org.geotools.data.vpf
Class VPFFeatureType

java.lang.Object
  org.geotools.data.vpf.VPFFeatureType

All Implemented Interfaces:

FeatureType

public class VPFFeatureType

extends java.lang.Object

implements FeatureType

A VPF feature type. Note that feature classes may contain one or more feature types. However, all of the feature types of a feature class share the same schema. A feature type will therefore delegate its schema related operations to its feature class.

Author:

Jeff Yutzler

Constructor Summary

VPFFeatureType(VPFFeatureClass cFeatureClass)
A constructor for feature types with no information in a char.vdt file.

VPFFeatureType(VPFFeatureClass cFeatureClass, Feature cFeature)
Constructor

Method Summary

Feature	create(java.lang.Object[] attributes) Scheduled for removal in Geotools 2.2, please use FeatureFactory.
Feature	create(java.lang.Object[] attributes, java.lang.String featureID) Scheduled for removal in Geotools 2.2, please use FeatureFactory.
Feature	duplicate(Feature feature) Create a duplicate of the provided feature, must delegate to an appropriate FeatureFactory create method.
boolean	equals(java.lang.Object obj) FeatureType check based on namespace, typeName, attributes and ancestors.
int	find(AttributeType type) Find the position of a given AttributeType.
int	find(java.lang.String attName) Find the position of an AttributeType which matches the given String.
FeatureType[]	getAncestors() Obtain an array of this FeatureType's direct ancestors.
int	getAttributeCount() The number of attribues defined by this schema.
AttributeType	getAttributeType(int position) Gets the schema attributeType at the specified index.
AttributeType	getAttributeType(java.lang.String xPath) Gets the attributeType at this xPath, if the specified attributeType does not exist then null is returned.
AttributeType[]	getAttributeTypes() AttributeTypes for this FeatureType, all attributes defined by this FeatureType and its super types define schema for feature instances.
VPFCoverage	getCoverage()
GeometryAttributeType	getDefaultGeometry() Gets the default geometry AttributeType.
java.lang.String	getDirectoryName()
java.lang.String	getFaccCode() The FACC code, a two-letter, 3-number code identifying the feature type
VPFFeatureClass	getFeatureClass()
java.util.List	getFileList() Returns a list of file objects
java.util.List	getJoinList()
java.net.URI	getNamespace() Gets the global schema namespace.
java.lang.String	getTypeName() Gets the type name for this schema.
boolean	hasAttributeType(java.lang.String xPath) This is only used twice in the whole geotools code base, and one of those is for a test, so we're removing it from the interface.
int	hashCode() Hascode based on namespace, typeName, attributes and ancestors.
boolean	isAbstract() Is this FeatureType an abstract type?
boolean	isDescendedFrom(FeatureType type) A convenience method for calling FeatureType f1; FeatureType f2; f1.isDescendedFrom(f2.getNamespace(), f2.getName()); Question: this method duplicates the information provided by getAncestors().
boolean	isDescendedFrom(java.net.URI nsURI, java.lang.String typeName) Test to determine whether this FeatureType is descended from the given FeatureType.

Methods inherited from class java.lang.Object

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

Constructor Detail

VPFFeatureType

public VPFFeatureType(VPFFeatureClass cFeatureClass,
                      Feature cFeature)

Constructor

Parameters:

cFeatureClass - The owning feature class

cFeature - A Feature from the char.vdt file with more detailed information for this feature type

VPFFeatureType

public VPFFeatureType(VPFFeatureClass cFeatureClass)

A constructor for feature types with no information in a char.vdt file.

Parameters:

cFeatureClass - The owning feature class

Method Detail

create

public Feature create(java.lang.Object[] attributes)
               throws IllegalAttributeException

Description copied from interface: FeatureType

Scheduled for removal in Geotools 2.2, please use FeatureFactory.

Creates a new feature, with a generated unique featureID. This is less than ideal, as a FeatureID should be persistant over time, generally created by a datasource. This method is more for testing that doesn't need featureID.

Specified by:

create in interface FeatureType

Parameters:

attributes - the array of attribute values

Returns:

The created feature

Throws:

IllegalAttributeException - if the FeatureType does not validate the attributes.

create

public Feature create(java.lang.Object[] attributes,
                      java.lang.String featureID)
               throws IllegalAttributeException

Description copied from interface: FeatureType

Scheduled for removal in Geotools 2.2, please use FeatureFactory.

Creates a new feature, with the proper featureID.

Specified by:

create in interface FeatureType

Parameters:

attributes - the array of attribute values.

featureID - the feature ID.

Returns:

the created feature.

Throws:

IllegalAttributeException - if the FeatureType does not validate the attributes.

duplicate

public Feature duplicate(Feature feature)
                  throws IllegalAttributeException

Description copied from interface: FeatureType

Create a duplicate of the provided feature, must delegate to an appropriate FeatureFactory create method.

The implementation is assumed to make use of AttributeType duplicate as required for a deep copy.

//@deprecated This method will be removed in 2.2, please use FeatureFactory obtained from FactoryFinder

Specified by:

duplicate in interface FeatureType

Parameters:

feature -

Returns:

a deep copy of feature

Throws:

IllegalAttributeException

find

public int find(AttributeType type)

Description copied from interface: FeatureType

Find the position of a given AttributeType.

Match is based on attribute type name, the resulting index may be used with getAttributeType( index ).

Specified by:

find in interface FeatureType

Parameters:

type - The type to search for.

Returns:

-1 if not found, a zero-based index if found.

getAncestors

public FeatureType[] getAncestors()

Description copied from interface: FeatureType

Obtain an array of this FeatureType's direct ancestors. Implementors should return a non-null array (may be of length 0).

• length 0 - a root FeatureType
• length 1 - singe inhieratance
• length 1+ - multiple inheiratance, order is not significant

GetAncestors() indicates *just* the direct parents of this FeatureType. It capures the inheirtance relationship from the OGC overview document.

Example Code:

 public FeatureType getAncestors()}
     return new FeatureType[]{ getSuper(), };
 }
 

Specified by:

getAncestors in interface FeatureType

Returns:

An array of ancestors.

getAttributeCount

public int getAttributeCount()

Description copied from interface: FeatureType

The number of attribues defined by this schema.

This method to allows access to the complete schema as defined by this FeatureType and its ancestors.

Notes:
• for FeatureType with no super type this count value is the the same as getAttributeTypes().length.

  Specified by:

  getAttributeCount in interface FeatureType

  Returns:

  number of distinct attributeTypes available, taking ancestors and taking overrides into account.

getAttributeType

public AttributeType getAttributeType(int position)

Description copied from interface: FeatureType

Gets the schema attributeType at the specified index.

The index is specified with respect to the entire Schema (as defined by this FeatureType and it's ancestors).

The index value should not be used with either:
• FeatureType.getAttributeTypes()[index] - as it defines only attributes contributed by this FeatureType
• Feature.getAttribute( index ) - as attributes order may or may not be in sequence

Specified by:

getAttributeType in interface FeatureType

Returns:

The attribute type at the specified position.

getAttributeType

public AttributeType getAttributeType(java.lang.String xPath)

Description copied from interface: FeatureType

Gets the attributeType at this xPath, if the specified attributeType does not exist then null is returned.

Question: it is unclear how this interacts with the complete schema defined by this FeatureType and its ancestors (in which a given xpath may refer to several AttributeTypes as restrictions are applied.

Perhaps this method should be restricted to a FlatFeatureType? Or should have the option of returning an array of matching AttributeType in order of inheiritence?

Specified by:

getAttributeType in interface FeatureType

Parameters:

xPath - XPath pointer to attribute type.

Returns:

AttributeType, or null if unavaialble

getAttributeTypes

public AttributeType[] getAttributeTypes()

Description copied from interface: FeatureType

AttributeTypes for this FeatureType, all attributes defined by this FeatureType and its super types define schema for feature instances.

The provided array of AttributeTypes should be considered as adding to (or overriding) the the AttribtueTypes defined by this FeatureTypes ancestors.

Note Well: Client code should not consider the index provided by the find( attName ) method as a valid index into the returned array.

Specified by:

getAttributeTypes in interface FeatureType

Returns:

Array of AttributeType describing this schema, array may be length 0, but should not be null

getCoverage

public VPFCoverage getCoverage()

Returns:

getDefaultGeometry

public GeometryAttributeType getDefaultGeometry()

Description copied from interface: FeatureType

Gets the default geometry AttributeType.

If the FeatureType has more one geometry it is up to the implementor to determine which geometry is the default. If working with multiple geometries it is best to get the attributeTypes and iterate through them, checking for instances of GeometryAttribtueType.

This should just be used a convenience method when it is known that the features do not have multiple geometries.

Specified by:

getDefaultGeometry in interface FeatureType

Returns:

The attribute type of the default geometry, which will contain the position.

getDirectoryName

public java.lang.String getDirectoryName()

Returns:

getFeatureClass

public VPFFeatureClass getFeatureClass()

Returns:

Returns the featureClass.

getFileList

public java.util.List getFileList()

Returns a list of file objects

Returns:

a List containing VPFFile objects

getJoinList

public java.util.List getJoinList()

Returns:

getNamespace

public java.net.URI getNamespace()

Description copied from interface: FeatureType

Gets the global schema namespace.

This is often used to record the schema prefix (not the URI) required when writing out this Feature using GML. The supporting application will need to be able to start the GMLWriter off with the correct URI information so everything makes sense.

The Registry interface provided by the data module provides an example of how to store associate FeatureType and namespace information. Please note that you may not have duplicate typeNames in the same Namespace.

Specified by:

getNamespace in interface FeatureType

Returns:

Namespace of schema

getTypeName

public java.lang.String getTypeName()

Description copied from interface: FeatureType

Gets the type name for this schema.

In GML this must be the element name of the Feature.

Specified by:

getTypeName in interface FeatureType

Returns:

The name of this feature type.

hasAttributeType

public boolean hasAttributeType(java.lang.String xPath)

Description copied from interface: FeatureType

This is only used twice in the whole geotools code base, and one of those is for a test, so we're removing it from the interface. If getAttributeType does not have the AttributeType it will just return null. Gets the number of occurrences of this attribute.

Question: the comment says we are removing this, but it is not depricated? And how the heck can the number of occurances out of a boolean.

Specified by:

hasAttributeType in interface FeatureType

Parameters:

xPath - XPath pointer to attribute type.

Returns:

Number of occurrences.

isAbstract

public boolean isAbstract()

Description copied from interface: FeatureType

Is this FeatureType an abstract type?

When true is returned instances of this Feature cannot be created, instead a child FeatureType must use this FeatureType as its ancestor.

Specified by:

isAbstract in interface FeatureType

Returns:

true if abstract, false otherwise.

isDescendedFrom

public boolean isDescendedFrom(FeatureType type)

Description copied from interface: FeatureType

A convenience method for calling

 FeatureType f1;
 FeatureType f2;
 f1.isDescendedFrom(f2.getNamespace(), f2.getName());
 

Question: this method duplicates the information provided by getAncestors().

Specified by:

isDescendedFrom in interface FeatureType

Parameters:

type - The type to compare to.

Returns:

true if descendant, false otherwise.

isDescendedFrom

public boolean isDescendedFrom(java.net.URI nsURI,
                               java.lang.String typeName)

Description copied from interface: FeatureType

Test to determine whether this FeatureType is descended from the given FeatureType. Think of this relationship likes the "extends" relationship in java.

Specified by:

isDescendedFrom in interface FeatureType

Parameters:

nsURI - The namespace URI to use.

typeName - The typeName.

Returns:

true if descendant, false otherwise.

getFaccCode

public java.lang.String getFaccCode()

The FACC code, a two-letter, 3-number code identifying the feature type

Returns:

Returns the FACC Code.

find

public int find(java.lang.String attName)

Description copied from interface: FeatureType

Find the position of an AttributeType which matches the given String.

This index may be used with getAttributeType( index ), the search space is the entire schema defined by this FeatureType and its ancestors.

Specified by:

find in interface FeatureType

Parameters:

attName - the name to look for

Returns:

-1 if not found, zero-based index otherwise

equals

public boolean equals(java.lang.Object obj)

Description copied from interface: FeatureType

FeatureType check based on namespace, typeName, attributes and ancestors.

Conceptually FeatureType equality is supped to indicate an exact match based AttributeType and Ancestors. The geotools models includes additional information of namespace and typename.

As far as the geotools data model is concerned any FeatureType implementation should be able to be subsituted for another. (An actually application may provided an implementation that provdes tracking of metadata such as creation history, or support for additional interfaces).

Required implementation:

A sample implementation is provided in FeatureTypes.equals( FeatureType, FeatureType ).

Questions:
Q: You may wonder why namespace and typeName are not enought?
A: Geotools often returns a "limitied" schema in response to a query where only a subset of the attributes are requested.
Q: Doesn't that still indicate the same schema?
A: Yes it kind of should, a GML application (such as GeoServer) has to actually follow the application schema and include attributes required by the schema (but not request by the query). This library is more lax in its treatment, and expects you to uses isDecendedFrom as required.

Specified by:

equals in interface FeatureType

hashCode

public int hashCode()

Description copied from interface: FeatureType

Hascode based on namespace, typeName, attributes and ancestors.

Hascode is always a matched set with an equals implementation, please see the javadocs for equals for a detailed discussion.

Specified by:

hashCode in interface FeatureType