Package com.luciad.models.features

Class FeatureModelPersistenceManager

java.lang.Object

com.luciad.models.features.FeatureModelPersistenceManager

All Implemented Interfaces:

AutoCloseable

public final class FeatureModelPersistenceManager
extends Object
implements AutoCloseable

This class can be used to save changes to an IFeatureModel's backend.

The main goal of this class it to give more control over when changes are persisted. An important difference between the updater and the FeatureModelPersistenceManager is the frequency at which they are used, with the FeatureModelPersistenceManager typically being used less often. In other words:

• The updater typically only makes in-memory changes. These can occur in a high frequency and can be executed fast.
• FeatureModelPersistenceManager can persist these in-memory changes. This is slower to execute, can require more resources (disk access for example), but can be performed at a lower frequency.

For example: when dragging a point from one location to another in an editor configured to update on any change, many small updates are done along the way. In contrast, a save typically only happens when the editing is finished.

A FeatureModelPersistenceManager can be accessed through the model using IFeatureModel#getPersistenceManager.

See this article for more information.

Since:

2023.1

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final class	FeatureModelPersistenceManager.Builder	IFeatureModel implementations that have support for saving changes can use this class to create a FeatureModelPersistenceManager instance.

Method Summary

Modifier and Type	Method	Description
void	close()
void	discardChanges()	Discards the unsaved (in-memory) changes of the IFeatureModel, restoring the IFeatureModel's state back to that of its backend.
boolean	equals(Object other)
protected void	finalize()
List<@NotNull FeatureChange>	getChanges()	Returns the list of all unsaved (in-memory) changes if the IFeatureModel.
int	hashCode()
static FeatureModelPersistenceManager.Builder	newBuilder()	Returns a new FeatureModelPersistenceManager builder.
FeatureSaveErrorInfo	saveChanges()	Save the in-memory changes in the IFeatureModel's backend (for example a file or database).

Methods inherited from class java.lang.Object

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

Method Details

finalize

protected void finalize()

Overrides:

finalize in class Object

close

public void close()

Specified by:

close in interface AutoCloseable

newBuilder

@NotNull
public static FeatureModelPersistenceManager.Builder newBuilder()

Returns a new FeatureModelPersistenceManager builder.

Returns:

a new FeatureModelPersistenceManager builder.

saveChanges

@Nullable
public FeatureSaveErrorInfo saveChanges()

Save the in-memory changes in the IFeatureModel's backend (for example a file or database).

Typically, calling this method shouldn't modify the in-memory state of the model. So the feature model will not send out events through its observers. In some cases however (depending on the model implementation), feature changes can occur while changes are saved. In that case, the model's observers need to be notified of those changes.

Returns:

null on success, or error information on failure.

discardChanges

public void discardChanges()

Discards the unsaved (in-memory) changes of the IFeatureModel, restoring the IFeatureModel's state back to that of its backend.

All observers will be notified with a FeatureModelEvent containing the FeatureChanges necessary to go back to the backend's state.

getChanges

@NotNull
public List<@NotNull FeatureChange> getChanges()

Returns the list of all unsaved (in-memory) changes if the IFeatureModel.

That is, the changes that need to be saved to the IFeatureModel's backend to persist all in-memory changes. Multiple updates to the same feature will be condensed to a single FeatureChange.

Returns:

the list of all unsaved (in-memory) changes if the IFeatureModel.

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(@Nullable
 Object other)

Overrides:

equals in class Object