raplatype.java

Rapla是一个灵活的多用户资源管理系统。它提供的一些功能有：日历GUI

/*--------------------------------------------------------------------------*
 | Copyright (C) 2006 Christopher Kohlhaas                                  |
 |                                                                          |
 | 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. A copy of the license has been included with   |
 | these distribution in the COPYING file, if not go to www.fsf.org         |
 |                                                                          |
 | As a special exception, you are granted the permissions to link this     |
 | program with every library, which license fulfills the Open Source       |
 | Definition as published by the Open Source Initiative (OSI).             |
 *--------------------------------------------------------------------------*/
package org.rapla.entities;

import java.io.Serializable;
import java.lang.reflect.Field;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

import org.rapla.framework.RaplaException;

/**
 * Enumeration Pattern for all Rapla objects. You should not instanciate Objects of this type,
 * there is only one instance of RaplaType for each class of objects. You can get it via
 * the object interface. E.g. Reservation.TYPE or Allocatable.TYPE
 */
public class RaplaType implements Serializable {
    //  Don't forget to increase the serialVersionUID when you change the fields
    private static final long serialVersionUID = 1;

    private String type;
    private String localname;
    private static Map registeredTypes = new HashMap();

    public RaplaType(Class clazz, String localname) {
        this( clazz.getName(), localname);
    }

    protected RaplaType(String name, String localname) {
        this.type = name;
        this.localname = localname;
        if ( registeredTypes == null)
            registeredTypes = new HashMap();
        if ( registeredTypes.get( name ) != null) {
            throw new IllegalStateException( "Type already registered");
        }
        registeredTypes.put( type, this);
    }

    static public RaplaType find( String typeName) throws RaplaException 
    {
        try{
            Class typeClass = Class.forName( typeName );
            Field field = typeClass.getDeclaredField("TYPE");
            RaplaType raplaType = (RaplaType) field.get( null );
            return raplaType;
        } 
        catch (Exception ex)
        {
            throw new RaplaException("Cant find Raplatype for name" + typeName, ex);
        }
    }
    
    public boolean is(RaplaType other) {
        if ( other == null)
            return false;
        return type.equals( other.type);
    }

    public String getLocalName() {
        return localname;
    }

    public String toString() {
        return type;
    }

    /** @deprecated Dangerous to use this method because a class registers itself on load time. 
     * So this method can return different results depending on how much RaplaTypes are currently loaded.*/
    static public Iterator getRegisteredTypes() {
        return registeredTypes.values().iterator();
    }

    public boolean equals( Object other) {
        if ( !(other instanceof RaplaType))
            return false;
        return is( (RaplaType)other);
    }

    public int hashCode() {
        return type.hashCode();
    }
}