crfpclient.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/corba/com/bbn/openmap/layer/rpf/corba/CRFPClient.java,v $
// $RCSfile: CRFPClient.java,v $
// $Revision: 1.3.2.2 $
// $Date: 2005/08/09 21:17:59 $
// $Author: dietrick $
// 
// **********************************************************************

package com.bbn.openmap.layer.rpf.corba;

import java.awt.Point;
import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.Vector;

import com.bbn.openmap.Environment;
import com.bbn.openmap.layer.rpf.RpfCoverageBox;
import com.bbn.openmap.layer.rpf.RpfFrameProvider;
import com.bbn.openmap.layer.rpf.RpfIndexedImageData;
import com.bbn.openmap.layer.rpf.RpfViewAttributes;
import com.bbn.openmap.layer.rpf.corba.CRpfFrameProvider.CRFPCADRGProjection;
import com.bbn.openmap.layer.rpf.corba.CRpfFrameProvider.CRFPCoverageBox;
import com.bbn.openmap.layer.rpf.corba.CRpfFrameProvider.CRFPViewAttributes;
import com.bbn.openmap.layer.rpf.corba.CRpfFrameProvider.LLPoint;
import com.bbn.openmap.layer.rpf.corba.CRpfFrameProvider.RawImage;
import com.bbn.openmap.layer.rpf.corba.CRpfFrameProvider.Server;
import com.bbn.openmap.layer.rpf.corba.CRpfFrameProvider.ServerHelper;
import com.bbn.openmap.omGraphics.OMColor;
import com.bbn.openmap.proj.CADRG;
import com.bbn.openmap.util.Debug;
import com.bbn.openmap.util.PropUtils;
import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGImageDecoder;

/**
 * An implementation of the RpfFrameProvider interface that uses CORBA
 * to get the subframe data via a server. The image data is
 * transmitted in jpeg format. This class requires the sunw package
 * that handles jpeg encoding/decoding.
 * <P>
 * 
 * The client can connect to the server in two different ways. The
 * client can locate the server using an IOR file that the server has
 * written. This IOR file is read using an URL. The server can also be
 * located using the CORBA naming service. The name should be in a
 * three part fomat <ROOT name>/ <PART2>/ <PART3>. The root name has
 * to be known by the nameserver and the entire string has to be used
 * by the server on startup. If both the IOR and name string are set,
 * the IOR is the thing that gets used.
 */
public class CRFPClient implements RpfFrameProvider {

    /** The property specifying the IOR URL. */
    public static final String iorUrlProperty = "ior";
    /** The name of the server, using the name service. */
    public static final String nameProperty = "name";
    /** The property specifying the initial JPEG quality. */
    public static final String JPEGQualityProperty = "jpegQuality";
    /** The CRFPServer. */
    protected transient Server server = null;
    /** The string used for the CORBA naming service. */
    protected String naming = null;
    /** The URL used for the IOR, to connect to the server that way. */
    protected URL iorURL = null;
    private String clientID = Environment.generateUniqueString();
    /**
     * The compression quality of the images. Lower quality images are
     * smaller.
     */
    public float jpegQuality = .8f;

    /**
     * We'll set up the connection to the server when it's needed, but
     * not here.
     */
    public CRFPClient() {}

    /**
     * Set the JPEG quality parameter for subframe transfer.
     * 
     * @param jq number between 0 and 1, should be between .4 and .8.
     *        Anything else is a waste.
     */
    public void setJpegQuality(float jq) {
        jpegQuality = jq;
    }

    /**
     * Get the quality setting for JPEG subframe retrieval.
     * 
     * @return float reflecting JPEG quality.
     */
    public float getJpegQuality() {
        return jpegQuality;
    }

    /**
     * Set the name used for the CORBA naming service.
     */
    public void setNaming(String CORBAName) {
        naming = CORBAName;
    }

    /**
     * Get the name used for the CORBA naming service.
     */
    public String getNaming() {
        return naming;
    }

    /**
     * If you want to connect to the server using an ior, set the URL
     * where it is located.
     */
    public void setIorURL(URL iorurl) {
        iorURL = iorurl;
    }

    /**
     * Get the URL for the ior.
     */
    public URL getIorURL() {
        return iorURL;
    }

    /**
     * Get the clientID string that is used by the server to keep
     * track of clients. This string in internally generated.
     */
    public String getClientID() {
        return clientID;
    }

    /**
     * Set all the RPF properties from a properties object.
     */
    public void setProperties(String prefix, java.util.Properties properties) {

        prefix = PropUtils.getScopedPropertyPrefix(prefix);

        jpegQuality = PropUtils.floatFromProperties(properties, prefix
                + JPEGQualityProperty, .8f);

        String url = properties.getProperty(prefix + iorUrlProperty);
        if (url != null) {
            try {
                iorURL = PropUtils.getResourceOrFileOrURL(url);
            } catch (MalformedURLException e) {
                throw new IllegalArgumentException("\"" + url + "\""
                        + " is malformed.");
            }
        }

        naming = properties.getProperty(prefix + nameProperty);
    }

    /**
     * When the client is deleted, it should sign off from the server,
     * so that it can free up it's cache for it.
     */
    protected void finalize() {
        if (Debug.debugging("crfp")) {
            Debug.output("CRFPClient.finalize(): calling shutdown");
        }
        try {
            if (server != null) {
                server.signoff(clientID);
            }
            server = null;
        } catch (org.omg.CORBA.SystemException e) {
            Debug.error("CRFPClient.finalize(): " + e);
        } catch (Throwable t) {
            Debug.error("CRFPClient.finalize(): " + t);
        }
    }

    /**
     * Returns true because the view attributes should be set if they
     * change at the RpfCacheHandler/RpfCacheManager.
     */
    public boolean needViewAttributeUpdates() {
        return true;
    }

    /**
     * Set the RpfViewAttribute object parameters, which describes
     * alot about what you'll be asking for later.
     * 
     * @param rva the view attributes.
     */
    public void setViewAttributes(RpfViewAttributes rva) {
        Server serv = getServer();
        if (serv == null || rva == null) {
            return;
        }

        try {
            serv.setViewAttributes(new CRFPViewAttributes((short) rva.numberOfColors, (short) rva.opaqueness, rva.scaleImages, rva.imageScaleFactor, rva.chartSeries),
                    clientID);
            Debug.message("crfp", "CRFPClient: setting attributes.");
        } catch (org.omg.CORBA.SystemException e) {
            handleCORBAError(e);
        }
    }

    /**
     * Given a projection that describes a map or geographical area,
     * return RpfCoverageBoxes that let you know how to locate and ask
     * for RpfSubframes.
     * 
     * @param ullat NW latitude.
     * @param ullon NW longitude
     * @param lrlat SE latitude
     * @param lrlon SE longitude
     * @param p a CADRG projection
     */
    public Vector getCoverage(float ullat, float ullon, float lrlat,
                              float lrlon, CADRG p) {

        CRFPCoverageBox[] boxes;
        Server serv = getServer();

        if (serv == null)
            return new Vector();

        LLPoint llpoint = new LLPoint(p.getCenter().getLatitude(), p.getCenter()
                .getLongitude());

        CRFPCADRGProjection proj = new CRFPCADRGProjection(llpoint, (short) p.getHeight(), (short) p.getWidth(), p.getScale(), (short) p.getZone());

        Debug.message("crfp", "CRFPClient: getting coverage from server.");

        try {
            boxes = serv.getCoverage(ullat, ullon, lrlat, lrlon, proj, clientID);
            return translateCRFPCoverageBoxes(boxes);
        } catch (org.omg.CORBA.SystemException e) {
            handleCORBAError(e);
        }

        return new Vector();
    }

    /**
     * Given a projection that describes a map or geographical area,
     * return RpfCoverageBoxes that let you know what bounding boxes
     * of data are available.
     * 
     * @param ullat NW latitude.
     * @param ullon NW longitude
     * @param lrlat SE latitude
     * @param lrlon SE longitude
     * @param p a CADRG projection
     */
    public Vector getCatalogCoverage(float ullat, float ullon, float lrlat,
                                     float lrlon, CADRG p,
                                     String chartSeriesCode) {
        CRFPCoverageBox[] boxes;
        Server serv = getServer();

        if (serv == null)
            return new Vector();

        LLPoint llpoint = new LLPoint(p.getCenter().getLatitude(), p.getCenter()
                .getLongitude());

        CRFPCADRGProjection proj = new CRFPCADRGProjection(llpoint, (short) p.getHeight(), (short) p.getWidth(), p.getScale(), (short) p.getZone());

        Debug.message("crfp",
                "CRFPClient: getting catalog coverage from server.");
        try {
            boxes = serv.getCatalogCoverage(ullat,
                    ullon,
                    lrlat,
                    lrlon,
                    proj,
                    chartSeriesCode,
                    clientID);
            return translateCRFPCoverageBoxes(boxes);
        } catch (org.omg.CORBA.SystemException e) {
            handleCORBAError(e);
        }

        return new Vector();
    }

    /**
     * Given an area and a two-letter chart series code, find the
     * percentage of coverage on the map that that chart series can
     * offer. If you want specific coverage information, use the
     * getCatalogCoverage call.
     * 
     * @see #getCatalogCoverage(float ullat, float ullon, float lrlat,
     *      float lrlon, CADRG p, String chartSeriesCode)
     */
    public float getCalculatedCoverage(float ullat, float ullon, float lrlat,
                                       float lrlon, CADRG p, String chartSeries) {
        if (chartSeries.equalsIgnoreCase(RpfViewAttributes.ANY)) {
            return 0f;
        }

        Vector results = getCatalogCoverage(ullat,
                ullon,
                lrlat,