/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 2002-2008, Open Source Geospatial Foundation (OSGeo)
*
* 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 org.geotools.swt.tool;
import java.lang.reflect.Constructor;
import java.util.Collection;
import java.util.List;
import java.util.WeakHashMap;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Cursor;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.geotools.data.simple.SimpleFeatureCollection;
import org.geotools.feature.FeatureIterator;
import org.geotools.geometry.DirectPosition2D;
import org.geotools.geometry.jts.ReferencedEnvelope;
import org.geotools.map.MapContext;
import org.geotools.map.MapLayer;
import org.geotools.swt.control.JTextReporter;
import org.geotools.swt.event.MapMouseEvent;
import org.geotools.swt.utils.CursorManager;
import org.geotools.swt.utils.Messages;
import org.geotools.swt.utils.Utils;
import org.opengis.feature.Feature;
import org.opengis.feature.Property;
import com.vividsolutions.jts.geom.Geometry;
/**
* A cursor tool to retrieve information about features that the user clicks
* on with the mouse.
*
* <p>It works with {@code InfoToolHelper} objects which do
* the work of querying feature data. The primary reason for this design
* is to shield this class from the grid coverage classes so that
* users who are working purely with vector data are not forced to have
* JAI in the classpath.
*
* @see InfoToolHelper
*
* @author Michael Bedward
* @since 2.6
*
*
* @source $URL: http://svn.osgeo.org/geotools/trunk/modules/unsupported/swt/src/main/java/org/geotools/swt/tool/InfoTool.java $
*/
public class InfoTool extends CursorTool {
/** The tool name */
public static final String TOOL_NAME = Messages.getString("tool_name_info");
/** Tool tip text */
public static final String TOOL_TIP = Messages.getString("tool_tip_info");
/**
* Default distance fraction used with line and point features.
* When the user clicks on the map, this tool searches for features within
* a rectangle of width w centred on the mouse location, where w is the
* average map side length multiplied by the value of this constant.
*/
public static final double DEFAULT_DISTANCE_FRACTION = 0.01d;
private Cursor cursor;
private JTextReporter reporter;
private WeakHashMap<MapLayer, InfoToolHelper<?>> helperTable;
/**
* Constructor
*/
public InfoTool() {
cursor = CursorManager.getInstance().getInfoCursor();
helperTable = new WeakHashMap<MapLayer, InfoToolHelper<?>>();
}
/**
* Respond to a mouse click by querying each of the {@code MapLayers}. The
* details of features lying within the threshold distance of the mouse
* position are reported on screen using a {@code JTextReporter} dialog.
* <p>
* <b>Implementation note:</b> An instance of {@code InfoToolHelper} is created
* and cached for each of the {@code MapLayers}. The helpers are created using
* reflection to avoid direct references to grid coverage classes here that would
* required JAI (Java Advanced Imaging) to be on the classpath even when only
* vector layers are being used.
*
* @param ev mouse event
*
* @see JTextReporter
* @see InfoToolHelper
*/
@Override
public void onMouseClicked( MapMouseEvent ev ) {
DirectPosition2D pos = ev.getMapPosition();
report(pos);
MapContext context = getMapPane().getMapContext();
for( MapLayer layer : context.getLayers() ) {
if (layer.isSelected()) {
InfoToolHelper<?> helper = null;
String layerName = layer.getTitle();
if (layerName == null || layerName.length() == 0) {
layerName = layer.getFeatureSource().getName().getLocalPart();
}
if (layerName == null || layerName.length() == 0) {
layerName = layer.getFeatureSource().getSchema().getName().getLocalPart();
}
helper = helperTable.get(layer);
if (helper == null) {
if (Utils.isGridLayer(layer)) {
try {
Class< ? > clazz = Class.forName("org.geotools.swt.tool.GridLayerHelper");
Constructor< ? > ctor = clazz.getConstructor(MapContext.class, MapLayer.class);
helper = (InfoToolHelper<?>) ctor.newInstance(context, layer);
helperTable.put(layer, helper);
} catch (Exception ex) {
throw new IllegalStateException("Failed to create InfoToolHelper for grid layer", ex);
}
} else {
try {
Class< ? > clazz = Class.forName("org.geotools.swt.tool.VectorLayerHelper");
Constructor< ? > ctor = clazz.getConstructor(MapContext.class, MapLayer.class);
helper = (InfoToolHelper<?>) ctor.newInstance(context, layer);
helperTable.put(layer, helper);
} catch (Exception ex) {
throw new IllegalStateException("Failed to create InfoToolHelper for vector layer", ex);
}
}
}
Object info = null;
if (helper instanceof VectorLayerHelper) {
ReferencedEnvelope mapEnv = getMapPane().getDisplayArea();
double searchWidth = DEFAULT_DISTANCE_FRACTION * (mapEnv.getWidth() + mapEnv.getHeight()) / 2;
try {
info = helper.getInfo(pos, Double.valueOf(searchWidth));
} catch (Exception ex) {
throw new IllegalStateException(ex);
}
if (info != null) {
FeatureIterator< ? extends Feature> iter = null;
SimpleFeatureCollection selectedFeatures = (SimpleFeatureCollection) info;
try {
iter = selectedFeatures.features();
while( iter.hasNext() ) {
report(layerName, iter.next());
}
} catch (Exception ex) {
throw new IllegalStateException(ex);
} finally {
if (iter != null) {
iter.close();
}
}
}
} else {
try {
info = helper.getInfo(pos);
} catch (Exception ex) {
throw new IllegalStateException(ex);
}
if (info != null) {
@SuppressWarnings("unchecked")
List<Number> bandValues = (List<Number>) info;
if (!bandValues.isEmpty()) {
report(layerName, bandValues);
}
}
}
}
}
}
/**
* Write the mouse click position to a {@code JTextReporter}
*
* @param pos mouse click position (world coords)
*/
private void report( DirectPosition2D pos ) {
createReporter();
reporter.append(String.format("Pos \nx=%.4f \ny=%.4f\n\n", pos.x, pos.y));
}
/**
* Write the feature attribute names and values to a
* {@code JTextReporter}
*
* @param layerName name of the map layer that contains this feature
* @param feature the feature to report on
*/
private void report( String layerName, Feature feature ) {
createReporter();
Collection<Property> props = feature.getProperties();
String valueStr = null;
StringBuilder sb = new StringBuilder();
sb.append(layerName);
sb.append("\n");
for( Property prop : props ) {
String name = prop.getName().getLocalPart();
Object value = prop.getValue();
if (value instanceof Geometry) {
name = " Geometry";
valueStr = value.getClass().getSimpleName();
} else {
valueStr = value.toString();
}
sb.append(name);
sb.append(":");
sb.append(valueStr);
sb.append("\n\n");
}
reporter.append(sb.toString());
}
/**
* Write an array of grid coverage band values to a
* {@code JTextReporter}
*
* @param layerName name of the map layer that contains the grid coverage
* @param bandValues array of values
*/
private void report( String layerName, List<Number> bandValues ) {
createReporter();
StringBuilder sb = new StringBuilder();
sb.append("\n");
sb.append(layerName);
sb.append("\n");
int k = 1;
for( Number value : bandValues ) {
sb.append(String.format(" Band %d: %s\n", k++, value.toString()));
}
sb.append("\n\n");
reporter.append(sb.toString());
}
/**
* Create and show a {@code JTextReporter} if one is not already active
* for this tool
*/
private void createReporter() {
if (reporter == null || reporter.getShell() == null || reporter.getShell().isDisposed()) {
Shell shell = new Shell(Display.getCurrent(), SWT.TITLE | SWT.CLOSE | SWT.BORDER | SWT.MODELESS);
shell.setLayout(new GridLayout(1, false));
reporter = new JTextReporter(shell, "Map info");
reporter.open();
}
}
@Override
public Cursor getCursor() {
return cursor;
}
/**
* {@inheritDoc}
*
* @return Always returns false
*/
@Override
public boolean drawDragBox() {
return false;
}
}