/* Copyright (c) 2008 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.gdata.data.geo.impl;
import com.google.gdata.util.common.xml.XmlWriter;
import com.google.gdata.data.ExtensionDescription;
import com.google.gdata.data.ExtensionPoint;
import com.google.gdata.data.ExtensionProfile;
import com.google.gdata.data.geo.Namespaces;
import com.google.gdata.data.geo.Point;
import java.io.IOException;
/**
* Extension for a GML gml:Point element.
*
*
*/
@ExtensionDescription.Default(
nsAlias=Namespaces.GML_ALIAS,
nsUri=Namespaces.GML,
localName=GmlPoint.NAME)
public class GmlPoint extends ExtensionPoint implements Point {
static final String NAME = "Point";
/**
* Constructs an empty gml:Point element.
*/
public GmlPoint() {}
/**
* Constructs a gml:Point element out of the given lat and lon values.
* This will construct a gml:pos element to hold the actual values. If the
* values are null then an empty gml:pos element will be created.
*/
public GmlPoint(Double lat, Double lon) {
this(new GmlPos(lat, lon));
}
/**
* Constructs a gml:Point element using the given Point coordinates for the
* nested gml:pos element. If the point is already a gml:pos, then it will
* be used directly as the extension, otherwise a gml:pos element will be
* created as a copy of the given point.
*/
public GmlPoint(Point point) {
if (point != null) {
if (!(point instanceof GmlPos)) {
point = new GmlPos(point);
}
setExtension(point);
}
}
/**
* Returns the suggested extension description with configurable
* repeatability.
*/
public static ExtensionDescription getDefaultDescription(boolean repeatable) {
ExtensionDescription desc = new ExtensionDescription();
desc.setExtensionClass(GmlPoint.class);
desc.setNamespace(Namespaces.GML_NAMESPACE);
desc.setLocalName(NAME);
desc.setRepeatable(repeatable);
return desc;
}
/**
* Returns the suggested extension description and is repeatable.
*/
public static ExtensionDescription getDefaultDescription() {
return getDefaultDescription(true);
}
/*
* Declare the extensions for gml point. This contains a single element with
* the coordinate which is the actual point. This is for extensibility I
* believe, but it ends up just being an extra level of wrapping.
*/
@Override
public void declareExtensions(ExtensionProfile extProfile) {
// Declare the gml:pos extension.
extProfile.declare(GmlPoint.class,
GmlPos.getDefaultDescription(false));
super.declareExtensions(extProfile);
}
/**
* @return the value of the gml:pos element within this Point.
*/
public Double getLatitude() {
GmlPos coord = getExtension(GmlPos.class);
return coord != null ? coord.getLatitude() : null;
}
/**
* @return the value of the gml:pos element's longitude within this Point.
*/
public Double getLongitude() {
GmlPos coord = getExtension(GmlPos.class);
return coord != null ? coord.getLongitude() : null;
}
/**
* Sets the latitude and longitude of the gml:pos element of this Point to the
* latitude and longitude coordinates specified.
*
* @param lat The latitude coordinate of this point.
* @param lon the longitude coordinate of this point.
*/
public void setGeoLocation(Double lat, Double lon) {
GmlPos point = getExtension(GmlPos.class);
if (point != null) {
if (lat == null && lon == null) {
removeExtension(point);
} else {
point.setGeoLocation(lat, lon);
}
} else if (lat != null || lon != null) {
point = new GmlPos();
setExtension(point);
point.setGeoLocation(lat, lon);
}
}
/**
* Generates the XML corresponding to this gml point.
*/
@Override
public void generate(XmlWriter w, ExtensionProfile extProfile)
throws IOException {
generateStartElement(w, Namespaces.GML_NAMESPACE, NAME, null, null);
// Generate the inner extensions (gml:pos).
generateExtensions(w, extProfile);
w.endElement(Namespaces.GML_NAMESPACE, NAME);
}
}