netbeans.apache.org/src/content/wiki/DevFaqNodeSubclass.asciidoc

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= DevFaqNodeSubclass
:jbake-type: wiki
:jbake-tags: wiki, devfaq, needsreview
:jbake-status: published
:keywords: Apache NetBeans wiki DevFaqNodeSubclass
:description: Apache NetBeans wiki DevFaqNodeSubclass
:toc: left
:toc-title:
:syntax: true

=== Creating Node Subclasses

Nodes are useful for many things beyond just representing files.  If you just need a placeholder `Node`, you do not need a subclass - just instantiate an `AbstractNode` - despite its name, `AbstractNode` is not an abstract class.  For example:

[source,java]
----

AbstractNode nue = new AbstractNode (Children.LEAF);
nue.setDisplayName ("Please wait...");
nue.setIcon (Utilities.loadImage ("path/in/jar/to/image.gif"));
return nue;
----

If you are creating link:DevFaqWhatIsANode.asciidoc[Node]s, you will typically deal with one of four things

* link:http://bits.netbeans.org/dev/javadoc/org-openide-nodes/org/openide/nodes/AbstractNode.html[AbstractNode] - create a Node which represents anything you want - you will implement all its logic, provide children, etc.  Typically most logic goes in the Children object. 
* link:http://bits.netbeans.org/dev/javadoc/org-openide-nodes/org/openide/nodes/BeanNode.html[BeanNode] - a very convenient Node subclass, which can represent any JavaBean as a Node and expose its bean properties as Property objects that can be edited on the property sheet
* link:http://bits.netbeans.org/dev/javadoc/org-openide-nodes/org/openide/nodes/FilterNode.html[FilterNode] - a Node subclass that proxies another Node.  You can subclass this to take an existing Node (possibly representing a file on disk or in the link:DevFaqSystemFilesystem.asciidoc[system filesystem ] and keep most of its attributes, but provide different actions or display name or icons or properties
* link:http://bits.netbeans.org/dev/javadoc/org-openide-loaders/org/openide/loaders/DataNode.html[DataNode] - a Node subclass specific to editing files.  If you are writing a module that adds support for a new file type (such as `.svg` files), you will write a `DataNode` subclass to give files of that type icons, display names, and possibly provide access to the file's content

Note that if you just want to write context sensitive code, not provide your own Nodes, you may be able to do it without a dependency on the Nodes API, using link:DevFaqTrackGlobalSelection.asciidoc[Utilities.actionsGlobalContext()].

=== Apache Migration Information

The content in this page was kindly donated by Oracle Corp. to the
Apache Software Foundation.

This page was exported from link:http://wiki.netbeans.org/DevFaqNodeSubclass[http://wiki.netbeans.org/DevFaqNodeSubclass] , 
that was last modified by NetBeans user Tboudreau 
on 2010-01-24T05:48:37Z.


*NOTE:* This document was automatically converted to the AsciiDoc format on 2018-02-07, and needs to be reviewed.