Java tutorial
/* * uDig - User Friendly Desktop Internet GIS client * http://udig.refractions.net * (C) 2004, Refractions Research Inc. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; * version 2.1 of the License. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * */ package net.refractions.udig.transformtool; import java.lang.reflect.InvocationTargetException; import java.util.ArrayList; import java.util.Iterator; import java.util.List; import net.refractions.udig.project.IBlackboard; import net.refractions.udig.project.IMap; import net.refractions.udig.project.internal.impl.LayerImpl; import net.refractions.udig.project.ui.ApplicationGIS; import org.eclipse.core.runtime.IProgressMonitor; import org.eclipse.core.runtime.IStatus; import org.eclipse.core.runtime.Status; import org.eclipse.jface.dialogs.ErrorDialog; import org.eclipse.jface.operation.IRunnableWithProgress; import org.eclipse.swt.widgets.Display; import org.geotools.data.FeatureSource; import org.geotools.feature.Feature; import org.geotools.geometry.DirectPosition2D; import org.geotools.geometry.GeneralDirectPosition; import org.geotools.geometry.jts.JTS; import org.geotools.referencing.crs.DefaultEngineeringCRS; import org.geotools.referencing.datum.DefaultEllipsoid; import org.geotools.referencing.operation.builder.MappedPosition; import org.geotools.referencing.operation.transform.GeocentricTransform; import org.opengis.referencing.crs.CoordinateReferenceSystem; import org.opengis.spatialschema.geometry.DirectPosition; import com.vividsolutions.jts.geom.Coordinate; import com.vividsolutions.jts.geom.Envelope; public class VectorLayerReader implements IRunnableWithProgress { public static final String BLACKBOARD_PTS = "net.refractions.udig.transformtool.PTS"; /* public static final String BLACKBOARD_PTSRC = "net.refractions.udig.transformtool.PTSRC"; public static final String BLACKBOARD_PTDST = "net.refractions.udig.transformtool.PTDST"; public static final String BLACKBOARD_PTSRC3D = "net.refractions.udig.transformtool.PTSRC3D"; public static final String BLACKBOARD_PTDST3D = "net.refractions.udig.transformtool.PTDST3D"; */ public VectorLayerReader() { super(); } public void run(IProgressMonitor monitor) throws InvocationTargetException, InterruptedException { IMap map = ApplicationGIS.getActiveMap(); List<MappedPosition> pts = new ArrayList(); if (map == null) { return; } IBlackboard blackboard = map.getBlackboard(); LayerImpl vectorLayer = (LayerImpl) blackboard.get(TransformTool.BLACKBOARD_VECTORLAYER); CoordinateReferenceSystem CRS = vectorLayer.getCRS(); DirectPosition2D[] ptSrc; DirectPosition2D[] ptDst; try { FeatureSource ft = (FeatureSource) vectorLayer.getResource(FeatureSource.class, null); //System.out.print("............"+vectorLayer.getCRS()); int i = 0; int size = ft.getFeatures().size(); monitor.beginTask("Reading...", size); for (Iterator j = ft.getFeatures().iterator(); j.hasNext();) { Feature feature = (Feature) j.next(); // System.out.println(feature.getDefaultGeometry().getCoordinates()); Coordinate[] coords = feature.getDefaultGeometry().getCoordinates(); if (feature.getDefaultGeometry().getCoordinates().length > 2) { throw new InterruptedException("Layer reading error"); } CoordinateReferenceSystem crs = DefaultEngineeringCRS.CARTESIAN_2D; pts.add(new MappedPosition(new DirectPosition2D(crs, coords[0].x, coords[0].y), new DirectPosition2D(crs, coords[1].x, coords[1].y))); // ptSrc[i] = new DirectPosition2D(crs,coords[0].x, coords[0].y); // ptDst[i] = new DirectPosition2D(crs,coords[1].x, coords[1].y); i++; monitor.worked(1); monitor.subTask("Reading " + i + ". of " + size + " vectors."); if (monitor.isCanceled()) { throw new InterruptedException("The long running operation was cancelled"); } monitor.done(); } blackboard.put(this.BLACKBOARD_PTS, pts); } catch (Exception e) { final Display finalDisplay = Display.getDefault(); Display.getDefault().asyncExec(new Runnable() { public void run() { Status status = new Status(IStatus.ERROR, "My Plug-in ID", 0, "Vector layer has to contain just Line Strings formed by two points.", null); ErrorDialog.openError(finalDisplay.getActiveShell(), "Error", "Unable to read selected vector layer.", status); } }); monitor.done(); } } private DirectPosition[] directPositionToGeocentric(DirectPosition[] point) { Envelope[] ptsE = new Envelope[point.length]; DirectPosition[] DstPoint3D = new DirectPosition[point.length]; for (int i = 0; i < ptsE.length; i++) { // CoordinateReferenceSystem s= sourceLayer.getCRS().toWKT(); ptsE[i] = new Envelope(new Coordinate(point[i].getCoordinates()[0], point[i].getCoordinates()[1])); try { IMap map = ApplicationGIS.getActiveMap(); IBlackboard blackboard = map.getBlackboard(); LayerImpl vectorLayer = (LayerImpl) blackboard.get(TransformTool.BLACKBOARD_VECTORLAYER); CoordinateReferenceSystem CRS = vectorLayer.getCRS(); // convert tp Geegraphic ptsE[i] = JTS.toGeographic(ptsE[i], CRS); DefaultEllipsoid ellipsoid = DefaultEllipsoid.WGS84; GeocentricTransform geocentric = new GeocentricTransform(ellipsoid, false); double[] point3D = { ptsE[i].getMinX(), ptsE[i].getMinY(), 0 }; double[] Dst = { 0, 0, 0 }; geocentric.transform(point3D, 0, Dst, 0, 1); DstPoint3D[i] = new GeneralDirectPosition(Dst[0], Dst[1], Dst[2]); } catch (Exception e) { e.printStackTrace(); } } return DstPoint3D; } }