Skip to content

How to use the IBM WebSphere DynaCache to store and share data

Applies to

HCL Digital Experience 8.5 and higher

Introduction

IBM WebSphere DynaCache provides an in-memory caching service that stores objects, dynamic content, and data across application server cluster members. Caching frequently accessed data reduces backend database workload and improves application response times. This article describes how to use IBM WebSphere DynaCache to store and share data.

Instructions

To use IBM WebSphere DynaCache to store and share data, perform the following steps:

Disclaimer of warranties

The enclosed code is sample code created by HCL Corporation. This sample code is provided to you solely for the purpose of assisting you in the development of your applications. The code is provided "AS IS", without warranty of any kind. HCL shall not be liable for any damages arising out of your use of the sample code, even if they have been advised of the possibility of such damages.

  1. Log in to the IBM Integrated Solutions Console (WAS admin console)
  2. Navigate to Resources > Cache instances > Object cache instances.

  3. In the Scope dropdown list, select a scope.

    • All scopes: Displays cache instances defined across all scope levels.
    • Cell=dockerCell: Applies the cache instance across all nodes and servers within the cell.
    • Node=dockerNode: Applies the cache instance across all servers on the specified node.
    • Node=dockerNode, Server=WebSphere_Portal: Applies the cache instance only to the specific server (standalone scope).

  4. Select New....

  5. Enter a Name and a JNDI name. For example:

    • Name: SampleCache
    • JNDI Name: custom/cache/SampleCache

  6. Select Apply.

  7. Click Save at the top of the console messages.

  8. Restart the HCL DX server.

    Note

    If the new object cache does not display when monitoring DynaCaches after restarting, select Refresh Instances .

  9. Add the following code to the view.jsp file used by your portlet:

    <%@ page import="com.ibm.websphere.cache.DistributedObjectCache" %>
Context context = new InitialContext();
DistributedObjectCache myCache = (DistributedObjectCache)context.lookup("custom/cache/SampleCache");
myCache.put("SampleParm", "hello");
System.out.println("distributedMap Size: " + myCache.size(true));
System.out.println("SampleParm: " + myCache.get("SampleParm"));

  10. Render the portlet and verify that lines similar to the following appear in SystemOut.log:

    [Timestamp] 000001a5 SystemOut O distributedMap Size: 1
[Timestamp] 000001a5 SystemOut O SampleParm: hello