Package net.sf.basedb.core

Class FastAnnotationLoader<T>

java.lang.Object

net.sf.basedb.core.FastAnnotationLoader<T>

Type Parameters:

T - The type of values for the annotation

public class FastAnnotationLoader<T>
extends Object

Implements an API for simple and fast loading of annotation values optimized for situations when a single annotation is needed for many (=thousands) of items. The regular annotation API is typically very slow and requires multiple SQL queries for each annotation. The SnapshotManager API is typically faster, but only if the annotations have already been cached. This API have limited filtering capabilities and can be used for reading only, but it can be combined with the AnnotationBatcher API for updating annotations. The result is returned as an iterator with each entry corresponding to a single annotation value. The values are not sorted in any particular order. If the annotation type allows multiple values each value is returned as separate iterator entries in no particular order. If the annotation type supports project-specific values, only default values and values for the current project are returned.

Since:

3.19.10

See Also:

• AnnotationType.getFastLoader(DbControl)

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	FastAnnotationLoader.FastAnnotation<T>	Holds information about a single annotation value.
(package private) static class	FastAnnotationLoader.FastIterator<T>	Iterator implementation that splits the query into multiple calls depending on the max number of parameters that can be used in a query.

Field Summary

Fields

Modifier and Type	Field	Description
private final DbControl	dc
private boolean	includeDefault
private int	projectId
private final AnnotationType	type

Constructor Summary

Constructors

Constructor	Description
FastAnnotationLoader(DbControl dc, AnnotationType type)

Method Summary

Modifier and Type	Method	Description
Iterator<FastAnnotationLoader.FastAnnotation<T>>	load(Collection<? extends Annotatable> items)	Load the annotation values for all items in the given collection.
Iterator<FastAnnotationLoader.FastAnnotation<T>>	load(Iterator<? extends Annotatable> items)	Load the annotation values for all items returned by the given iterator.
Iterator<FastAnnotationLoader.FastAnnotation<T>>	load(ItemQuery<? extends Annotatable> query)	Load the annotation values for all items returned by the query.
void	setIncludeDefault(boolean includeDefault)	If the annotation type supports project-specific annotations this method can be used to control which values that are loaded.
void	setProject(Project p)	If the annotation type supports project-specific annotations this method can be used to control which values that are loaded.

Methods inherited from class java.lang.Object

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

Field Details

dc

private final DbControl dc

type

private final AnnotationType type

projectId

private int projectId

includeDefault

private boolean includeDefault

Constructor Details

FastAnnotationLoader

FastAnnotationLoader(DbControl dc,
 AnnotationType type)

Method Details

setProject

public void setProject(Project p)

If the annotation type supports project-specific annotations this method can be used to control which values that are loaded. The default setting is to load default values and values for the currently active project.

Parameters:

p - The project that values should belong to, or null to not load any project-specific values

setIncludeDefault

public void setIncludeDefault(boolean includeDefault)

If the annotation type supports project-specific annotations this method can be used to control which values that are loaded. The default setting is to load default values and values for the currently active project.

Parameters:

includeDefault - TRUE to include default values, FALSE to not include them

load

public Iterator<FastAnnotationLoader.FastAnnotation<T>> load(ItemQuery<? extends Annotatable> query)

Load the annotation values for all items returned by the query. This method is typically faster than the load(Collection) method since the AbstractEntityQuery.idList(DbControl) is used to only load item ids and not full items.

load

public Iterator<FastAnnotationLoader.FastAnnotation<T>> load(Collection<? extends Annotatable> items)

Load the annotation values for all items in the given collection. Note! All items in the collection must be of the same type.

load

public Iterator<FastAnnotationLoader.FastAnnotation<T>> load(Iterator<? extends Annotatable> items)

Load the annotation values for all items returned by the given iterator. Note! All items returned by the iterator must be of the same type.