/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 2002-2008, 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.v1_1_0.parsers;
import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PushbackInputStream;
import java.util.logging.Logger;
import net.opengis.wfs.GetFeatureType;
import org.eclipse.emf.ecore.EObject;
import org.geotools.data.wfs.protocol.wfs.WFSOperationType;
import org.geotools.data.wfs.protocol.wfs.WFSResponse;
import org.geotools.data.wfs.protocol.wfs.WFSResponseParser;
import org.geotools.data.wfs.protocol.wfs.WFSResponseParserFactory;
import org.geotools.data.wfs.v1_1_0.WFS_1_1_0_DataStore;
import org.geotools.util.logging.Logging;
/**
* A base WFS response parser factory for GetFeature requests.
*
* @author Mauro Bartolomeoli (mauro.bartolomeoli@geosolutions.it)
* @version $Id$
* @since 10
*
*
*
* @source $URL$
* http://gtsvn.refractions.net/trunk/modules/plugin/wfs/src/main/java/org/geotools/data
* /wfs/v1_1_0/parsers/GmlAbstractGetFeatureResponseParserFactory.java $
*/
@SuppressWarnings("nls")
public abstract class GmlAbstractGetFeatureResponseParserFactory implements WFSResponseParserFactory {
private static final Logger LOGGER = Logging.getLogger("org.geotools.data.wfs");
/**
* @see WFSResponseParserFactory#isAvailable()
*/
public boolean isAvailable() {
return true;
}
/**
* Checks if this factory can create a parser for the potential responses of the given WFS
* request.
* <p>
* For instance, this factory can create a parser as long as the request is a
* {@link GetFeatureType GetFeature} request and the request output format matches {@code
* "text/xml; subtype=gml/3.1.1"}.
* </p>
*
* @see WFSResponseParserFactory#canProcess(WFSOperationType, String)
*/
public boolean canProcess(EObject request) {
if (!(request instanceof GetFeatureType)) {
return false;
}
String outputFormat = ((GetFeatureType) request).getOutputFormat();
boolean matches = isSupportedOutputFormat(outputFormat);
return matches;
}
protected abstract boolean isSupportedOutputFormat(String outputFormat);
/**
* Returns either a {@link FeatureCollectionParser} or an {@link ExceptionReportParser}
* depending on what the server returned.
* <p>
* Ideally, the decision should only be taken based on the WFS response's content-type HTTP
* header. Truth is, some WFS implementations does not set proper HTTP response headers so a bit
* of an heuristic may be needed in order to identify the actual response.
* </p>
*
* @see WFSResponseParserFactory#createParser(WFS_1_1_0_DataStore, WFSResponse)
* @see FeatureCollectionParser
* @see ExceptionReportParser
*/
public WFSResponseParser createParser(WFS_1_1_0_DataStore wfs, WFSResponse response)
throws IOException {
final WFSResponseParser parser;
final String contentType = response.getContentType();
if (isSupportedOutputFormat(contentType)) {
parser = new FeatureCollectionParser();
} else {
// We can't rely on the server returning the correct output format. Some, for example
// CubeWerx, upon a successful GetFeature request, set the response's content-type
// header to plain "text/xml" instead of "text/xml;subtype=gml/3.1.1". So we'll do a bit
// of heuristics to find out what it actually returned
final int buffSize = 256;
PushbackInputStream pushbackIn = new PushbackInputStream(response.getInputStream(),
buffSize);
byte[] buff = new byte[buffSize];
int readCount = 0;
int r;
while ((r = pushbackIn.read(buff, readCount, buffSize - readCount)) != -1) {
readCount += r;
if (readCount == buffSize) {
break;
}
}
BufferedReader reader = new BufferedReader(new InputStreamReader(
new ByteArrayInputStream(buff), response.getCharacterEncoding()));
StringBuilder sb = new StringBuilder();
String line;
while ((line = reader.readLine()) != null) {
sb.append(line).append('\n');
}
String head = sb.toString();
LOGGER.fine("response head: " + head);
pushbackIn.unread(buff, 0, readCount);
response.setInputStream(pushbackIn);
if (head.contains("FeatureCollection")) {
parser = new FeatureCollectionParser();
} else if (head.contains("ExceptionReport")) {
parser = new ExceptionReportParser();
} else {
throw new IllegalStateException("Unknown server response: " + head);
}
}
return parser;
}
}