uk.ac.starlink.ttools.cone

Class JdbcConer

java.lang.Object

uk.ac.starlink.ttools.cone.JdbcConer

All Implemented Interfaces:

Coner

public class JdbcConer
extends Object
implements Coner

Coner implementation which works by performing SELECT statements over a JDBC database connection.

Since:

15 Aug 2007

Author:

Mark Taylor

Constructor Summary

Constructors

Constructor and Description
JdbcConer() Constructor.

Method Summary

Modifier and Type	Method and Description
void	configureParams(Environment env, Parameter<?> srParam) Provides this object with a chance to perform custom configuration on certain general cone search parameters.
ConeSearcher	createSearcher(Environment env, boolean bestOnly) Returns a searcher object which can perform the actual cone searches as configured by this object's parameters.
Coverage	getCoverage(Environment env) Returns a coverage object suitable for use with the cone search service configured by this object's parameters.
Parameter<?>[]	getParameters() Returns any configuration parameters associated with this object.
String	getSkySystem() Returns the empty string.
boolean	useDistanceFilter(Environment env) Indicates whether the result table generated by the created ConeSearcher object should be subjected to additional filtering to ensure that only rows in the specified search radius are included in the final output.

Methods inherited from class java.lang.Object

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

Constructor Detail

JdbcConer

public JdbcConer()

Constructor.

Method Detail

getSkySystem

public String getSkySystem()

Returns the empty string. No particular coordinate system is mandated by this object.

Specified by:

getSkySystem in interface Coner

Returns:

ecliptic coordinate system name

getParameters

public Parameter<?>[] getParameters()

Description copied from interface: Coner

Returns any configuration parameters associated with this object.

Specified by:

getParameters in interface Coner

Returns:

parameter array

configureParams

public void configureParams(Environment env,
                            Parameter<?> srParam)

Description copied from interface: Coner

Provides this object with a chance to perform custom configuration on certain general cone search parameters. If no customisation is required, no action need be taken. This will be called during the parameter acquisition phase, before the relevant parameters have been interrogated. Since the execution environment is given however, it will not be called during automatic document generation.

Specified by:

configureParams in interface Coner

Parameters:

env - execution environment

srParam - search radius parameter

useDistanceFilter

public boolean useDistanceFilter(Environment env)

Description copied from interface: Coner

Indicates whether the result table generated by the created ConeSearcher object should be subjected to additional filtering to ensure that only rows in the specified search radius are included in the final output.

Specified by:

useDistanceFilter in interface Coner

Parameters:

env - execution environment

Returns:

true iff post-query filtering on distance is to be performed

createSearcher

public ConeSearcher createSearcher(Environment env,
                                   boolean bestOnly)
                            throws TaskException

Description copied from interface: Coner

Returns a searcher object which can perform the actual cone searches as configured by this object's parameters. If the bestOnly flag is set, then only the best match is required. The implementation may use this as a hint if it helps efficiency, but is not obliged to return single-row tables, since extraneous rows will be filtered out later. Similarly any rows which do not actually match the given criteria will be filtered out later, so it is not an error to return too many rows.

Specified by:

createSearcher in interface Coner

Parameters:

env - execution environment

bestOnly - true iff only the best match will be used

Throws:

TaskException

getCoverage

public Coverage getCoverage(Environment env)

Description copied from interface: Coner

Returns a coverage object suitable for use with the cone search service configured by this object's parameters.

Specified by:

getCoverage in interface Coner

Parameters:

env - execution environment

Returns:

coverage footprint, or null