librarybean.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/layer/vpf/LibraryBean.java,v $
// $RCSfile: LibraryBean.java,v $
// $Revision: 1.4.2.3 $
// $Date: 2004/10/14 18:27:21 $
// $Author: dietrick $
// 
// **********************************************************************

package com.bbn.openmap.layer.vpf;

import java.io.Serializable;
import java.util.*;

import com.bbn.openmap.util.Debug;
import com.bbn.openmap.util.PropUtils;
import com.bbn.openmap.PropertyConsumer;

/**
 * A bean to be used for sharing LibrarySelectionTable objects between
 * instances of VPFLayer.
 * 
 * <pre>
 * 
 * # Assuming that you have a VPF Layer specifying a .libraryBean property
 * # with a value of &quot;VMAPData&quot;, you need to specify the following properties:
 * # Required - the java class information
 * VMAPData.class=com.bbn.openmap.layer.vpf.LibraryBean
 * # as in the layer .vpfPath, a ';' separated list of paths to VPF data
 * VMAPData.vpfPath=e:/VMAPLV0
 * # the name of the library bean, used by the VPFLayers to identify
 * # this bean as the one they want to use.
 * VMAPData.name=VMAPLEVEL0
 * # Maximum number of tiles to cache.
 * VMAPData.cacheSize=25
 *  
 * </pre>
 * 
 * The VMAPData maker name, or whatever other name you decide to name
 * it, has to be added to the openmap.components property list so the
 * LibraryBean will be created and added to the MapHandler. Of course,
 * you could add the LibraryBean to the MapHandler programmatically if
 * you wanted to.
 */
public class LibraryBean implements PropertyConsumer, Serializable {

    /** used for explicitly naming a library bean (name). */
    public static final String nameProperty = "name";

    /**
     * property extension used to set the VPF root directory
     * (vpfPath).
     */
    public static final String pathProperty = "vpfPath";

    /** Maximum size of tile cache (cacheSize). */
    public static final String cacheSizeProperty = "cacheSize";

    /** the lst for the path */
    private transient LibrarySelectionTable lst = null;

    /** the name of the bean set in properties, or the marker name */
    String beanName;

    /** used by set/getPropertyPrefix */
    private String propertyPrefix = null;

    /** the paths used in constructing the lst */
    private String[] paths;

    /**
     * The VPFFeatureCache to use for cached features.
     */
    protected VPFFeatureCache featureCache;

    /**
     * Construct an empty bean.
     */
    public LibraryBean() {
        featureCache = new VPFFeatureCache();
    }

    public void setProperties(Properties setList) {
        setProperties(getPropertyPrefix(), setList);
    }

    public void setProperties(String prefix, Properties setList) {
        setPropertyPrefix(prefix);
        String realPrefix = PropUtils.getScopedPropertyPrefix(prefix);

        paths = PropUtils.initPathsFromProperties(setList, realPrefix
                + pathProperty, paths);

        String beanName = setList.getProperty(realPrefix + nameProperty);
        this.beanName = (beanName == null) ? prefix : beanName;

        if (Debug.debugging("vpf")) {
            Debug.output("LibraryBean.setProperties(): " + prefix + " "
                    + this.beanName + " initialized");
        }
        try {
            if (paths == null) {
                Debug.output("VPF LibraryBean: path not set - expected "
                        + realPrefix + pathProperty + " property");
            } else {
                lst = new LibrarySelectionTable(paths);
            }
        } catch (com.bbn.openmap.io.FormatException f) {
            Debug.output(f.getMessage());
        } catch (NullPointerException npe) {
            Debug.output("LibraryBean.setProperties:" + prefix
                    + ": path name not valid");
        }

        int cacheSize = PropUtils.intFromProperties(setList, realPrefix
                + cacheSizeProperty, featureCache.getCacheSize());
        featureCache.resetCache(cacheSize);
    }

    /**
     * Gets the name of the component - if the name was explicitly
     * set, then return that, otherwise return the property prefix.
     */
    public String getName() {
        return beanName;
    }

    /**
     * Not a good PropertyConsumer yet, doesn't return values.
     */
    public Properties getProperties(Properties getList) {
        if (getList == null) {
            getList = new Properties();
        }
        String prefix = PropUtils.getScopedPropertyPrefix(this);
        getList.put(prefix + nameProperty, beanName);
        getList.put(prefix + cacheSizeProperty,
                Integer.toString(featureCache.getCacheSize()));
        return getList;
    }

    /**
     */
    public Properties getPropertyInfo(Properties list) {
        if (list == null) {
            list = new Properties();
        }

        list.put(nameProperty, "Name of Library Bean.");
        list.put(pathProperty, "List of VPF directories.");
        list.put(pathProperty + ScopedEditorProperty,
                "com.bbn.openmap.util.propertyEditor.MultiDirectoryPropertyEditor");
        list.put(cacheSizeProperty,
                "Maximun number of tiles to cache (25 is default).");

        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
     */
    public String getPropertyPrefix() {
        return propertyPrefix;
    }

    /**
     * Returns the LST for the path of this object.
     * 
     * @return an LST, null if the object didn't construct properly
     */
    public LibrarySelectionTable getLibrarySelectionTable() {
        return lst;
    }

    public VPFCachedFeatureGraphicWarehouse getWarehouse() {
        if (Debug.debugging("vpf")) {
            Debug.output("LibraryBean.getWarehouse(): creating warehouse.");
        }

        return new VPFCachedFeatureGraphicWarehouse(featureCache);
    }
}