omcomponent.java

openmap java写的开源数字地图程序. 用applet实现,可以像google map 那样放大缩小地图.

// **********************************************************************
// 
// <copyright>
// 
//  BBN Technologies
//  10 Moulton Street
//  Cambridge, MA 02138
//  [phone]
// 
//  Copyright (C) BBNT Solutions LLC. All rights reserved.
// 
// </copyright>
// **********************************************************************
// 
// $Source: /cvs/distapps/openmap/src/openmap/com/bbn/openmap/OMComponent.java,v $
// $RCSfile: OMComponent.java,v $
// $Revision: 1.5.2.2 $
// $Date: 2004/10/14 18:26:38 $
// $Author: dietrick $
// 
// **********************************************************************

package com.bbn.openmap;

import java.util.Properties;

/**
 * A OMComponent is an OpenMap component that does two basic things:
 * it is a MapHandlerChilds, so it knows how to use the MapHandler to
 * find other components it needs, and it is a PropertyConsumer, so it
 * can be configured by a set of Properties. An OMComponent is a
 * perfect candidate to be created by being listed in the
 * openmap.components property of the openmap.properties file.
 */
public class OMComponent extends MapHandlerChild implements PropertyConsumer {

    /**
     * All OMComponents have access to an I18n object, which is
     * provided by the Environment.
     */
    protected I18n i18n = Environment.getI18n();

    /**
     * Token uniquely identifying this component in the application
     * properties.
     */
    protected String propertyPrefix = null;

    /**
     * Sets the properties for the OMComponent.
     * 
     * @param props the <code>Properties</code> object.
     */
    public void setProperties(java.util.Properties props) {
        setProperties(getPropertyPrefix(), props);
    }

    /**
     * Sets the properties for the OMComponent.
     * 
     * @param prefix the token to prefix the property names
     * @param props the <code>Properties</code> object
     */
    public void setProperties(String prefix, java.util.Properties props) {
        setPropertyPrefix(prefix);

        // In a subclass, you can use this to get "" if the prefix
        // isn't defined, or "prefix." if it is. Either way, you can
        // then append the realPrefix with wild abandon...
        //      String realPrefix =
        // PropUtils.getScopedPropertyPrefix(prefix);
    }

    /**
     * PropertyConsumer method, to fill in a Properties object,
     * reflecting the current values of the OMComponent. If the
     * component has a propertyPrefix set, the property keys should
     * have that prefix plus a separating '.' prepended to each
     * propery key it uses for configuration.
     * 
     * @param props a Properties object to load the PropertyConsumer
     *        properties into. If props equals null, then a new
     *        Properties object should be created.
     * @return Properties object containing PropertyConsumer property
     *         values. If getList was not null, this should equal
     *         getList. Otherwise, it should be the Properties object
     *         created by the PropertyConsumer.
     */
    public Properties getProperties(Properties props) {
        if (props == null) {
            props = new Properties();
        }

        //      String prefix = PropUtils.getScopedPropertyPrefix(this);

        return props;
    }

    /**
     * Method to fill in a Properties object with values reflecting
     * the properties able to be set on this PropertyConsumer. The key
     * for each property should be the raw property name (without a
     * prefix) with a value that is a String that describes what the
     * property key represents, along with any other information about
     * the property that would be helpful (range, default value,
     * etc.). For Layer, this method should at least return the
     * 'prettyName' property.
     * 
     * @param list a Properties object to load the PropertyConsumer
     *        properties into. If getList equals null, then a new
     *        Properties object should be created.
     * @return Properties object containing PropertyConsumer property
     *         values. If getList was not null, this should equal
     *         getList. Otherwise, it should be the Properties object
     *         created by the PropertyConsumer.
     */
    public Properties getPropertyInfo(Properties list) {
        if (list == null) {
            list = new Properties();
        }
        return list;
    }

    /**
     * Set the property key prefix that should be used by the
     * PropertyConsumer. The prefix, along with a '.', should be
     * prepended to the property keys known by the PropertyConsumer.
     * 
     * @param prefix the prefix String.
     */
    public void setPropertyPrefix(String prefix) {
        propertyPrefix = prefix;
    }

    /**
     * Get the property key prefix that is being used to prepend to
     * the property keys for Properties lookups.
     * 
     * @return the property prefix string
     */
    public String getPropertyPrefix() {
        return propertyPrefix;
    }
}