
static Hashtable ht = new Hashtable(20);
static ChatRoom New(String n) {
Object o = ht.get(n);
if (o != null)
return (ChatRoom) o;
ChatRoom ret = new ChatRoom (n);
ht.put(n, ret);
return ret;
}
synchronized void addListener(PrintStream p, String clname) {
int i;
for (i = clients.length; --i >= 0 && clients[i] != null;);
addString(clname + " has just entered the room.\n");
if (i >= 0) {
clients[i] = p;
clnames[i] = clname;
} else {
PrintStream nc[] = new PrintStream[clients.length * 2];
System.arraycopy(clients, 0, nc, 0, clients.length);
String nn[] = new String[nc.length];
System.arraycopy(clnames, 0, nn, 0, clnames.length);
nc[clients.length] = p;
nn[clients.length] = clname;
clients = nc;
clnames = nn;
}
p.print("Welcome to " + name + "\n");
int nseen = 0;
String lastName = null;
for (i = clients.length; --i >= 0;)
if (clients[i] != null && clients[i] != p) {
String n = clnames[i];
if (lastName != null) {
if (nseen > 1)
p.print(", ");
p.print(lastName);
}
lastName = n;
nseen++;
}
if (lastName != null) {
if (nseen > 1)
p.print(" and ");
p.print(lastName);
p.print(nseen > 1 ? " are " : " is ");
p.print("already in the room.\n");
} else
p.print("You are alone in the room.\n");
for (i = history.length; --i >= 0;) {
int slot = histpos - i;
if (slot < 0)
slot += history.length;
if (history[slot] != null) {
p.print(history[slot]);
p.print("\n");
}
}
p.flush();
}
synchronized void removeListener(PrintStream p) {
int i;
int nlisteners = 0;
for (i = clients.length; --i >= 0;)
if (clients[i] == p) {
try {
clients[i].close();
} catch(Exception e);
clients[i] = null;
addString(clnames[i] + " has left the room.\n");
} else if (clients[i] != null)
nlisteners++;
if (nlisteners == 0) {
ht.remove(name);
}
}
synchronized void addString(String s) {
history[histpos] = s;
histpos++;
if (histpos > clients.length)
histpos = 0;
for (int i = clients.length; --i >= 0;)
try {
if (clients[i] != null) {
try {
clients[i].print(s);
clients[i].print("\n");
clients[i].flush();
} catch(Exception e) {
removeListener(clients[i]);
}
}
} catch(Exception e) {
}
}
void converse(NetworkServer ns) {
InputStream in = ns.clientInput;
String clientName = null;
char line[] = new char[1];
try {
while (true) {
int c;
int dp = 0;
while ((c = in.read()) != -1 && c != '\n' && c != '\r') {
if (dp >= line.length) {
char nc[] = new char[line.length * 2];
System.arraycopy(line, 0, nc, 0, line.length);
line = nc;
}
line[dp++] = (char) c;
}
if (c < 0)
break;
if (dp <= 0)
continue;
String s = String.copyValueOf(line, 0, dp);
if (clientName == null) {
clientName = s;
addListener(ns.clientOutput, clientName);
} else {
addString(clientName + ": " + s);
}
}
} catch(Exception e) {
}
removeListener(ns.clientOutput);
}
}