org.apache.jackrabbit.oak.plugins.migration

Class NodeStateCopier

java.lang.Object

org.apache.jackrabbit.oak.plugins.migration.NodeStateCopier

public class NodeStateCopier
extends Object

The NodeStateCopier and NodeStateCopier.Builder classes allow recursively copying a NodeState to a NodeBuilder.
The copy algorithm is optimized for copying nodes between two different NodeStore instances, i.e. where comparing NodeStates is imprecise and/or expensive.
The algorithm does a post-order traversal. I.e. it copies changed leaf-nodes first.
The work for a traversal without any differences between source and target is equivalent to the single execution of a naive equals implementation.
Usage: For most use-cases the Builder API should be preferred. It allows setting includePaths, excludePaths and mergePaths.
Include paths: if include paths are set, only these paths and their sub-trees are copied. Any nodes that are not within the scope of an include path are implicitly excluded.
Exclude paths: if exclude paths are set, any nodes matching or below the excluded path are not copied. If an excluded node does exist in the target, it is removed (see also merge paths). Exclude fragments: if exclude fragments are set, nodes with names matching any of the fragments (and their subtrees) are not copied. If an excluded node does exist in the target, it is removed. Merge paths: if merge paths are set, any nodes matching or below the merged path will not be deleted from target, even if they are missing in (or excluded from) the source.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	NodeStateCopier.Builder The NodeStateCopier.Builder allows configuring a NodeState copy operation with includePaths, excludePaths and mergePaths.

Method Summary

Modifier and Type	Method and Description
static NodeStateCopier.Builder	builder() Create a NodeStateCopier.Builder.
static boolean	copyNodeStore(@NotNull NodeStore source, @NotNull NodeStore target) Shorthand method to copy one NodeStore to another.
static boolean	copyProperties(NodeState source, NodeBuilder target) Copies all changed properties from the source NodeState to the target NodeBuilder instance.

Methods inherited from class java.lang.Object

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

Method Detail

builder

public static NodeStateCopier.Builder builder()

Create a NodeStateCopier.Builder.

Returns:

a NodeStateCopier.Builder

See Also:

NodeStateCopier.Builder

copyNodeStore

public static boolean copyNodeStore(@NotNull
                                    @NotNull NodeStore source,
                                    @NotNull
                                    @NotNull NodeStore target)
                             throws CommitFailedException

Shorthand method to copy one NodeStore to another. The changes in the target NodeStore are automatically persisted.

Parameters:

source - NodeStore to copy from.

target - NodeStore to copy to.

Returns:

true if the target has been modified

Throws:

CommitFailedException - if the operation fails

See Also:

NodeStateCopier.Builder.copy(NodeStore, NodeStore)

copyProperties

public static boolean copyProperties(NodeState source,
                                     NodeBuilder target)

Copies all changed properties from the source NodeState to the target NodeBuilder instance.

Parameters:

source - The NodeState to copy from.

target - The NodeBuilder to copy to.

Returns:

Whether changes were made or not.