Application: gvSIG desktop

import java.io.FileInputStream;

import java.nio.ByteBuffer;

import java.nio.channels.FileChannel;

import java.util.Iterator;

    public File getLegendGraphic_old(WMSStatus status, String layerName, ICancellable cancel) throws ServerErrorException, WMSException

    public File getLegendGraphic(WMSStatus status, String layerName, ICancellable cancel) 

    	throws ServerErrorException, WMSException {

    	URL request = null;

		try {

			request = new URL(buildGetLegendGraphicRequest(status, layerName));

			System.out.println(request);

            File f = Utilities.downloadFile(request, "wmsGetLegendGraphic", cancel);

	    	if (f== null)

	    		return null;

            if (Utilities.isTextFile(f)) {

	    		FileInputStream fis = new FileInputStream(f);

	    		FileChannel fc = fis.getChannel();

	    		byte[] data = new byte[(int)fc.size()];

	    		ByteBuffer bb = ByteBuffer.wrap(data);

	    		fc.read(bb);

	    		WMSException wmsEx = null;

            	String exceptionMessage = parseException(data);

                if (exceptionMessage == null) {

                 	String error = new String(data);

                	int pos = error.indexOf("<?xml");

                	if (pos!= -1) {

                		String xml = error.substring(pos,error.length());

                		exceptionMessage = parseException(xml.getBytes());

                	}

                    if (exceptionMessage == null)

                    	exceptionMessage = new String(data);

                }

             	wmsEx = new WMSException(exceptionMessage);

            	wmsEx.setWMSMessage(new String(data));

            	Utilities.removeURL(request);

                throw wmsEx;

            }

			return f;

		} catch(IOException e) {

			e.printStackTrace();

            throw new ServerErrorException();

		}

    }

    /**

     * @return string that represents the url for getting the wms legend

     * If the layer has the object layer-->style-->legendurl that url will be returned 

     * otherwise builds the getLegendGraphic according to the OGC WMS Specifications

     * 

     */

    private String buildGetLegendGraphicRequest(WMSStatus status, String layerName) {

    	//TODO: deal with more than one layer    	

    	WMSLayer lyr = (WMSLayer) this.layers.get(layerName);

    	WMSStyle sty =null;

    	if (lyr != null){

    		Iterator it = lyr.getStyles().iterator();

    		while (it.hasNext()){

    			sty = (WMSStyle) it.next();

    			if (sty.getName().equals(status.getStyles().get(0).toString())){    				

    				return sty.getLegendURLOnlineResourceHRef();

    			}

    		}

    	}

    	//TODO: pass by parameter the legend output format?

		StringBuffer req = new StringBuffer();

		String symbol = null;

		String onlineResource = null;

		if (status.getOnlineResource() == null)

			onlineResource = getHost();

		else

			onlineResource = status.getOnlineResource();

		symbol = getSymbol(onlineResource);

		req.append(onlineResource + symbol + "REQUEST=GetLegendGraphic&SERVICE=WMS&VERSION=").append(getVersion());

        req.append("&LAYER=" + layerName).append("&TRANSPARENT=TRUE").append("&FORMAT=image/png");

        String aux = req.toString().replaceAll(" ", "%20");

        System.out.println("GetLegendGraphic url:" + aux);

		return aux;

    }