describeresponse.java

电子地图服务器,搭建自己的地图服务

/* Copyright (c) 2001 - 2007 TOPP - www.openplans.org. All rights reserved.
 * This code is licensed under the GPL 2.0 license, availible at the root
 * application directory.
 */
package org.vfny.geoserver.wcs.responses;

import org.geotools.factory.Hints;
import org.geotools.geometry.GeneralEnvelope;
import org.geotools.referencing.ReferencingFactoryFinder;
import org.opengis.coverage.grid.GridGeometry;
import org.opengis.referencing.crs.CRSAuthorityFactory;
import org.opengis.referencing.crs.CRSFactory;
import org.opengis.referencing.datum.DatumFactory;
import org.opengis.referencing.operation.CoordinateOperationFactory;
import org.opengis.referencing.operation.MathTransformFactory;
import org.opengis.util.InternationalString;
import org.vfny.geoserver.Request;
import org.vfny.geoserver.Response;
import org.vfny.geoserver.global.CoverageDimension;
import org.vfny.geoserver.global.CoverageInfo;
import org.vfny.geoserver.global.GeoServer;
import org.vfny.geoserver.global.Service;
import org.vfny.geoserver.global.WCS;
import org.vfny.geoserver.wcs.WcsException;
import org.vfny.geoserver.wcs.requests.DescribeRequest;
import org.vfny.geoserver.wcs.requests.WCSRequest;
import java.io.IOException;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.TreeSet;
import java.util.logging.Logger;


/**
 * DOCUMENT ME!
 *
 * @author $Author: Alessio Fabiani ([e-mail]) $ (last
 *         modification)
 * @author $Author: Simone Giannecchini ([e-mail]) $ (last
 *         modification)
 */
public class DescribeResponse implements Response {
    private static final Logger LOGGER = org.geotools.util.logging.Logging.getLogger("org.vfny.geoserver.responses");
    private static final String CURR_VER = "\"1.0.0\"";
    private static final String WCS_URL = "http://www.opengis.net/wcs";
    private static final String WCS_NAMESPACE = new StringBuffer("\n  xmlns=\"").append(WCS_URL)
                                                                                .append("\"")
                                                                                .toString();
    private static final String XLINK_URL = "\"http://www.w3.org/1999/xlink\"";
    private static final String XLINK_NAMESPACE = new StringBuffer("\n  xmlns:xlink=").append(XLINK_URL)
                                                                                      .toString();
    private static final String OGC_URL = "\"http://www.opengis.net/ogc\"";
    private static final String OGC_NAMESPACE = new StringBuffer("\n  xmlns:ogc=").append(OGC_URL)
                                                                                  .toString();
    private static final String GML_URL = "\"http://www.opengis.net/gml\"";
    private static final String GML_NAMESPACE = new StringBuffer("\n  xmlns:gml=").append(GML_URL)
                                                                                  .toString();
    private static final String SCHEMA_URI = "\"http://www.w3.org/2001/XMLSchema-instance\"";
    private static final String XSI_NAMESPACE = new StringBuffer("\n  xmlns:xsi=").append(SCHEMA_URI)
                                                                                  .toString();

    /** Fixed return footer information */
    private static final String FOOTER = "\n</CoverageDescription>";

    /**
     *
     * @uml.property name="request"
     * @uml.associationEnd multiplicity="(0 1)"
     */
    private DescribeRequest request;

    /** Main XML class for interpretation and response. */
    private String xmlResponse = new String();

    /**
     * The default datum factory.
     *
     * @uml.property name="datumFactory"
     * @uml.associationEnd multiplicity="(1 1)"
     */
    protected final DatumFactory datumFactory = ReferencingFactoryFinder.getDatumFactory(null);

    /**
     * Returns any extra headers that this service might want to set in the HTTP response object.
     * @see org.vfny.geoserver.Response#getResponseHeaders()
     */
    public HashMap getResponseHeaders() {
        return null;
    }

    /**
     * The default coordinate reference system factory.
     */

    // protected final static CRSFactory crsFactory =
    // FactoryFinder.getCRSFactory(new
    // Hints(Hints.CRS_AUTHORITY_FACTORY,EPSGCRSAuthorityFactory.class));
    protected final static CRSFactory crsFactory = ReferencingFactoryFinder.getCRSFactory(new Hints(
                Hints.CRS_AUTHORITY_FACTORY, CRSAuthorityFactory.class));

    /**
     * The default math transform factory.
     *
     * @uml.property name="mtFactory"
     * @uml.associationEnd multiplicity="(1 1)"
     */
    protected final MathTransformFactory mtFactory = ReferencingFactoryFinder
        .getMathTransformFactory(null);

    /**
     * The default transformations factory.
     */
    protected final static CoordinateOperationFactory opFactory = ReferencingFactoryFinder
        .getCoordinateOperationFactory(new Hints(Hints.LENIENT_DATUM_SHIFT, Boolean.TRUE));

    public void execute(Request req) throws WcsException {
        WCSRequest request = (WCSRequest) req;

        if (!(request instanceof DescribeRequest)) {
            throw new WcsException(new StringBuffer(
                    "illegal request type, expected DescribeRequest, got ").append(request)
                                                                                                           .toString());
        }

        DescribeRequest wcsRequest = (DescribeRequest) request;
        this.request = wcsRequest;
        LOGGER.finer("processing describe request" + wcsRequest);

        String outputFormat = wcsRequest.getOutputFormat();

        if (!outputFormat.equalsIgnoreCase("XMLSCHEMA")) {
            throw new WcsException(new StringBuffer("output format: ").append(outputFormat)
                                                                      .append(" not ")
                                                                      .append("supported by geoserver")
                                                                      .toString());
        }

        // generates response, using general function
        xmlResponse = generateCoverages(wcsRequest);

        if (!request.getWCS().getGeoServer().isVerbose()) {
            xmlResponse = xmlResponse.replaceAll(">\n[ \\t\\n]*", ">");
            xmlResponse = xmlResponse.replaceAll("\n[ \\t\\n]*", " ");
        }
    }

    public String getContentType(GeoServer gs) {
        return gs.getMimeType();
    }

    public String getContentEncoding() {
        return null;
    }

    public String getContentDisposition() {
        return null;
    }

    public void writeTo(OutputStream out) throws WcsException {
        try {
            byte[] content = xmlResponse.getBytes();
            out.write(content);
        } catch (IOException ex) {
            throw new WcsException(ex, "", getClass().getName());
        }
    }

    private final String generateCoverages(DescribeRequest wcsRequest)
        throws WcsException {
        List requestedTypes = wcsRequest.getCoverages();

        // Initialize return information and intermediate return objects
        StringBuffer tempResponse = new StringBuffer();

        // ComplexType table = new ComplexType();
        if (requestedTypes.size() == 0) {
            // if there are no specific requested types then get all.
            requestedTypes = new ArrayList(wcsRequest.getWCS().getData().getCoverageInfos().keySet());
        }

        tempResponse.append("<?xml version=\"1.0\" encoding=\"")
                    .append(wcsRequest.getGeoServer().getCharSet().displayName()).append("\"?>")
                    .append("\n<CoverageDescription version=").append(CURR_VER).append(" ")
                    .toString();

        tempResponse.append(WCS_NAMESPACE);
        tempResponse.append(XLINK_NAMESPACE);
        tempResponse.append(OGC_NAMESPACE);
        tempResponse.append(GML_NAMESPACE);
        tempResponse.append(XSI_NAMESPACE);
        /*tempResponse.append(" xsi:schemaLocation=\"").append(WCS_URL).append(
                        " ").append(request.getSchemaBaseUrl()).append(
                        "wcs/1.0.0/describeCoverage.xsd\">\n\n");*/
        tempResponse.append(" xsi:schemaLocation=\"").append(WCS_URL).append(" ")
                    .append("http://schemas.opengis.net/wcs/1.0.0/")
                    .append("describeCoverage.xsd\">\n\n");

        tempResponse.append(generateSpecifiedCoverages(requestedTypes, wcsRequest.getWCS()));

        tempResponse.append(FOOTER);

        return tempResponse.toString();
    }

    private String generateSpecifiedCoverages(List requestedTypes, WCS gs)
        throws WcsException {
        String tempResponse = new String();
        String curCoverageName = new String();

        final int length = requestedTypes.size();
        CoverageInfo meta;

        for (int i = 0; i < length; i++) {
            curCoverageName = requestedTypes.get(i).toString();

            meta = gs.getData().getCoverageInfo(curCoverageName);

            if (meta == null) {
                throw new WcsException(new StringBuffer("Coverage ").append(curCoverageName)
                                                                    .append(" does ")
                                                                    .append("not exist on this server")
                                                                    .toString());
            }

            tempResponse = tempResponse + printElement(meta);
        }

        tempResponse = tempResponse + "\n\n";

        return tempResponse;
    }

    private static String printElement(CoverageInfo cv) {
        StringBuffer tempResponse = new StringBuffer();

        tempResponse.append("\n <CoverageOffering>");

        if (cv.getMetadataLink() != null) {
            tempResponse.append("\n  <metadataLink about=\"").append(cv.getMetadataLink().getAbout())
                        .append("\" metadataType=\"").append(cv.getMetadataLink().getMetadataType())
                        .append("\"/>");
        }

        String tmp = cv.getDescription();

        if ((tmp != null) && (tmp != "")) {
            tempResponse.append("\n  <description>").append(tmp).append("</description>");
        }

        tmp = cv.getName();

        if ((tmp != null) && (tmp != "")) {
            tempResponse.append("\n  <name>").append(tmp).append("</name>");
        }

        tmp = cv.getLabel();

        if ((tmp != null) && (tmp != "")) {
            tempResponse.append("\n  <label>").append(tmp).append("</label>");
        }

        final GeneralEnvelope envelope = cv.getWGS84LonLatEnvelope();

        tempResponse.append("\n  <lonLatEnvelope" + " srsName=\"WGS84(DD)\"") /*urn:ogc:def:crs:OGC:1.3:CRS84*/
                    .append(">");
        tempResponse.append("\n   <gml:pos>").append(envelope.getLowerCorner().getOrdinate(0))