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/* * Copyright 2015 the original author or authors. * * 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 org.springframework.data.mongodb.core.geo; import java.io.IOException; import java.util.ArrayList; import java.util.Collections; import java.util.List; import org.springframework.data.geo.Point; import com.fasterxml.jackson.core.JsonParser; import com.fasterxml.jackson.core.JsonProcessingException; import com.fasterxml.jackson.databind.DeserializationContext; import com.fasterxml.jackson.databind.JsonDeserializer; import com.fasterxml.jackson.databind.JsonNode; import com.fasterxml.jackson.databind.JsonSerializer; import com.fasterxml.jackson.databind.Module; import com.fasterxml.jackson.databind.module.SimpleModule; import com.fasterxml.jackson.databind.node.ArrayNode; /** * A Jackson {@link Module} to register custom {@link JsonSerializer} and {@link JsonDeserializer}s for GeoJSON types. * * @author Christoph Strobl * @author Oliver Gierke * @since 1.7 */ public class GeoJsonModule extends SimpleModule { private static final long serialVersionUID = -8723016728655643720L; public GeoJsonModule() { addDeserializer(GeoJsonPoint.class, new GeoJsonPointDeserializer()); addDeserializer(GeoJsonMultiPoint.class, new GeoJsonMultiPointDeserializer()); addDeserializer(GeoJsonLineString.class, new GeoJsonLineStringDeserializer()); addDeserializer(GeoJsonMultiLineString.class, new GeoJsonMultiLineStringDeserializer()); addDeserializer(GeoJsonPolygon.class, new GeoJsonPolygonDeserializer()); addDeserializer(GeoJsonMultiPolygon.class, new GeoJsonMultiPolygonDeserializer()); } /** * @author Christoph Strobl * @since 1.7 */ private static abstract class GeoJsonDeserializer<T extends GeoJson<?>> extends JsonDeserializer<T> { /* * (non-Javadoc) * @see com.fasterxml.jackson.databind.JsonDeserializer#deserialize(com.fasterxml.jackson.core.JsonParser, com.fasterxml.jackson.databind.DeserializationContext) */ @Override public T deserialize(JsonParser jp, DeserializationContext ctxt) throws IOException, JsonProcessingException { JsonNode node = jp.readValueAsTree(); JsonNode coordinates = node.get("coordinates"); if (coordinates != null && coordinates.isArray()) { return doDeserialize((ArrayNode) coordinates); } return null; } /** * Perform the actual deserialization given the {@literal coordinates} as {@link ArrayNode}. * * @param coordinates * @return */ protected abstract T doDeserialize(ArrayNode coordinates); /** * Get the {@link GeoJsonPoint} representation of given {@link ArrayNode} assuming {@code node.[0]} represents * {@literal x - coordinate} and {@code node.[1]} is {@literal y}. * * @param node can be {@literal null}. * @return {@literal null} when given a {@code null} value. */ protected GeoJsonPoint toGeoJsonPoint(ArrayNode node) { if (node == null) { return null; } return new GeoJsonPoint(node.get(0).asDouble(), node.get(1).asDouble()); } /** * Get the {@link Point} representation of given {@link ArrayNode} assuming {@code node.[0]} represents * {@literal x - coordinate} and {@code node.[1]} is {@literal y}. * * @param node can be {@literal null}. * @return {@literal null} when given a {@code null} value. */ protected Point toPoint(ArrayNode node) { if (node == null) { return null; } return new Point(node.get(0).asDouble(), node.get(1).asDouble()); } /** * Get the points nested within given {@link ArrayNode}. * * @param node can be {@literal null}. * @return {@literal empty list} when given a {@code null} value. */ protected List<Point> toPoints(ArrayNode node) { if (node == null) { return Collections.emptyList(); } List<Point> points = new ArrayList<Point>(node.size()); for (JsonNode coordinatePair : node) { if (coordinatePair.isArray()) { points.add(toPoint((ArrayNode) coordinatePair)); } } return points; } protected GeoJsonLineString toLineString(ArrayNode node) { return new GeoJsonLineString(toPoints((ArrayNode) node)); } } /** * {@link JsonDeserializer} converting GeoJSON representation of {@literal Point}. * * <pre> * <code> * { "type": "Point", "coordinates": [10.0, 20.0] } * </code> * </pre> * * @author Christoph Strobl * @since 1.7 */ private static class GeoJsonPointDeserializer extends GeoJsonDeserializer<GeoJsonPoint> { /* * (non-Javadoc) * @see org.springframework.data.mongodb.core.geo.GeoJsonModule.GeoJsonDeserializer#doDeserialize(com.fasterxml.jackson.databind.node.ArrayNode) */ @Override protected GeoJsonPoint doDeserialize(ArrayNode coordinates) { return toGeoJsonPoint(coordinates); } } /** * {@link JsonDeserializer} converting GeoJSON representation of {@literal LineString}. * * <pre> * <code> * { * "type": "LineString", * "coordinates": [ * [10.0, 20.0], [30.0, 40.0], [50.0, 60.0] * ] * } * </code> * </pre> * * @author Christoph Strobl * @since 1.7 */ private static class GeoJsonLineStringDeserializer extends GeoJsonDeserializer<GeoJsonLineString> { /* * (non-Javadoc) * @see org.springframework.data.mongodb.core.geo.GeoJsonModule.GeoJsonDeserializer#doDeserialize(com.fasterxml.jackson.databind.node.ArrayNode) */ @Override protected GeoJsonLineString doDeserialize(ArrayNode coordinates) { return new GeoJsonLineString(toPoints(coordinates)); } } /** * {@link JsonDeserializer} converting GeoJSON representation of {@literal MultiPoint}. * * <pre> * <code> * { * "type": "MultiPoint", * "coordinates": [ * [10.0, 20.0], [30.0, 40.0], [50.0, 60.0] * ] * } * </code> * </pre> * * @author Christoph Strobl * @since 1.7 */ private static class GeoJsonMultiPointDeserializer extends GeoJsonDeserializer<GeoJsonMultiPoint> { /* * (non-Javadoc) * @see org.springframework.data.mongodb.core.geo.GeoJsonModule.GeoJsonDeserializer#doDeserialize(com.fasterxml.jackson.databind.node.ArrayNode) */ @Override protected GeoJsonMultiPoint doDeserialize(ArrayNode coordinates) { return new GeoJsonMultiPoint(toPoints(coordinates)); } } /** * {@link JsonDeserializer} converting GeoJSON representation of {@literal MultiLineString}. * * <pre> * <code> * { * "type": "MultiLineString", * "coordinates": [ * [ [10.0, 20.0], [30.0, 40.0] ], * [ [50.0, 60.0] , [70.0, 80.0] ] * ] * } * </code> * </pre> * * @author Christoph Strobl * @since 1.7 */ private static class GeoJsonMultiLineStringDeserializer extends GeoJsonDeserializer<GeoJsonMultiLineString> { /* * (non-Javadoc) * @see org.springframework.data.mongodb.core.geo.GeoJsonModule.GeoJsonDeserializer#doDeserialize(com.fasterxml.jackson.databind.node.ArrayNode) */ @Override protected GeoJsonMultiLineString doDeserialize(ArrayNode coordinates) { List<GeoJsonLineString> lines = new ArrayList<GeoJsonLineString>(coordinates.size()); for (JsonNode lineString : coordinates) { if (lineString.isArray()) { lines.add(toLineString((ArrayNode) lineString)); } } return new GeoJsonMultiLineString(lines); } } /** * {@link JsonDeserializer} converting GeoJSON representation of {@literal Polygon}. * * <pre> * <code> * { * "type": "Polygon", * "coordinates": [ * [ [100.0, 0.0], [101.0, 0.0], [101.0, 1.0], [100.0, 1.0], [100.0, 0.0] ] * ] * } * </code> * </pre> * * @author Christoph Strobl * @since 1.7 */ private static class GeoJsonPolygonDeserializer extends GeoJsonDeserializer<GeoJsonPolygon> { /* * (non-Javadoc) * @see org.springframework.data.mongodb.core.geo.GeoJsonModule.GeoJsonDeserializer#doDeserialize(com.fasterxml.jackson.databind.node.ArrayNode) */ @Override protected GeoJsonPolygon doDeserialize(ArrayNode coordinates) { for (JsonNode ring : coordinates) { // currently we do not support holes in polygons. return new GeoJsonPolygon(toPoints((ArrayNode) ring)); } return null; } } /** * {@link JsonDeserializer} converting GeoJSON representation of {@literal MultiPolygon}. * * <pre> * <code> * { * "type": "MultiPolygon", * "coordinates": [ * [[[102.0, 2.0], [103.0, 2.0], [103.0, 3.0], [102.0, 3.0], [102.0, 2.0]]], * [[[100.0, 0.0], [101.0, 0.0], [101.0, 1.0], [100.0, 1.0], [100.0, 0.0]], * [[100.2, 0.2], [100.8, 0.2], [100.8, 0.8], [100.2, 0.8], [100.2, 0.2]]] * ] * } * </code> * </pre> * * @author Christoph Strobl * @since 1.7 */ private static class GeoJsonMultiPolygonDeserializer extends GeoJsonDeserializer<GeoJsonMultiPolygon> { /* * (non-Javadoc) * @see org.springframework.data.mongodb.core.geo.GeoJsonModule.GeoJsonDeserializer#doDeserialize(com.fasterxml.jackson.databind.node.ArrayNode) */ @Override protected GeoJsonMultiPolygon doDeserialize(ArrayNode coordinates) { List<GeoJsonPolygon> polygones = new ArrayList<GeoJsonPolygon>(coordinates.size()); for (JsonNode polygon : coordinates) { for (JsonNode ring : (ArrayNode) polygon) { polygones.add(new GeoJsonPolygon(toPoints((ArrayNode) ring))); } } return new GeoJsonMultiPolygon(polygones); } } }