org.opengis.cite.iso19142.util

Class DataSampler

java.lang.Object

org.opengis.cite.iso19142.util.DataSampler

public class DataSampler
extends Object

Obtains samples of the feature data available from the WFS under test. Instances of all feature types advertised in the service description are requested; some types may have no data.

Constructor Summary

Constructors

Constructor and Description
DataSampler(Document wfsCapabilities) Constructs a new DataSampler for a particular WFS implementation.

Method Summary

Methods

Modifier and Type	Method and Description
void	acquireFeatureData() Attempts to acquire instances of all feature types supported by the WFS using all supported GetFeature message bindings (request encodings).
boolean	deleteData() Deletes all saved data files.
Element	getFeatureById(String id) Returns a feature instance from the sample data.
Map<QName,FeatureTypeInfo>	getFeatureTypeInfo() Returns a Map containing information about the feature types supported by the WFS.
List<String>	getSimplePropertyValues(QName featureType, QName propName, String featureId) Returns a list containing the values (in document order) of the specified feature property in the sample data set.
Set<String>	selectRandomFeatureIdentifiers(QName featureType, int numId) Returns a set of identifiers for available feature instances of a given type.
void	setMaxFeatures(int maxFeatures) Sets the maximum number of features to include in the response entity.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DataSampler

public DataSampler(Document wfsCapabilities)

Constructs a new DataSampler for a particular WFS implementation.

Parameters:

wfsCapabilities - A DOM Document representing the service metadata (/wfs:WFS_Capabilities).

Method Detail

setMaxFeatures

public void setMaxFeatures(int maxFeatures)

Sets the maximum number of features to include in the response entity.

Parameters:

maxFeatures - An integer value > 0 (the default value is 25).

selectRandomFeatureIdentifiers

public Set<String> selectRandomFeatureIdentifiers(QName featureType,
                                         int numId)

Returns a set of identifiers for available feature instances of a given type. The identifiers are randomly selected from the sample data.

Parameters:

featureType - A QName representing the qualified name of some feature type.

numId - The desired number of identifiers.

Returns:

A Set containing zero or more feature identifiers.

getSimplePropertyValues

public List<String> getSimplePropertyValues(QName featureType,
                                   QName propName,
                                   String featureId)

Returns a list containing the values (in document order) of the specified feature property in the sample data set. The property value is converted to a string as if the XPath string() function were applied.

Parameters:

featureType - A QName representing the qualified name of some feature type.

propName - The name of the property.

featureId - A feature identifer (gml:id); if null or empty the evaluation context includes all members of the collection.

Returns:

A List containing simple property values; the list is empty if no values are found.

deleteData

public boolean deleteData()

Deletes all saved data files.

Returns:

true if all data files were deleted; false otherwise (see warnings in log file for details).

acquireFeatureData

public void acquireFeatureData()

Attempts to acquire instances of all feature types supported by the WFS using all supported GetFeature message bindings (request encodings). The feature representations are saved in a temporary file. If no data exist for a given feature type, FeatureTypeInfo.isInstantiated() returns false.

getFeatureTypeInfo

public Map<QName,FeatureTypeInfo> getFeatureTypeInfo()

Returns a Map containing information about the feature types supported by the WFS.

Returns:

A Map where the keys are QName objects representing the names of feature types advertised in the capabilities document.

getFeatureById

public Element getFeatureById(String id)

Returns a feature instance from the sample data.

Parameters:

id - The feature identifier (@gml:id).

Returns:

An Element representing a feature instance, or null if no matching feature is found.