org.geotools.data.vpf
Class VPFDataStoreFactory

java.lang.Object
  extended by org.geotools.data.vpf.VPFDataStoreFactory
All Implemented Interfaces:
DataAccessFactory, DataStoreFactorySpi, Factory

public class VPFDataStoreFactory
extends java.lang.Object
implements DataStoreFactorySpi

Class VPFDataSourceFactory.java is responsible for constructing appropriate VPFDataStore (actually VPFLibrary) objects. VPFDataStoreFactory - factory for VPFLibrary - factory for VPFCoverage - factory for VPFFeatureClass - implements FeatureType by delegation to contained DefaultFeatureType - contains VPFFiles - retrieves VPFColumns from VPFFiles for use in constructing DefaultFeatureType - contains joins (column pairs) - factory for VPFFeatureType - implements FeatureType by delegation to contained VPFFeatureClass VPFFile - contains VPFInputStream - factory for VPFColumn - implements AttributeType by delegation to contained DefaultFeatureType

Created: Fri Mar 28 15:54:32 2003

Version:
2.1.0
Author:
Artur Hefczyc, Knut-Erik Johnsen, Project OneMap, Chris Holmes, Fulbright

Nested Class Summary
 
Nested classes/interfaces inherited from interface org.geotools.data.DataAccessFactory
DataAccessFactory.Param
 
Field Summary
static DataAccessFactory.Param DIR
          A parameter which is the directory containing the LHT file
protected static java.util.logging.Logger LOGGER
          The logger for the vpf module.
static DataAccessFactory.Param NAMESPACEP
           
 
Constructor Summary
VPFDataStoreFactory()
          Default Constructor
 
Method Summary
 boolean canProcess(java.util.Map params)
          Test to see if this factory is suitable for processing the data pointed to by the params map.
 DataStore createDataStore(java.util.Map params)
          Construct a live data source using the params specifed.
 DataStore createNewDataStore(java.util.Map params)
           
 java.lang.String getDescription()
          Describe the nature of the datasource constructed by this factory.
 java.lang.String getDisplayName()
          Name suitable for display to end user.
 java.util.Map getImplementationHints()
          Returns the implementation hints.
 DataAccessFactory.Param[] getParametersInfo()
          MetaData about the required Parameters (for createDataStore).
 boolean isAvailable()
          Test to see if the implementation is available for use.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

LOGGER

protected static final java.util.logging.Logger LOGGER
The logger for the vpf module.


DIR

public static final DataAccessFactory.Param DIR
A parameter which is the directory containing the LHT file


NAMESPACEP

public static final DataAccessFactory.Param NAMESPACEP
Constructor Detail

VPFDataStoreFactory

public VPFDataStoreFactory()
Default Constructor

Method Detail

getDisplayName

public java.lang.String getDisplayName()
Description copied from interface: DataAccessFactory
Name suitable for display to end user.

A non localized display name for this data store type.

Specified by:
getDisplayName in interface DataAccessFactory
Returns:
A short name suitable for display in a user interface.

getDescription

public java.lang.String getDescription()
Description copied from interface: DataAccessFactory
Describe the nature of the datasource constructed by this factory.

A non localized description of this data store type.

Specified by:
getDescription in interface DataAccessFactory
Returns:
A human readable description that is suitable for inclusion in a list of available datasources.

canProcess

public boolean canProcess(java.util.Map params)
Description copied from interface: DataAccessFactory
Test to see if this factory is suitable for processing the data pointed to by the params map.

If this datasource requires a number of parameters then this mehtod should check that they are all present and that they are all valid. If the datasource is a file reading data source then the extentions or mime types of any files specified should be checked. For example, a Shapefile datasource should check that the url param ends with shp, such tests should be case insensative.

Specified by:
canProcess in interface DataAccessFactory
Parameters:
params - The full set of information needed to construct a live data source.
Returns:
booean true if and only if this factory can process the resource indicated by the param set and all the required params are pressent.

createDataStore

public DataStore createDataStore(java.util.Map params)
                          throws java.io.IOException
Description copied from interface: DataStoreFactorySpi
Construct a live data source using the params specifed.

You can think of this as setting up a connection to the back end data source.

Magic Params: the following params are magic and are honoured by convention by the GeoServer and uDig application.

When we eventually move over to the use of OpperationalParam we will have to find someway to codify this convention.

Specified by:
createDataStore in interface DataAccessFactory
Specified by:
createDataStore in interface DataStoreFactorySpi
Parameters:
params - The full set of information needed to construct a live data store. Typical key values for the map include: url - location of a resource, used by file reading datasources. dbtype - the type of the database to connect to, e.g. postgis, mysql
Returns:
The created DataStore, this may be null if the required resource was not found or if insufficent parameters were given. Note that canProcess() should have returned false if the problem is to do with insuficent parameters.
Throws:
java.io.IOException - if there were any problems setting up (creating or connecting) the datasource.

createNewDataStore

public DataStore createNewDataStore(java.util.Map params)
                             throws java.io.IOException
Specified by:
createNewDataStore in interface DataStoreFactorySpi
Throws:
java.io.IOException

getParametersInfo

public DataAccessFactory.Param[] getParametersInfo()
Description copied from interface: DataAccessFactory
MetaData about the required Parameters (for createDataStore).

Interpretation of FeatureDescriptor values:

This should be the same as:


 Object params = factory.getParameters();
 BeanInfo info = getBeanInfo( params );

 return info.getPropertyDescriptors();
 

Specified by:
getParametersInfo in interface DataAccessFactory
Returns:
Param array describing the Map for createDataStore

isAvailable

public boolean isAvailable()
Description copied from interface: DataAccessFactory
Test to see if the implementation is available for use. This method ensures all the appropriate libraries to construct the DataAccess are available.

Most factories will simply return true as GeoTools will distribute the appropriate libraries. Though it's not a bad idea for DataStoreFactories to check to make sure that the libraries are there.

OracleDataStoreFactory is an example of one that may generally return false, since GeoTools can not distribute the oracle jars. (they must be added by the client.)

One may ask how this is different than canProcess, and basically available is used by the DataStoreFinder getAvailableDataStore method, so that DataStores that can not even be used do not show up as options in gui applications.

Specified by:
isAvailable in interface DataAccessFactory
Returns:
true if and only if this factory has all the appropriate jars on the classpath to create DataStores.

getImplementationHints

public java.util.Map getImplementationHints()
Returns the implementation hints. The default implementation returns en empty map.

Specified by:
getImplementationHints in interface Factory
Returns:
The map of hints, or an empty map if none.


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