io.jenetics.jpx.TrackSegment Maven / Gradle / Ivy
/*
* Java GPX Library (jpx-1.0.0).
* Copyright (c) 2016-2016 Franz Wilhelmstötter
*
* 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.
*
* Author:
* Franz Wilhelmstötter ([email protected])
*/
package io.jenetics.jpx;
import static java.lang.String.format;
import static java.util.Objects.requireNonNull;
import static io.jenetics.jpx.Lists.immutable;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.function.Consumer;
import java.util.function.Function;
import java.util.stream.Stream;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamWriter;
/**
* A Track Segment holds a list of Track Points which are logically connected in
* order. To represent a single GPS track where GPS reception was lost, or the
* GPS receiver was turned off, start a new Track Segment for each continuous
* span of track data.
*
* @author Franz Wilhelmstötter
* @version 1.0
* @since 1.0
*/
public final class TrackSegment implements Iterable, Serializable {
private static final long serialVersionUID = 1L;
private final List _points;
/**
* Create a new track-segment with the given points.
*
* @param points the points of the track-segment
*/
private TrackSegment(final List points) {
_points = immutable(points);
}
/**
* Return the track-points of this segment.
*
* @return the track-points of this segment
*/
public List getPoints() {
return _points;
}
/**
* Return a stream of {@link WayPoint} objects this track-segments contains.
*
* @return a stream of {@link WayPoint} objects this track-segment contains
*/
public Stream points() {
return _points.stream();
}
/**
* Return {@code true} if {@code this} track-segment doesn't contain any
* track-point.
*
* @return {@code true} if {@code this} track-segment is empty, {@code false}
* otherwise
*/
public boolean isEmpty() {
return _points.isEmpty();
}
@Override
public Iterator iterator() {
return _points.iterator();
}
@Override
public int hashCode() {
return _points.hashCode();
}
@Override
public boolean equals(final Object obj) {
return obj instanceof TrackSegment &&
((TrackSegment)obj)._points.equals(_points);
}
@Override
public String toString() {
return format("TrackSegment[points=%s]", _points.size());
}
/**
* Builder class for creating immutable {@code TrackSegment} objects.
*
* Creating a {@code TrackSegment} object with 3 track-points:
*
{@code
* final TrackSegment segment = TrackSegment.builder()
* .addPoint(p -> p.lat(48.2081743).lon(16.3738189).ele(160))
* .addPoint(p -> p.lat(48.2081743).lon(16.3738189).ele(161))
* .addPoint(p -> p.lat(48.2081743).lon(16.3738189).ele(162))))
* .build();
* }
*/
public static final class Builder {
private List _points;
private Builder() {
}
/**
* Set the way-points fo the track segment.
*
* @param points the track-segment points
* @return {@code this} {@code Builder} for method chaining
*/
public Builder points(final List points) {
_points = points;
return this;
}
/**
* Add a way-point to the track-segment.
*
* @param point the segment way-point
* @return {@code this} {@code Builder} for method chaining
* @throws NullPointerException if the given {@code href} is {@code null}
*/
public Builder addPoint(final WayPoint point) {
if (_points == null) {
_points = new ArrayList<>();
}
_points.add(requireNonNull(point));
return this;
}
/**
* Add a way-point to the track-segment, via the given way-point builder.
*
* Creating a {@code TrackSegment} object with 3 track-points:
*
{@code
* final TrackSegment segment = TrackSegment.builder()
* .addPoint(p -> p.lat(48.2081743).lon(16.3738189).ele(160))
* .addPoint(p -> p.lat(48.2081743).lon(16.3738189).ele(161))
* .addPoint(p -> p.lat(48.2081743).lon(16.3738189).ele(162))))
* .build();
* }
*
* @param point the segment way-point builder
* @return {@code this} {@code Builder} for method chaining
* @throws NullPointerException if the given {@code href} is {@code null}
*/
public Builder addPoint(final Consumer point) {
final WayPoint.Builder builder = WayPoint.builder();
point.accept(builder);
return addPoint(builder.build());
}
/**
* Create a new track-segment from the current builder state.
*
* @return a new track-segment from the current builder state
*/
public TrackSegment build() {
return new TrackSegment(_points);
}
}
/**
* Create a new track-segment builder.
*
* @return a new track-segment builder
*/
public static Builder builder() {
return new Builder();
}
/* *************************************************************************
* Static object creation methods
* ************************************************************************/
/**
* Create a new track-segment with the given points.
*
* @param points the points of the track-segment
* @return a new track-segment with the given points
* @throws NullPointerException if the given {@code points} sequence is
* {@code null}
*/
public static TrackSegment of(final List points) {
return new TrackSegment(points);
}
/* *************************************************************************
* XML stream object serialization
* ************************************************************************/
/**
* Writes this {@code Link} object to the given XML stream {@code writer}.
*
* @param writer the XML data sink
* @throws XMLStreamException if an error occurs
*/
void write(final XMLStreamWriter writer) throws XMLStreamException {
final XMLWriter xml = new XMLWriter(writer);
xml.write("trkseg",
xml.elems(_points, (p, w) -> p.write("trkpt", w))
);
}
@SuppressWarnings("unchecked")
static XMLReader reader() {
final Function creator = a -> TrackSegment.of(
(List)a[0]
);
return XMLReader.of(creator, "trkseg",
XMLReader.ofList(WayPoint.reader("trkpt"))
);
}
}