org.apache.jackrabbit.oak.spi.observation

Class ChangeSet

java.lang.Object

org.apache.jackrabbit.oak.spi.observation.ChangeSet

public final class ChangeSet
extends java.lang.Object

A ChangeSet is a collection of items that have been changed as part of a commit. A ChangeSet is immutable and built by a ChangeSetBuilder.

Those items are parent paths, parent node names, parent node types and (child) properties. 'Changed' refers to any of add, remove, change (where applicable).

A ChangeSet is piggybacked on a CommitInfo in the CommitContext and can be used by (downstream) Observers for their convenience.

To limit memory usage, the ChangeSet has a limit on the number of items, each, that it collects. If one of those items reach the limit this is called an 'overflow' and the corresponding item type is marked as having 'overflown'. Downstream Observers should thus check if a particular item has overflown or not - this is indicated with null as the return value of the corresponding getters (while empty means: not overflown but nothing changed of that type).

Also, the ChangeSet carries a 'maxPathDepth' which is the depth of the path up until which paths have been collected. Thus any path that is longer than this 'maxPathDepth' will be cut off and only reported up to that max depth. Downstream Observers should thus inspect the 'maxPathDepth' and compare actual path depths with it in order to find out if any child paths have been cut off.

Naming: note that path, node name and node types all refer to the *parent* of a change. While properties naturally are leafs.

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	COMMIT_CONTEXT_OBSERVATION_CHANGESET

Method Summary

Modifier and Type	Method and Description
boolean	anyOverflow()
java.lang.String	asString()
boolean	doesHitMaxPathDepth()
boolean	equals(java.lang.Object o)
static ChangeSet	fromString(java.lang.String json)
@Nullable java.util.Set<java.lang.String>	getAllNodeTypes()
int	getMaxPrefilterPathDepth()
@Nullable java.util.Set<java.lang.String>	getParentNodeNames()
@Nullable java.util.Set<java.lang.String>	getParentNodeTypes()
@Nullable java.util.Set<java.lang.String>	getParentPaths()
@Nullable java.util.Set<java.lang.String>	getPropertyNames()
int	hashCode()
java.lang.String	toString()

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Field Detail

COMMIT_CONTEXT_OBSERVATION_CHANGESET

public static final java.lang.String COMMIT_CONTEXT_OBSERVATION_CHANGESET

See Also:

Constant Field Values

Method Detail

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

doesHitMaxPathDepth

public boolean doesHitMaxPathDepth()

getParentPaths

@Nullable
public @Nullable java.util.Set<java.lang.String> getParentPaths()

getParentNodeNames

@Nullable
public @Nullable java.util.Set<java.lang.String> getParentNodeNames()

getParentNodeTypes

@Nullable
public @Nullable java.util.Set<java.lang.String> getParentNodeTypes()

getPropertyNames

@Nullable
public @Nullable java.util.Set<java.lang.String> getPropertyNames()

getMaxPrefilterPathDepth

public int getMaxPrefilterPathDepth()

getAllNodeTypes

@Nullable
public @Nullable java.util.Set<java.lang.String> getAllNodeTypes()

anyOverflow

public boolean anyOverflow()

equals

public boolean equals(java.lang.Object o)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

asString

public java.lang.String asString()

fromString

public static ChangeSet fromString(java.lang.String json)