src.gov.nasa.worldwind.ogc.OGCCapabilities Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of worldwindx Show documentation
Show all versions of worldwindx Show documentation
World Wind is a collection of components that interactively display 3D geographic information within Java applications or applets.
/*
* Copyright (C) 2012 United States Government as represented by the Administrator of the
* National Aeronautics and Space Administration.
* All Rights Reserved.
*/
package gov.nasa.worldwind.ogc;
import gov.nasa.worldwind.util.*;
import gov.nasa.worldwind.util.xml.*;
import javax.xml.namespace.QName;
import javax.xml.stream.*;
import javax.xml.stream.events.*;
import java.util.Iterator;
/**
* Parses OGC Capabilities documents and holds the parsed information.
*
* @author tag
* @version $Id: OGCCapabilities.java 1171 2013-02-11 21:45:02Z dcollins $
*/
abstract public class OGCCapabilities extends AbstractXMLEventParser
{
/**
* Returns the default namespace URI. Must be overridden by subclasses to provide a specific URI. The default
* namespace is used to match XML elements found in the default namespace of the XML stream.
*
* @return the default namespace URI.
*/
abstract public String getDefaultNamespaceURI();
// Element names, constructed when the namespaceURI is known
protected QName SERVICE;
protected QName CAPABILITY;
protected QName VERSION;
protected QName UPDATE_SEQUENCE;
protected String version;
protected String updateSequence;
protected OGCServiceInformation serviceInformation;
protected OGCCapabilityInformation capabilityInformation;
protected XMLEventReader eventReader;
protected XMLEventParserContext parserContext;
/**
* Determines whether a specified element name is the root element name of the schema.
*
* @param name the name to test.
*
* @return true if the name is the schema's root element, otherwise false.
*/
abstract public boolean isRootElementName(QName name); // implement to test name of root element
/**
* Create a new capabilities parser.
*
* @param namespaceURI the default namespace URI.
* @param docSource the XML source. May be a filename, file, stream or other type allowed by {@link
* WWXML#openEventReader(Object)}.
*
* @throws IllegalArgumentException if the document source is null.
*/
public OGCCapabilities(String namespaceURI, Object docSource)
{
super(namespaceURI);
this.eventReader = this.createReader(docSource);
this.initialize();
}
private void initialize()
{
this.parserContext = this.createParserContext(this.eventReader);
SERVICE = new QName(this.getNamespaceURI(), "Service");
CAPABILITY = new QName(this.getNamespaceURI(), "Capability");
VERSION = new QName(this.getNamespaceURI(), "version");
UPDATE_SEQUENCE = new QName(this.getNamespaceURI(), "updateSequence");
this.getParserContext().registerParser(SERVICE, new OGCServiceInformation(this.getNamespaceURI()));
// Capability parser is registered by subclass.
}
protected XMLEventReader createReader(Object docSource)
{
return WWXML.openEventReader(docSource);
}
protected XMLEventParserContext createParserContext(XMLEventReader reader)
{
this.parserContext = new BasicXMLEventParserContext(reader);
this.parserContext.setDefaultNamespaceURI(this.getDefaultNamespaceURI());
return this.parserContext;
}
/** {@inheritDoc} */
public XMLEventParser allocate(XMLEventParserContext ctx, XMLEvent event)
{
if (ctx == null)
{
String message = Logging.getMessage("nullValue.ParserContextIsNull");
Logging.logger().severe(message);
throw new IllegalArgumentException(message);
}
XMLEventParser defaultParser = null;
if (ctx.isStartElement(event, SERVICE))
defaultParser = new OGCServiceInformation(this.getNamespaceURI());
return ctx.allocate(event, defaultParser);
}
/**
* Starts document parsing. This method initiates parsing of the XML document and returns when the full capabilities
* document has been parsed.
*
* @param args optional arguments to pass to parsers of sub-elements.
*
* @return this if parsing is successful, otherwise null.
*
* @throws XMLStreamException if an exception occurs while attempting to read the event stream.
*/
public OGCCapabilities parse(Object... args) throws XMLStreamException
{
XMLEventParserContext ctx = this.parserContext;
for (XMLEvent event = ctx.nextEvent(); ctx.hasNext(); event = ctx.nextEvent())
{
if (event == null)
continue;
if (event.isStartElement() && this.isRootElementName(event.asStartElement().getName()))
{
super.parse(ctx, event, args);
return this;
}
}
return null;
}
protected void doParseEventContent(XMLEventParserContext ctx, XMLEvent event, Object... args)
throws XMLStreamException
{
if (ctx.isStartElement(event, SERVICE))
{
XMLEventParser parser = this.allocate(ctx, event);
if (parser != null)
{
Object o = parser.parse(ctx, event, args);
if (o != null && o instanceof OGCServiceInformation)
this.setServiceInformation((OGCServiceInformation) o);
}
}
else if (ctx.isStartElement(event, CAPABILITY))
{
XMLEventParser parser = this.allocate(ctx, event);
if (parser != null)
{
Object o = parser.parse(ctx, event, args);
if (o != null && o instanceof OGCCapabilityInformation)
this.setCapabilityInformation((OGCCapabilityInformation) o);
}
}
}
@Override
protected void doParseEventAttributes(XMLEventParserContext ctx, XMLEvent event, Object... args)
{
Iterator iter = event.asStartElement().getAttributes();
if (iter == null)
return;
while (iter.hasNext())
{
Attribute attr = (Attribute) iter.next();
if (ctx.isSameAttributeName(attr.getName(), VERSION))
this.setVersion(attr.getValue());
else if (ctx.isSameAttributeName(attr.getName(), UPDATE_SEQUENCE))
this.setUpdateSequence(attr.getValue());
}
}
protected XMLEventParserContext getParserContext()
{
return this.parserContext;
}
/**
* Returns the document's service information.
*
* @return the document's service information.
*/
public OGCServiceInformation getServiceInformation()
{
return serviceInformation;
}
protected void setServiceInformation(OGCServiceInformation serviceInformation)
{
this.serviceInformation = serviceInformation;
}
protected void setCapabilityInformation(OGCCapabilityInformation capabilityInformation)
{
this.capabilityInformation = capabilityInformation;
}
/**
* Returns the document's capability information.
*
* @return the document's capability information.
*/
public OGCCapabilityInformation getCapabilityInformation()
{
return capabilityInformation;
}
/**
* Returns the document's version number.
*
* @return the document's version number.
*/
public String getVersion()
{
return version;
}
protected void setVersion(String version)
{
this.version = version;
}
/**
* Returns the document's update sequence.
*
* @return the document's update sequence.
*/
public String getUpdateSequence()
{
return updateSequence;
}
protected void setUpdateSequence(String updateSequence)
{
this.updateSequence = updateSequence;
}
@Override
public String toString()
{
StringBuilder sb = new StringBuilder();
sb.append("Version: ").
append(this.getVersion() != null ? this.getVersion() : "none").append("\n");
sb.append("UpdateSequence: ").
append(this.getUpdateSequence() != null ? this.getUpdateSequence() : "none");
sb.append("\n");
sb.append(this.getServiceInformation() != null ? this.getServiceInformation() : "Service Information: none");
sb.append("\n");
sb.append(this.getCapabilityInformation() != null
? this.getCapabilityInformation() : "Capability Information: none");
sb.append("\n");
return sb.toString();
}
}