Java tutorial
/** * Copyright (C) 2012-2015 52North Initiative for Geospatial Open Source * Software GmbH * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published * by the Free Software Foundation. * * If the program is linked with libraries which are licensed under one of * the following licenses, the combination of the program with the linked * library is not considered a "derivative work" of the program: * * - Apache License, version 2.0 * - Apache Software License, version 1.0 * - GNU Lesser General Public License, version 3 * - Mozilla Public License, versions 1.0, 1.1 and 2.0 * - Common Development and Distribution License (CDDL), version 1.0 * * Therefore the distribution of the program linked with libraries licensed * under the aforementioned licenses, is permitted by the copyright holders * if the distribution is compliant with both the GNU General Public * License version 2 and the aforementioned licenses. * * This program 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 General * Public License for more details. */ package org.n52.sos.decode.json; import static org.n52.sos.util.DateTimeHelper.parseIsoString2DateTime; import java.util.Collections; import java.util.List; import java.util.Map; import java.util.Set; import org.joda.time.DateTime; import org.n52.sos.coding.CodingRepository; import org.n52.sos.coding.json.JSONConstants; import org.n52.sos.decode.Decoder; import org.n52.sos.decode.DecoderKey; import org.n52.sos.decode.JsonDecoderKey; import org.n52.sos.exception.ows.concrete.DateTimeParseException; import org.n52.sos.exception.ows.concrete.NoDecoderForKeyException; import org.n52.sos.ogc.OGCConstants; import org.n52.sos.ogc.gml.CodeType; import org.n52.sos.ogc.gml.CodeWithAuthority; import org.n52.sos.ogc.gml.time.Time; import org.n52.sos.ogc.gml.time.Time.TimeIndeterminateValue; import org.n52.sos.ogc.gml.time.TimeInstant; import org.n52.sos.ogc.gml.time.TimePeriod; import org.n52.sos.ogc.ows.OwsExceptionReport; import org.n52.sos.ogc.sos.SosConstants.SosIndeterminateTime; import org.n52.sos.service.ServiceConstants.SupportedTypeKey; import com.fasterxml.jackson.databind.JsonNode; import com.fasterxml.jackson.databind.node.ArrayNode; import com.google.common.collect.Lists; /** * TODO JavaDoc * * @author Christian Autermann <c.autermann@52north.org> * * @since 4.0.0 */ public abstract class JSONDecoder<T> implements Decoder<T, JsonNode> { private final Set<DecoderKey> decoderKeys; public JSONDecoder(Class<T> type) { this(Collections.<DecoderKey>singleton(new JsonDecoderKey(type))); } public JSONDecoder(Set<DecoderKey> keys) { this.decoderKeys = keys; } private <T> Decoder<T, JsonNode> getDecoder(Class<T> type) throws NoDecoderForKeyException { JsonDecoderKey key = new JsonDecoderKey(type); Decoder<T, JsonNode> decoder = CodingRepository.getInstance().getDecoder(key); if (decoder == null) { throw new NoDecoderForKeyException(key); } return decoder; } protected <T> T decodeJsonToObject(JsonNode json, Class<T> type) throws OwsExceptionReport { if (json == null || json.isNull() || json.isMissingNode()) { return null; } return getDecoder(type).decode(json); } protected <T> List<T> decodeJsonToObjectList(JsonNode node, Class<T> type) throws OwsExceptionReport { Decoder<T, JsonNode> decoder = getDecoder(type); if (node.isArray()) { List<T> filters = Lists.newArrayListWithExpectedSize(node.size()); for (JsonNode n : node) { if (n.isObject()) { filters.add(decoder.decode(n)); } } return filters; } else if (node.isObject()) { return Collections.singletonList(decoder.decode(node)); } else { return Collections.emptyList(); } } @Override public Set<DecoderKey> getDecoderKeyTypes() { return Collections.unmodifiableSet(decoderKeys); } @Override public T decode(JsonNode objectToDecode) throws OwsExceptionReport { return decodeJSON(objectToDecode, true); } @Override public Map<SupportedTypeKey, Set<String>> getSupportedTypes() { return Collections.emptyMap(); } @Override public Set<String> getConformanceClasses() { return Collections.emptySet(); } protected TimeInstant parseTimeInstant(JsonNode node) throws DateTimeParseException { if (node.isTextual()) { TimeInstant timeInstant = new TimeInstant(); String time = node.textValue(); if (TimeIndeterminateValue.template.equals(TimeIndeterminateValue.getEnumForString(time))) { timeInstant.setIndeterminateValue(TimeIndeterminateValue.template); } else if (SosIndeterminateTime.getEnumForString(time) != null) { // first, latest timeInstant.setSosIndeterminateTime(SosIndeterminateTime.getEnumForString(time)); } else { DateTime dateTime = parseDateTime(time); timeInstant.setValue(dateTime); } return timeInstant; } else { return null; } } protected TimePeriod parseTimePeriod(JsonNode node) throws DateTimeParseException { if (node.isArray()) { ArrayNode array = (ArrayNode) node; String startTime = array.get(0).textValue(); String endTime = array.get(1).textValue(); DateTime start = parseDateTime(startTime); DateTime end = parseDateTime(endTime); return new TimePeriod(start, end); } else { return null; } } protected DateTime parseDateTime(String time) throws DateTimeParseException { return parseIsoString2DateTime(time); } protected Time parseTime(JsonNode node) throws DateTimeParseException { if (node.isArray()) { return parseTimePeriod(node); } else if (node.isTextual()) { return parseTimeInstant(node); } else { return null; } } protected CodeWithAuthority parseCodeWithAuthority(JsonNode node) { if (node.isObject()) { String value = node.path(JSONConstants.VALUE).textValue(); String codespace = node.path(JSONConstants.CODESPACE).textValue(); if (codespace == null || codespace.isEmpty()) { codespace = OGCConstants.UNKNOWN; } return new CodeWithAuthority(value, codespace); } else if (node.isTextual()) { return new CodeWithAuthority(node.textValue(), OGCConstants.UNKNOWN); } else { return null; } } protected CodeType parseCodeType(JsonNode node) { if (node.isObject()) { String value = node.path(JSONConstants.VALUE).textValue(); String codespace = node.path(JSONConstants.CODESPACE).textValue(); if (codespace == null || codespace.isEmpty()) { codespace = OGCConstants.UNKNOWN; } return new CodeType(value).setCodeSpace(codespace); } else if (node.isTextual()) { return new CodeType(node.textValue()).setCodeSpace(OGCConstants.UNKNOWN); } else { return null; } } public abstract T decodeJSON(JsonNode node, boolean validate) throws OwsExceptionReport; }