1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/org/sonews/daemon/CommandSelector.java Wed Aug 12 16:43:30 2009 +0200
1.3 @@ -0,0 +1,110 @@
1.4 +/*
1.5 + * SONEWS News Server
1.6 + * see AUTHORS for the list of contributors
1.7 + *
1.8 + * This program is free software: you can redistribute it and/or modify
1.9 + * it under the terms of the GNU General Public License as published by
1.10 + * the Free Software Foundation, either version 3 of the License, or
1.11 + * (at your option) any later version.
1.12 + *
1.13 + * This program is distributed in the hope that it will be useful,
1.14 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
1.15 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1.16 + * GNU General Public License for more details.
1.17 + *
1.18 + * You should have received a copy of the GNU General Public License
1.19 + * along with this program. If not, see <http://www.gnu.org/licenses/>.
1.20 + */
1.21 +
1.22 +package org.sonews.daemon;
1.23 +
1.24 +import java.util.HashMap;
1.25 +import java.util.Map;
1.26 +import java.util.concurrent.ConcurrentHashMap;
1.27 +import org.sonews.daemon.command.Command;
1.28 +import org.sonews.daemon.command.UnsupportedCommand;
1.29 +import org.sonews.util.Log;
1.30 +import org.sonews.util.io.Resource;
1.31 +
1.32 +/**
1.33 + * Selects the correct command processing class.
1.34 + * @author Christian Lins
1.35 + */
1.36 +class CommandSelector
1.37 +{
1.38 +
1.39 + private static Map<Thread, CommandSelector> instances
1.40 + = new ConcurrentHashMap<Thread, CommandSelector>();
1.41 +
1.42 + public static CommandSelector getInstance()
1.43 + {
1.44 + CommandSelector csel = instances.get(Thread.currentThread());
1.45 + if(csel == null)
1.46 + {
1.47 + csel = new CommandSelector();
1.48 + instances.put(Thread.currentThread(), csel);
1.49 + }
1.50 + return csel;
1.51 + }
1.52 +
1.53 + private Map<String, Command> commandMapping = new HashMap<String, Command>();
1.54 + private Command unsupportedCmd = new UnsupportedCommand();
1.55 +
1.56 + private CommandSelector()
1.57 + {
1.58 + String[] classes = Resource.getAsString("helpers/commands.list", true).split("\n");
1.59 + for(String className : classes)
1.60 + {
1.61 + try
1.62 + {
1.63 + Class<?> clazz = Class.forName(className);
1.64 + Command cmd = (Command)clazz.newInstance();
1.65 + String[] cmdStrs = cmd.getSupportedCommandStrings();
1.66 + for(String cmdStr : cmdStrs)
1.67 + {
1.68 + this.commandMapping.put(cmdStr, cmd);
1.69 + }
1.70 + }
1.71 + catch(ClassNotFoundException ex)
1.72 + {
1.73 + Log.msg("Could not load command class: " + ex, false);
1.74 + }
1.75 + catch(InstantiationException ex)
1.76 + {
1.77 + Log.msg("Could not instantiate command class: " + ex, false);
1.78 + }
1.79 + catch(IllegalAccessException ex)
1.80 + {
1.81 + Log.msg("Could not access command class: " + ex, false);
1.82 + }
1.83 + }
1.84 + }
1.85 +
1.86 + public Command get(String commandName)
1.87 + {
1.88 + try
1.89 + {
1.90 + commandName = commandName.toUpperCase();
1.91 + Command cmd = this.commandMapping.get(commandName);
1.92 +
1.93 + if(cmd == null)
1.94 + {
1.95 + return this.unsupportedCmd;
1.96 + }
1.97 + else if(cmd.isStateful())
1.98 + {
1.99 + return cmd.getClass().newInstance();
1.100 + }
1.101 + else
1.102 + {
1.103 + return cmd;
1.104 + }
1.105 + }
1.106 + catch(Exception ex)
1.107 + {
1.108 + ex.printStackTrace();
1.109 + return this.unsupportedCmd;
1.110 + }
1.111 + }
1.112 +
1.113 +}