Creating Custom Node Type in JCR

In this blogpost, I’ll talk about the various ways of creating the Custom Node Type and deploying it across multiple instances. We’ll be using AEM 5.6.1 as our CQ server.

A. Creating and Registering the Custom Nodetype 

There are broadly following three ways of creating custom node types.

  1. Using Node Type Administration console.
  2. Programmatically
  3. Using Package Manager

We’ll discuss them one by one :

  1. Using Node Type Administration Console 
  • Using CND files.

The Compact Namespace and Node Type Definition (CND) notation provides a compact standardized syntax for defining node types and making namespace declarations. The notation is intended both for documentation and for programmatically registering node types. Existing documentation can be followed for creating the CND file.

Go to Node Type Administration console, click on Import  Node Type, copy/paste the CND file in the textarea, keep “Automatically register nodetype” checkbox and “Automatically register defined namespaces” checked. Click on submit and your custom node type will be registered.

  • Without using CND files

Go to Node Type Administration console,click on Create Node Type and enter the details about Node Name , child Node defintions , property definitions , supertypes etc. Click on the [Register Node Type] link at the bottom of the page to register this newly created Node type. Check the nodetype in Node type Administration console.

2. Programmatically

We can register the nodetype programmatically as well.

  • Using CND file.

We can use JCR Commons CndImporter to register it. Following is the code snippet to regsiter it. Create a CND file say nodetypes.cnd having the definition of the new node type. Make this file as a part of the bundle.

  • Without using CND file.

We can use JCR API to create a new node type and register it. Following is the code snippet to register it.


session = slingRepository.loginAdministrative(null); 

NodeTypeManager manager = (NodeTypeManager)session.getWorkspace().
getNodeTypeManager();
NamespaceRegistry ns=session.getWorkspace().getNamespaceRegistry();
ns.registerNamespace("cp","https://codepearlz.wordpress.com/CustomNode");

// Create node type
NodeTypeTemplate nodeTypeTemplate = manager.createNodeTypeTemplate();
nodeTypeTemplate.setName("cp:testNodeType");
// Create a new property PropertyDefinitionTemplate
customProperty1 = manager.createPropertyDefinitionTemplate();
customProperty1.setName("cp:Name");
customProperty1.setRequiredType(PropertyType.STRING); PropertyDefinitionTemplate
customProperty2 = manager.createPropertyDefinitionTemplate();
customProperty2.setName("cp:City");
customProperty2.setRequiredType(PropertyType.STRING);
// Add property to node type
nodeTypeTemplate.getPropertyDefinitionTemplates().add(customProperty1);
nodeTypeTemplate.getPropertyDefinitionTemplates().add(customProperty2);
/* Register node type */
manager.registerNodeType(nodeTypeTemplate, true); session.save();

3. Using Package Manager

We can register node type via package manager as well . In Package Manager, upload a CQ package containing custom nodetypes.cnd  and install it. Check that the custom nodetypes are registered in Node Type Administration console.

Troubleshoot : 

    • After registering the nodetype, make sure it is visible in Node Type Administration console. If not registered, check the error.log for more insight.
    • CND file should be in proper format to avoid unwanted errors.
    • Java 7 introduced a stricter verification and changed the class format a bit — to contain a stack map, used to verify that code is correct. If you are using java 7, pass these parameter -XX:MaxPermSize=512m -Xmx1520m -XX:-UseSplitVerifier while starting the instance from command line. Refer this link for more details.

B. Deploying the Custom Nodetype across multiple instances

If we have enabled clustering, then our multiple author and publish instances will be running on separate machines. We would want the new node type to be visible in all the instances. It can be  done via two ways :

  1. If we are programmatically registering the new node type, then deploying the bundle will simply make it visible across all the instances.
  2. Whenever a new node type gets registered in repository, three files gets updated . custom_nodetypes.xml at <CQ author instance directory>/crx-quickstart/repository/repository/nodetypes  will contain the definition of new node type. ns_idx.properties and ns_reg.properties at <CQ author instance directory>/crx-quickstart/repository/repository/namespaces will have the details of the new namespaces added. Copy/Pasting these files to all the instances at the specified location will make it visible. Note that this will require an instance restart.

Hope it helps !! 🙂

Debugging in AEM

While working on one of a complex requirements in our project, we felt the need to continuously analyze the flow. Though, logs are of good help but we wanted to analyze the complete flow . In this scenario, debugging feature in IDE becomes very handy. Software Stack being used : 

  • CQ Server : AEM 5.6.1
  • IDE : IntelliJIdea 12.0

First We need to start our CQ instance in debug mode. We can do so by starting the AEM in debug mode by running the following command :

 java -jar cq5-author-4502.jar -fork -forkargs -- -Xdebug -Xrunjdwp:transport=dt_socket,address=59865,suspend=n,server=y -Xmx1520m -XX:MaxPermSize=512m -XX:-UseSplitVerifier 

We need to first open the socket from where all the JVM communication will happen. We need to specify the port number while starting the instance. Socket specifies the entry point for all the communication that happens in JVM. Every communication will happen via Socket. In above command, address=59865  is creating the socket for us. In IDE, we need to setup a remote connection for CQ and specify the same port no as mentioned while starting CQ. Follow the below steps to setup a remote connection in IntelliJIdea.

  1. Go to Run panel (top of the window) and select Edit configuration.
  2. Select Defaults and click on “+” to add new configuration. List of all the options will appear. Select “Remote”  from that list.
  3. Enter the details in the window as per your need. Specify the same port number which was used while starting the CQ instance in debug mode.
  4. Click on “OK” to save the configuration.

Below is the screenshot for the reference.

debug

Add breakpoints in the java files which you want to debug by double clicking on the line and start newly created configuration in Debug mode.

Troubleshooting :

1. While starting the AEM instance, make sure JVM has enough heap size for running CQ server, otherwise it will fork the JVM and parameters will not be passed to the forked jvm. Use -fork -forkargs – option to ensure that the command line parameters gets passed to the jvm.

2. If you are using java 7 , make sure to specify the -XX:-UseSplitVerifier parameter to avoid the unwanted strict verification errors while debugging the bundle.

Hope it helps !! 🙂