configscheme.java

java 开发的一个电子邮局,挺实用的

/* $Id: ConfigScheme.java,v 1.4 2000/09/13 10:34:05 wastl Exp $ */
package net.wastl.webmail.config;

import java.util.*;

/*
 * ConfigScheme.java
 *
 * Created: 31.08.99
 *
 * Copyright (C) 1999-2000 Sebastian Schaffert
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */
/**
 * This class contains a scheme for WebMail configuration data.
 *
 * It is mainly a container for the ConfigParameter objects and a wrapper to access
 * the main functions in them to ease access to the scheme.
 *
 * Created: 31.08.99
 *
 * @author Sebastian Schaffert
 * @version $Revision: 1.4 $
 */
public class ConfigScheme {
    
    protected Hashtable config_scheme;

    public ConfigScheme() {
	System.err.print("- Configuration Scheme Handler ... ");
	config_scheme=new Hashtable();
	System.err.println("done!");
    }

    /**
     * Check whether a key/value pair is valid in this configuration scheme
     * @param key Name of the parameter
     * @param value value to check for
     */
    public boolean isValid(String key, Object value) {
	ConfigParameter scheme=getConfigParameter(key);
	if(scheme==null) {
	    return false;
	} else {
	    return scheme.isPossibleValue(value);
	}
    }

    public String filter(String key, String value) {
	ConfigParameter c=(ConfigParameter)config_scheme.get(key);
	if(c!=null) {
	    return c.filter(value);
	} else {
	    return value;
	}
    }

    /**
     * Register a configuration key that can take String values
     * @param key Name of the configuration key
     * @param default Default value for this key
     * @param desc Description for this key
     */
    public void configRegisterStringKey(String key, String def, String desc) {
	StringConfigParameter parm=new StringConfigParameter(key,def,desc);
	registerConfig(parm);
    }

    public void configRegisterStringKey(ConfigurationListener l,String key, String def, String desc) {
	StringConfigParameter parm=new StringConfigParameter(key,def,desc);
	registerConfig(parm);
	parm.addConfigurationListener(l);
    }

    /**
     * Register a configuration key that can take String values
     * @param key Name of the configuration key
     * @param default Default value for this key
     * @param desc Description for this key
     */
    public void configRegisterIntegerKey(String key, String def, String desc) {
	IntegerConfigParameter parm=new IntegerConfigParameter(key,def,desc);
	registerConfig(parm);
    }

    public void configRegisterIntegerKey(ConfigurationListener l,String key, String def, String desc) {
	IntegerConfigParameter parm=new IntegerConfigParameter(key,def,desc);
	registerConfig(parm);
	parm.addConfigurationListener(l);
    }

    /**
     * Register a configuration key that can take String values and crypts them
     * @param key Name of the configuration key
     * @param default Default value for this key
     * @param desc Description for this key
     */
    public void configRegisterCryptedStringKey(String key, String def, String desc) {
	CryptedStringConfigParameter parm=new CryptedStringConfigParameter(key,def,desc);
	registerConfig(parm);
    }

    public void configRegisterCryptedStringKey(ConfigurationListener l,String key, String def, String desc) {
	CryptedStringConfigParameter parm=new CryptedStringConfigParameter(key,def,desc);
	registerConfig(parm);
	parm.addConfigurationListener(l);
    }

    /**
     * Register a configuration key that can take one of a choice of possible values
     * @param key Name of the configuration key
     * @param desc Description for this key
     * @see configAddChoice
     */
    public void configRegisterChoiceKey(String key, String desc) {
	ChoiceConfigParameter parm=new ChoiceConfigParameter(key,desc);
	registerConfig(parm);
    }

    public void configRegisterChoiceKey(ConfigurationListener l,String key, String desc) {
	ChoiceConfigParameter parm=new ChoiceConfigParameter(key,desc);
	registerConfig(parm);
	parm.addConfigurationListener(l);
    }

    public void configRegisterYesNoKey(String key, String desc) {
	ChoiceConfigParameter parm=new ConfigYesNoParameter(key,desc);
	registerConfig(parm);
    }

    public void configRegisterYesNoKey(ConfigurationListener l,String key, String desc) {
	ChoiceConfigParameter parm=new ConfigYesNoParameter(key,desc);
	registerConfig(parm);
	parm.addConfigurationListener(l);
    }

    /**
     * Add a choice to an already-existing Choice-key
     * @param key Name of the configuration key where a choice is to be added
     * @param choice Name of the new choice
     * @param desc Description for this choice
     */
    public void configAddChoice(String key, String choice, String desc) {
	if(config_scheme!=null) {
	    ConfigParameter parm=(ConfigParameter)config_scheme.get(key);
	    if(parm instanceof ChoiceConfigParameter) {
		((ChoiceConfigParameter)parm).addChoice(choice,desc);
	    }
	}
    }

    /**
     * Add a configuration listener for a key.
     * There may be any amount of Listeners for a parameter.
     */
    public void addConfigurationListener(String key,ConfigurationListener l) {
	ConfigParameter parm=getConfigParameter(key);
	parm.addConfigurationListener(l);
    }	

    public ConfigParameter getConfigParameter(String key) {
	return (ConfigParameter)config_scheme.get(key);
    }

    public String getConfigParameterType(String key) {
	return getConfigParameter(key).getType();
    }

    public String getConfigParameterGroup(String key) {
	return getConfigParameter(key).getGroup();
    }

    public Object getDefaultValue(String key) {
	ConfigParameter cp=(ConfigParameter)config_scheme.get(key);
	if(cp!=null) {
	    return cp.getDefault();
	} else {
	    return null;
	}
    }

    public void setDefaultValue(String key, Object default_value) {
	ConfigParameter cp=(ConfigParameter)config_scheme.get(key);
	if(cp!=null) {
	    cp.setDefault(default_value);
	}
    }
       

    public String getDescription(String key) {
	ConfigParameter cp=(ConfigParameter)config_scheme.get(key);
	if(cp!=null) {
	    return cp.getDescription();
	} else {
	    return null;
	}
    }

    public Enumeration getPossibleKeys() {
	return config_scheme.keys();
    }

    public void notifyConfigurationChange(String key) {
// 	System.err.println("NOTIFY: "+key);
	ConfigParameter parm=getConfigParameter(key);
	if(parm!=null) {
	    Enumeration enum=parm.getConfigurationListeners();
	
	    while(enum.hasMoreElements()) {
		ConfigurationListener l=(ConfigurationListener)enum.nextElement();
// 		System.err.println(l);
		try {
		    l.notifyConfigurationChange(key);
		} catch(Exception e) {
		    e.printStackTrace();
		}
	    }
	}
    }

    public void registerConfig(ConfigParameter parm) {
	if(config_scheme == null) {
	    config_scheme=new Hashtable();
	}
	Enumeration e=config_scheme.keys();
	boolean flag=false;
	while(e.hasMoreElements()) {
	    if(e.nextElement().equals(parm.getKey())) {
		flag=true;
		break;
	    }
	}
	if(!flag) {
	    config_scheme.put(parm.getKey(),parm);
	}
    }
}