modelserverproxy.java

这是一个以JAVA编写的程序,本人还没有试过,是一个简单的温度控制系统

package net.sf.dz.view.tcp.server;

import java.io.PrintWriter;
import java.util.Iterator;
import java.util.HashMap;
import java.util.Map;
import java.util.StringTokenizer;

import org.freehold.jukebox.logger.LogAware;
import org.freehold.jukebox.logger.Logger;

import net.sf.dz.Model;
import net.sf.dz.device.model.Unit;

/**
 * Server side model proxy.
 *
 * <p>
 *
 * The whole <code>*Proxy</code> hierarchy is not the most efficient nor
 * elegant way to do the job, however, since the entry points and interfaces
 * are well defined, it doesn't really matter as long as it does its job,
 * which is to enable the remote access to the {@link net.sf.dz.Model model}
 * without a heavy overhead of things like EJB. The overhead cannot be
 * tolerated because the model may be run on the hardware platforms with
 * memory and/or performance limitations, such as <a
 * href="http://www.ibutton.com/TINI/index.html" target="_top">TINI</a>. For
 * the same reason, the code better be compliant with the lowest possible
 * version of JDK - for example, TINI offers JDK 1.1 compliance - no
 * serialization, no reflection. As soon as first limitation is lifted, it
 * would be possible to implement the {@link net.sf.dz.view.tcp.Message
 * Message} using serialization, with the disappearance of the second it may
 * make sense to use the <code>java.lang.reflect.Proxy</code>, but this is
 * all in the future. Welcome to the stone age.
 *
 * @author Copyright &copy; <a href="mailto:[e-mail]">Vadim Tkachenko</a> 2001-2002
 * @version $Id: ModelServerProxy.java,v 1.4 2002/08/06 04:33:26 vtt Exp $
 */
public class ModelServerProxy extends AbstractServerProxy implements Model {

    private Model model;
    
    /**
     * Unit map.
     *
     * The key is the proxy, the value is the unit object.
     */
    private Map unitMap = new HashMap();
    
    public ModelServerProxy(Logger logger, Model model) {
    
        super(logger);
    
        // VT: FIXME: Check for the argument sanity
        
        this.model = model;
        
        for ( Iterator i = model.iterator(); i.hasNext(); ) {
        
            Unit unit = (Unit)i.next();
            Unit proxy = new UnitServerProxy(logger, unit);
            
            unitMap.put(proxy, unit);
        }
    }
    
    public Iterator iterator() {
    
        return unitMap.keySet().iterator();
    }
    
    /**
     * Render the model reflection.
     *
     * The reflection is rendered as XML object. The empty line is a
     * terminator.
     *
     * @param pw The print writer to render the model onto.
     */
    public synchronized void renderReflection(PrintWriter pw) {
    
        pw.println("<model>");
        
        for ( Iterator i = unitMap.keySet().iterator(); i.hasNext(); ) {
        
            ((UnitServerProxy)i.next()).renderReflection(pw);
        }
        
        pw.println("</model>");
        pw.println("");
        pw.flush();
    
    }
    
    public void dumpState(PrintWriter pw) {
    
        for ( Iterator i = unitMap.keySet().iterator(); i.hasNext(); ) {
        
            ((UnitServerProxy)i.next()).dumpState(pw);
        }
        
        pw.flush();
    }
    
    public void listen(PrintWriter pw) {
    
        super.listen(pw);
    
        for ( Iterator i = unitMap.keySet().iterator(); i.hasNext(); ) {
        
            ((UnitServerProxy)i.next()).listen(pw);
        }
    }
    
    public void parse(String command) throws Throwable {
    
        StringTokenizer st = new StringTokenizer(command, ":");
        String target = st.nextToken();
        
        if ( "unit".equals(target) ) {
        
            String unitName = st.nextToken();
        
            for ( Iterator i = unitMap.keySet().iterator(); i.hasNext(); ) {
            
                UnitServerProxy unitProxy = (UnitServerProxy)i.next();
                
                if ( unitProxy.getName().equals(unitName) ) {
                
                    unitProxy.parse(st);
                    return;
                }
            
            }
            
            throw new IllegalArgumentException("Unknown unit name '" + unitName + "'");
        
        } else {
        
            throw new IllegalArgumentException("Unknown target: '" + target + "'");
        }
    }
}