Michael Dürig created OAK-275:
---------------------------------
Summary: Introduce TreeLocation interface
Key: OAK-275
URL: https://issues.apache.org/jira/browse/OAK-275
Project: Jackrabbit Oak
Issue Type: Improvement
Components: core
Reporter: Michael Dürig
In order to address the issues revolving around access control (i.e OAK-212,
OAK-214, OAK-218, OAK-220, OAK-226,...) I'd like to introduce a new interface
{{TreeLocation}}:
{code}
/**
* A {@code TreeLocation} denotes a location inside a tree.
* It can either refer to a inner node (that is a {@link
org.apache.jackrabbit.oak.api.Tree})
* or to a leaf (that is a {@link org.apache.jackrabbit.oak.api.PropertyState}).
* {@code TreeLocation} instances provide methods for navigating trees. {@code
TreeLocation}
* instances are immutable and navigating a tree always results in new {@code
TreeLocation}
* instances. Navigation never fails. Errors are deferred until the underlying
item itself is
* accessed. That is, if a {@code TreeLocation} points to an item which does
not exist or
* is unavailable otherwise (i.e. due to access control restrictions) accessing
the tree
* will return {@code null} at this point.
*/
public interface TreeLocation {
/**
* Navigate to the parent
* @return a {@code TreeLocation} for the parent of this location.
*/
@Nonnull
TreeLocation getParent();
/**
* Navigate to a child
* @param name name of the child
* @return a {@code TreeLocation} for a child with the given {@code name}.
*/
@Nonnull
TreeLocation getChild(String name);
/**
* Get the underlying {@link org.apache.jackrabbit.oak.api.Tree} for this
{@code TreeLocation}.
* @return underlying {@code Tree} instance or {@code null} if not
available.
*/
@CheckForNull
Tree getTree();
/**
* Get the underlying {@link org.apache.jackrabbit.oak.api.PropertyState}
for this {@code TreeLocation}.
* @return underlying {@code PropertyState} instance or {@code null} if
not available.
*/
@CheckForNull
PropertyState getProperty();
}
{code}
Such an interface would decouple navigation from the tree itself while at the
same time unifying node and property access. This allows us to enforce access
control restriction on the tree itself while still being able to access items
which we are "unlinked" by access control restrictions. In addition unification
of node and property access will simplify the code in many places. Finally
{{TreeLocations}} might better encapsulate the resolution of a location in a
tree to the actual tree. This is something which currently done in
{{Node/PropertyDelegate.resolve}} but always bothered me as too ad-hoc.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators:
https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira
