Java tutorial
/* * GeoTools - The Open Source Java GIS Toolkit * http://geotools.org * * (C) 2004-2008, 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.data.wfs.internal.v1_x; import java.io.ByteArrayInputStream; import java.io.IOException; import java.io.InputStream; import java.io.StringWriter; import java.util.HashMap; import java.util.Map; import java.util.logging.Level; import javax.xml.namespace.QName; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.parsers.ParserConfigurationException; import javax.xml.transform.OutputKeys; import javax.xml.transform.Transformer; import javax.xml.transform.TransformerException; import javax.xml.transform.TransformerFactory; import javax.xml.transform.dom.DOMSource; import javax.xml.transform.stream.StreamResult; import net.opengis.wfs.FeatureTypeType; import org.apache.commons.io.IOUtils; import org.geotools.data.wfs.internal.WFSOperationType; import org.geotools.data.wfs.internal.WFSRequest; import org.geotools.xs.bindings.XSDoubleBinding; import org.geotools.xs.bindings.XSIntegerBinding; import org.geotools.xs.bindings.XSStringBinding; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.Node; import org.w3c.dom.NodeList; import org.xml.sax.SAXException; /** * This strategy addresses a bug in most MapServer implementations where a filter is required in * order for all the features to be returned. So if the Filter is Filter.NONE or Query.ALL then a * BBox Filter is constructed that is the entire layer. */ public class MapServerWFSStrategy extends StrictWFS_1_x_Strategy { private String mapServerVersion = ""; public MapServerWFSStrategy(Document capabilitiesDoc) { super(); getMapServerVersion(capabilitiesDoc); } @Override public FeatureTypeType translateTypeInfo(FeatureTypeType typeInfo) { if ("wfs".equals(typeInfo.getName().getPrefix()) || "http://www.opengis.net/wfs".equals(typeInfo.getName().getNamespaceURI())) { QName newName = new QName("http://mapserver.gis.umn.edu/mapserver", typeInfo.getName().getLocalPart(), "ms"); typeInfo.setName(newName); } return typeInfo; } @Override public Map<QName, Class<?>> getFieldTypeMappings() { Map<QName, Class<?>> mappings = new HashMap<QName, Class<?>>(); mappings.put(new QName("http://www.w3.org/2001/XMLSchema", "Character"), XSStringBinding.class); mappings.put(new QName("http://www.w3.org/2001/XMLSchema", "Integer"), XSIntegerBinding.class); mappings.put(new QName("http://www.w3.org/2001/XMLSchema", "Real"), XSDoubleBinding.class); return mappings; } @Override public InputStream getPostContents(WFSRequest request) throws IOException { InputStream in = super.getPostContents(request); if (request.getOperation().compareTo(WFSOperationType.GET_FEATURE) == 0 && getVersion().compareTo("1.0.0") == 0 && mapServerVersion != null) { try { // Pre-5.6.7 versions of MapServer do not support the following gml:Box coordinate format: // <gml:coord><gml:X>-59.0</gml:X><gml:Y>-35.0</gml:Y></gml:coord><gml:coord>< gml:X>-58.0</gml:X><gml:Y>-34.0</gml:Y></gml:coord> // Rewrite the coordinates in the following format: // <gml:coordinates cs="," decimal="." ts=" ">-59,-35 -58,-34</gml:coordinates> String[] tokens = mapServerVersion.split("\\."); if (tokens.length == 3 && versionCompare(mapServerVersion, "5.6.7") < 0) { StringWriter writer = new StringWriter(); IOUtils.copy(in, writer, "UTF-8"); String pc = writer.toString(); boolean reformatted = false; if (pc.contains("gml:Box") && pc.contains("gml:coord") && pc.contains("gml:X") && pc.contains("gml:Y")) { DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance(); factory.setNamespaceAware(true); DocumentBuilder builder = factory.newDocumentBuilder(); Document doc = builder.parse(new ByteArrayInputStream(pc.getBytes())); NodeList boxes = doc.getElementsByTagName("gml:Box"); for (int b = 0; b < boxes.getLength(); b++) { Element box = (Element) boxes.item(b); NodeList coords = box.getElementsByTagName("gml:coord"); if (coords != null && coords.getLength() == 2) { Element coord1 = (Element) coords.item(0); Element coord2 = (Element) coords.item(1); if (coord1 != null && coord2 != null) { Element coordX1 = (Element) (coord1.getElementsByTagName("gml:X").item(0)); Element coordY1 = (Element) (coord1.getElementsByTagName("gml:Y").item(0)); Element coordX2 = (Element) (coord2.getElementsByTagName("gml:X").item(0)); Element coordY2 = (Element) (coord2.getElementsByTagName("gml:Y").item(0)); if (coordX1 != null && coordY1 != null && coordX2 != null && coordY2 != null) { reformatted = true; String x1 = coordX1.getTextContent(); String y1 = coordY1.getTextContent(); String x2 = coordX2.getTextContent(); String y2 = coordY2.getTextContent(); box.removeChild(coord1); box.removeChild(coord2); Element coordinates = doc.createElement("gml:coordinates"); coordinates.setAttribute("cs", ","); coordinates.setAttribute("decimal", "."); coordinates.setAttribute("ts", " "); coordinates.appendChild( doc.createTextNode(x1 + "," + y1 + " " + x2 + "," + y2)); box.appendChild(coordinates); } } } } if (reformatted) { DOMSource domSource = new DOMSource(doc); StringWriter domsw = new StringWriter(); StreamResult result = new StreamResult(domsw); TransformerFactory tf = TransformerFactory.newInstance(); Transformer transformer = tf.newTransformer(); transformer.setOutputProperty(OutputKeys.ENCODING, "UTF-8"); transformer.setOutputProperty(OutputKeys.INDENT, "yes"); transformer.transform(domSource, result); domsw.flush(); pc = domsw.toString(); } } in = new ByteArrayInputStream(pc.getBytes()); } } catch (SAXException | ParserConfigurationException | TransformerException | IOException ex) { LOGGER.log(Level.FINE, "Unexpected exception while rewriting 1.0.0 GETFEATURE request with BBOX filter", ex.getMessage()); } } return in; } // // Mapserver returns its version in the WFS 1.0.0 getcapabilities response // void getMapServerVersion(Document capabilitiesDoc) { if (getVersion().compareTo("1.0.0") == 0) { Element cap = capabilitiesDoc.getDocumentElement(); NodeList childNodes = cap.getChildNodes(); for (int i = 0; i < childNodes.getLength(); i++) { Node child = childNodes.item(i); if (child.getNodeType() == Element.COMMENT_NODE) { String nodeValue = child.getNodeValue(); if (nodeValue != null && nodeValue.contains("MapServer version")) { String[] tokens = nodeValue.split("\\s"); if (tokens.length >= 4) { mapServerVersion = tokens[3]; break; } } } } } } /** * Compares two version strings. * * Use this instead of String.compareTo() for a non-lexicographical * comparison that works for version strings. e.g. "1.10".compareTo("1.6"). * * @note It does not work if "1.10" is supposed to be equal to "1.10.0". * * @param str1 a string of ordinal numbers separated by decimal points. * @param str2 a string of ordinal numbers separated by decimal points. * @return The result is a negative integer if str1 is _numerically_ less than str2. * The result is a positive integer if str1 is _numerically_ greater than str2. * The result is zero if the strings are _numerically_ equal. */ // Code from Stack Overflow: // http://stackoverflow.com/questions/6701948/efficient-way-to-compare-version-strings-in-java // private Integer versionCompare(String str1, String str2) { String[] vals1 = str1.split("\\."); String[] vals2 = str2.split("\\."); int i = 0; // set index to first non-equal ordinal or length of shortest version string while (i < vals1.length && i < vals2.length && vals1[i].equals(vals2[i])) { i++; } // compare first non-equal ordinal number if (i < vals1.length && i < vals2.length) { int diff = Integer.valueOf(vals1[i]).compareTo(Integer.valueOf(vals2[i])); return Integer.signum(diff); } // the strings are equal or one string is a substring of the other // e.g. "1.2.3" = "1.2.3" or "1.2.3" < "1.2.3.4" else { return Integer.signum(vals1.length - vals2.length); } } }