Java Doc for Hints.java in  » GIS » GeoTools-2.4.1 » org » geotools » factory » Java Source Code / Java DocumentationJava Source Code and Java Documentation

 CoordinateOperationFactory myFactory = &hellip
 Hints hints = new Hints(Hints.
 , myFactory);
 AbstractProcessor processor = new DefaultProcessor(hints);
 

Any hint mentioned by this class is considered to be API, failure to make use of a hint by a GeoTools factory implementation is considered a bug (as it will prevent the use of this library for application specific tasks).

When hints are used in conjuction with the we have the complete geotools plugin system. By using hints to allow application code to effect service discovery we allow client code to retarget the geotools library for their needs.
since:
   2.1
version:
   $Id: Hints.java 29443 2008-02-25 10:04:01Z jgarnett $
author:
   Martin Desruisseaux
author:
   Jody Garnett

This hint is treated as an absolute LIMIT for AbstractAuthorityMediator instances such as as HsqlDialectEpsgMediator.

This hint is treated as a recommendation for AbstractAuthorityMediator instances such as HsqlDialectEpsgMediator.

Filenames in the supplied directory should be of the form authority.properties where authority is the authority name space to use.

• String - used with JNDI to locate datasource.

This hint shall be passed to the (...) method.

This hint shall be passed to the (...) method.

Some operation when called on a that is the non-geophysics view of another grid coverage try to go back to the latter before executing even if they could execute fine without doing so.

This hint is treated as an absolute LIMIT for AbstractAuthorityMediator instances such as as HsqlDialectEpsgMediator. As such this will be the absolute limit on the number of database connections the mediator will make use of. When non-positive there is no limit to the number of connections used.

When this limit it reached, code will be forced to block while waiting for a connection to become available.
since:
   2.4

This hint is treated as a recommendation for AbstractAuthorityMediator instances such as HsqlDialectEpsgMediator. As such this will control the number of connections the mediator is comfortable having open.

If AUTHORITY_MAX_ACTIVE is set to 20, up to twenty connections will be used during heavy load. If the AUTHORITY_MAX_IDLE is set to 10, connections will be immediately reclaimed until only 10 are open.

When the amount of time specified by AUTHORITY_IDLE_WAIT Max idle controls the maximum number of objects that can sit idle in the pool at any time. When negative, there is no limit to the number of objects that may be idle at one time.
since:
   2.4

• "weak" for holding values through . This option do not actually cache the objects since the garbage collector cleans weak references aggressively, but it allows sharing the instances already created and still in use.
• "all" for holding values through strong references.
• "none" for disabling the cache.

Filenames in the supplied directory should be of the form authority.properties where authority is the authority name space to use. For example the file contains extra CRS to add as new EPSG codes.

To set the directory on the command line:

 -D
 =path
 

• String - used with JNDI to locate datasource. This hint has no effect if there is no setup.
• - used as is.
• missing - default to .

To set on the command line:

 -D
 =jndiReference
 

Example: In order to apply the (longitude,latitude) axis order to "http://www.opengis.net/" and "urn:ogc" name spaces in addition to EPSG, use the following hints:

hints.put(FORCE_LONGITUDE_FIRST_AXIS_ORDER, Boolean.TRUE); hints.put(FORCE_AXIS_ORDER_HONORING, "http, urn");

This hint shall be passed to the (...) method. Whatever this hint is supported or not is authority dependent. In the default Geotools configuration, this hint is supported for the "EPSG" authority.

If this hint is not provided, then the default value depends on many factors including and plugins available in the classpath. In Geotools implementation, the default value is usually Boolean.FALSE FALSE with one exception: If the system property is set to true , then the default value is true at least for the .

If both the above-cited system property and this hint are provided, then this hint has precedence. This allow axis order control on a data store basis, and keep the system-wide property as the default value only for cases where axis order is unspecified.

To set on the command line:

 -D
 =longitudeFirst
 

This hint shall be passed to the (...) method. Whatever this hint is supported or not is authority dependent.
See Also:   org.geotools.referencing.FactoryFinder.getCSFactory
See Also:   org.geotools.referencing.FactoryFinder.getCRSFactory
See Also:   org.geotools.referencing.factory.OrderedAxisAuthorityFactory
since:
   2.3

This hint shall be passed to the (...) method. Whatever this hint is supported or not is authority dependent.
See Also:   org.geotools.referencing.FactoryFinder.getCSFactory
See Also:   org.geotools.referencing.FactoryFinder.getCRSFactory
See Also:   org.geotools.referencing.factory.OrderedAxisAuthorityFactory
since:
   2.3

Some operation when called on a that is the non-geophysics view of another grid coverage try to go back to the latter before executing even if they could execute fine without doing so. The rationale behind this is that the non-geophysics view is just the rendered version of a coverage, hence operations should be applied onto the geophysics companion.

However, in some cases like when doing pure rendering of photographic images, we might want to force this operations to work on the non-geophysics view directly, even performing color expansions as needed. This can be accomplished by setting this hint to true . Be aware that interpolations in non-photographic images (i.e. a colormap like a Sea Surface Temperature image) after color expansions may produce wrong colors.
since:
   2.4org.geotools.coverage.grid.ViewType PROCESS_ON_VISUAL_VIEW

Note: We recommand to avoid the "jpeg" codec for grid coverages.
See Also:   org.geotools.coverage.FactoryFinder.getGridCoverageFactory
since:
   2.3

This method is intended for use with Java5: new Hints( Hints.BUFFER_LIMIT,1,Hints.BUFFER_POLICY,"weak" )
Parameters:
  pairs - Key value pairs

This method is invoked automatically the first time it is needed. It usually don't need to be invoked explicitly, except if the changed. The scan may not be performed immediately, but rather when needed at some later stage.
since:
   2.4