Run the WebLogic & Coherence Multitenant Examples


As part of the WebLogic 12.2.1 release a new new feature called “WebLogic Server Multitenant” has been introduced.  I’ve taken a couple of paragraphs from the Oracle WebLogic Server Documentation as it explains it nicely.

Multitenancy in WebLogic Server provides a sharable infrastructure for use by multiple organizations. These organizations are a conceptual grouping of your own choosing, which you can think of as tenants. By allowing one domain to support multiple tenants, WebLogic Server MT improves density and achieves a more efficient use of resources while eliminating the hurdles typically present when trying to share multiple applications: runtime cross-application impact, security differences, data co-mingling, and administrative challenges.

WebLogic Server MT provides resource isolation within a domain partition, an administrative and runtime slice of a WebLogic domain that is dedicated to running application instances and related resources for a tenant. Domain partitions achieve greater density by allowing application instances and related resources to share the domain, WebLogic Server itself, the Java virtual machine, and the operating system while isolating tenant-specific application data, configuration, and runtime traffic.

Coherence, when used in conjunction with WebLogic Server is fully supported in a multitenant environment.  When you deploy GARs (Grid Archives) and applications using Coherence, the services started within the applications are isolated by domain partition allowing multiple tenants to run the same Coherence application, but have private data and services.

Coherence & WebLogic Server Multitenant Example

When we released Coherence and WebLogic 12.1.2 back in August 2013, I showed how to run the examples we shipped which demonstrate how to use the new “GAR” model. See here for the details.

The standard examples are still there but we have included an example with a fully fledged Coherence & WebLogic Server application in a multi tenant domain.

The rest of this post will walk you though, in varying levels of detail, how to install and run these examples.

STEP 1 – Download and install JDK and WebLogic Server Generic

Download the Generic installer from OTN as well as the supported JDK for your platform. At the time of writing this it is 1.8.0_51 or above.

After you have installed the JDK, go do the directory where you downloaded WebLogic Server. You should see a file named:

Unzip this file which will create a file called fmw_12.

Follow the installation instructions in my original post here. When you have completed the install, remembering to choose “Complete Install”,  return to this post as some of the directories have changed slightly in this version.

STEP 2- Viewing the Examples Home Page

Now thats you’ve installed the JDK and WebLogic Server (with Examples:) ), we will take a look at the examples home page.  In my case I installed WebLogic into the following directory:


Using your browser, open up the following file, (replacing the WebLogic Server home with yours)


The page should look similar to the following:


Examples Home Page

You can see the second example is the Multitenant example. If you click on the link you will see the instructions for running the example as shown below.


Multitenant instructions

The instructions are quite detailed and explain how the example works.I’ve included a summary of how to run/ build below.

STEP 3 – Building and Start the Multitenant Domain

To build the domain, open a command prompt and issue the file for your environment.

E.g. for Windows

cd \Oracle\Middleware\1221\wlserver\server\bin


cd /u01/Middleware/1221/wlserver/server/bin
. ./

Once you have set your environment, change to the following directory:


Once here, you can issue the following command to build the domain. You will be asked a few questions. Be sure to check your hostname is correct, otherwise the build may not succeed. You can just press enter to leave the ports as default.

ant deploy

The output should be similar to below:


ant deploy

At the end of the build, you will see instructions showing you how to run the sample applications and get the the WebLogic Server Admin Console.


Build complete

STEP 4 – Run The Applications

There are two demonstration applications deployed.

Contact Application
This application shows the same contact application we shipped with previous versions, deployed unchanged in a multi tenant environment. The data for each for the domain partitions (tenants) is totally isolated. You can go to either of the URLs below and see the different data:

In the example above we are using URL prefixes for convenience to determine the different domain partitions, company1 and company2, but in normal environments you could use Virtual Targets behind a load balancer and map them to and

Stores Application
The stores application shows an example of sharing data between domain partitions in multi tenant application.

The concept of a “shared cache” between domain partitions is not enabled out of the box for obvious reasons but the administrator can configure this if required.

You can also go to the Admin console (URL in the output about) to see how this configuration is setup. A few sample screens are shown below.


Domain Partition Setup



STEP 5 – Stopping the Domain

You can issue the following to stop the enter WebLogic Server domain:

    ant shutdownMultiTenant


“WebLogic Server Multitenant” is an exciting new feature and is a great way to achieve more density and better utilise your WebLogic Server environments and is fully supported by Coherence applications.

For more information on configuring Coherence in a multitenant environment see the WebLogic Server / Coherence Documentation.





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Oracle Coherence on Docker

Happy new year to all!

Its going to be a busy year and I’m planning on doing a number of posts early this year to go into more depth into new 12.2.1 features. Stay tuned for these.

In the meantime, one of our Coherence Engineers has just published a great post outlining how to run Coherence on Docker.   See for the full post.

JK covers building Coherence Docker images, networking considerations including Coherence*Extend, JMX management, Persistence and Federation.

Well worth a read.


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Running the Coherence 12.2.1 Persistence Examples

In this post I’ll show you how to get started with the new Coherence Persistence feature in 12.2.1 by working through the examples that ship with the product.

Firstly a quick overview of what Persistence is about.

Persistence Introduction

Persistence is a set of tools and technologies that manage the persistence and recovery of Coherence distributed caches. Cached data is persisted so that it can be quickly recovered after a catastrophic failure or after a cluster restart due to planned maintenance. Persistence and federated caching can be used together as required.

Persistence can operate in two modes:

  • On-Demand persistence mode – a cache is manually persisted and recovered upon request using the snapshot manager. The snapshot manager is exposed as an MBean interface that provides operations for creating, archiving, and recovering snapshots of a cache.
  • Active persistence mode – In this mode, cache contents are automatically persisted on all mutations and are automatically recovered on cluster/service startup. The snapshot manager can be used in active persistence mode to perform on-demand snapshots of a cache.

See the the Online Documentation or our Persistence YouTube Screencast for more information.


Follow the instructions in my post from last month on how to install Coherence with the examples.  Once you have done this, then continue on to run the Persistence examples.

Setting your Environment 

Now that you have completed the installation above you need to open a command prompt or terminal window and setup your environment with the following environment variables:

  • JAVA_HOME  – points to the directory you install the JDK
  • COHERENCE_HOME – points to the base directory you installed Coherence to

Note: If you are running Coherence or greater, you will not need to set the COHERENCE_HOME variable.

Open a terminal and change to the examples/java directory under your Coherence home.

E.g. for Windows: (assuming you installed into c:\Oracle\Middleware\1221)

SET JAVA_HOME=c:\jdk\jdk1.8.0_65
cd \Oracle\Middleware\1221\coherence\examples\java
set COHERENCE_HOME=%cd%\..\..

Or for *NIX / Mac (using bash)

SET JAVA_HOME=/u01/jdk1.8/
cd /u01/product/coherence1221/coherence/examples/java
export COHERENCE_HOME=`pwd`/../..

Note: You don’t need to set JAVA_HOME on Mac.

Next run the following to check you have everything setup correctly:

bin\build contacts
bin\build persistence

You should see something like the following:

building contacts from com/tangosol/examples/contacts ...
Please refer to readme.txt for instructions on how to run the contacts example

If you don’t, check that you have JAVA_HOME and COHERENCE_HOME set correctly.

Hint for Windows users: Once you have completed the above, just type start in a command window and press enter. This will open another window with the same environment set. Do this a couple of times as we will need a number of command prompts.

Running the Examples

There are a number of different examples you can run to get a feel for how persistence works. Take a look in the readme.txt and search for ‘Persistence example’. The examples you can run are:

  1. Basic snapshot operations – shows how to issue Persistence Operations from Java
  2. Display Persistence notifications – shows how to use JMX Notifications to subscribe and display Persistence operations
  3. Running Persistence operations in parallel
  4. Advanced example – There are also SFTP snapshot archiver advanced example. (Leave that until you understand the concepts)

The readme.txt explains the steps to run each example, but I have included the Basic Snapshot operations example below for convenience.

The basic example shows how to call snapshot operations from Java.
Persistence is configured to store data in the ‘persistence-data’ directory under java examples home. Refer to resource/persistence/tangosol-coherence-override.xml for details of the defined persistence-environment.

First, build the persistence example using the following:
(Only required once, Ignore if you already did this above)

bin\build contacts
bin\build persistence

Next, start one or more cache servers using in separate terminals using:

bin\run-cache-server persistence

Next, in a separate terminal run the persistence example using:

bin\run persistence

The example will run and output similar to the following will be displayed:

------BasicSnapshotOperations example begin------

------Initial data size is 0------

------create new snapshots------
      create new snapshot snapshot-empty
      snapshots = [snapshot-empty]

------Populated data size is 10000------
      create new snapshot snapshot-10000
      snapshots = [snapshot-10000, snapshot-empty]

------recover snapshot------
      cleared cache, size = 0
      Recover snapshot snapshot-10000 containing 10000 entries
      cache size is now 10000
      Recover snapshot snapshot-empty containing 0 entries
      cache size is now 0

------removing snapshots------
      snapshots = []

------BasicSnapshotOperations example completed------

You can inspect the code in src/com/tangosol/examples/persistence directory. The file is the initial class for all persistence examples.

You will also see messages on the run-cache-server terminal indicating that Persistence operations are underway.

Note: Don’t forget to run through the other examples!

Viewing Persistence Using JVisualVM Plugin

Its worth installing the JVisualVM Plugin and take a look at the Persistence tab as well as Caches tab while you are running the examples.  See my post in the new JVisualVM Plugin for 12.2.1 for more information.

This post goes into a bit more depth on the MBeans that are available for working with Persistence through JMX connections.


Persistence is a great new feature and the examples show you how to get started with it and some of the functionality available.

Take a look at the Online Documentation for Persistence and email me let me know if you are interested in a more in-depth guide to Persistence as i have a lab guide that I can share.




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New Features in Coherence 12.2.1 JVisualVM Plug-in

Along with Coherence 12.2.1, we introduced a new version of the JVisualVM Plug-in supporting major new Coherence functionality such as Persistence and Federation, as well as including small incremental improvements.


As per our release notes: “Coherence persistence is a set of tools and technologies that manage the persistence and recovery of Coherence distributed caches. Cached data is persisted so that it can be quickly recovered after a catastrophic failure or after a cluster restart due to planned maintenance.”

I’ll be doing an in-depth post on Persistence soon, but take a look at the Coherence Documentation for more information.

When you connect to a cluster that has either on-demand (the default), or active persistence enabled, you will see a new persistence tab displayed.

Persistence Tab

We can see we have one service, PartitionedCache, which has active Persistence. The majority of the columns in the table are used for active persistence and show usage and latency information as well as the number of snapshots saved as well as status information

Persistence Menu OptionAs is shown in the menu option to the right, you can right-click on a service and issue the Persistence operations listed. These operations call JMX operations via the PersistenceCoordinator MBean.

Note: A Snapshot is a consistent copy of an entire service and can be used to recover a service to a known state.  Snapshots can be archived to central locations as an entire set and can be validated for consistency.

We can also see graphs of active space used and information on additional latency that may have been incurred using active mode. All these statistics are available in raw form under the Service MBean.

Persistence operations generate standard JMX notifications and we have added support to easily display these in the plug-in on the “Notifications” tab. If I create and then recover a snapshot you can see the notifications being generated.



Again, from the release notes: “Federated caching replicates and synchronizes cache data across multiple geographically dispersed clusters. Cached data is replicated across clusters to provide redundancy, off-site backup, and multiple points of access for application users in different geographical locations.”

Its a really exciting new feature that simplifies cross-cluster replication greatly. I’ve run the Federation demo, which is part of the OOTB Examples explained in this post, and connected to ClusterA via JVisualVM.

For more information on Federation see the Coherence Documentation.

Federation Tab

You can see that Federation details such as bandwidth utilization other statistics are displayed for the participants (clusters) in the topology. Various operations can also be carried out against the participants such as starting, pausing and resuming replication as well as forcing a replication of all data.

See the MBean reference for more details on the underlying Federation MBeans.

Other Updates to the Plug-in

Minor UI Update
In the upcoming patch, you will see a minor update to the plugin UI to more correctly align it with the general JVisualVM plugins.

Report Node State
Report Node StateOn the Members Tab, you can issue a ‘Show Node State’, which will run a Thread Dump remotely for that node which can me used to help diagnose issues.

Display Near Cache Details
When selecting a cache which is a near-cache, then information on the “near” portion will be displayed in the plug-in.

Near Cache

Hope you enjoy using the plugin and feel free to provide feedback and suggestions on how you use it and we can improve it.

Just as a reminder, when you install Coherence via the installer, the plug-in is available at $COHERENCE_HOME/coherence/plugins/jvisualvm/coherence-jvisualvm.nbm.

For details on how to install the plugin-in see the Documentation.

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Coherence / WebLogic Server 12.2.1 Workshop now in Adelaide, Melbourne & Sydney

Just a quick update to let you know the Free Coherence/WebLogic Server 12.2.1 hands-on workshop will also be in the following Australia Cities on the dates below:

  • Adelaide – Tuesday 1st December
  • Melbourne – Wednesday 2nd December
  • Sydney – Thursday 3rd December

The workshop is primarily focused on Coherence but we will cover some WebLogic Server new features in general and as they relate to Coherence.

Please contact me at tim dot middleton at oracle dot com for registration details for any of the above cities.

The summary of the workshop is below.

Workshop Overview

Bringing, their own laptops, attendees will have hands-on experience with the latest release of Coherence 12.2.1 and WebLogic Server 12.2.1 by exploring various examples and hands-on demonstrations including:

  • Data access, data loading, Java8, Lambda, Streams, Generics, Security
  • Data operations including: querying, aggregating, listening and processing
  • Federated Caching for continuous available across sites
  • Cache Persistence for automated recovery and cluster snapshot creation
  • Accessing Coherence via REST though a AngularJS application
  • Integrating Coherence with WebLogic Server 12cR2 Multi-tenancy, Coherence Grid-Archives (GAR) and issuing Rolling redeploy
  • Using the Coherence JVisualVM Plug-in to monitor Coherence Development environments
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New Screencasts Showcasing Coherence 12.2.1 Features

We have just released a new set of screencasts showcasing the major new features in Coherence 12.2.1.  All the videos have been recorded by the Engineers that built the product and include some great insights into the rationale behind the features, how the features work and most of them include demonstrations.

You can go to the Oracle Coherence YouTube Channel for playlists, or you can checkout individual screencasts below:

These videos are well worth the time to get up to speed on new functionality.

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Exploring new Coherence 12.2.1 Features Through the OOTB Examples

With the release of Coherence 12.2.1 we have included many examples so you can get hands-on experience existing features as well as getting up to speed with new features such as support for Java8, Cache Persistence, Federation and Async processing API.

Download Coherence & Java 8

  1. Ensure you have downloaded and installed the latest Java8 SE Developers kit available from OTN
  2. Download the Coherence Standalone Install from OTN
  3. Unzip the downloaded file which will give you a jar called fmw_12.

Install Coherence

To install Coherence, follow the instructions in Section 2.2 of Installation Documentation. A shortened version of this is below. (Refer to the above link if you have any issues)

  1. Open up a command prompt or terminal and set JAVA_HOME environment variable to your installed Java 8 JDK. E.g. for Windows:
    SET JAVA_HOME=c:\jdk\jdk1.8.0_65
  2. Run java command with -jar option pointing to your downloaded fmw_12. E.g.
    %JAVA_HOME%\bin\java -jar c:\downloads\fmw_12.
  3. Click Next and Choose Auto-Updates option.
  4. Choose an installation location, e.g. c:\Oracle\Middleware\1221 and click Next.
  5. Ensure you select ‘Coherence with Examples’ option then carry on to complete the installation.

Navigate To the Examples Directory

Once the installation has completed you will find a coherence\examples directory under the installation directory you chose above. E.g. if you installation directory was c:\Oracle\Middleware\1221 then the examples directory will be c:\Oracle\Middleware\1221\coherence\examples.

Within this directory you will find the following directories java, cpp, dotnet and rest. In each of these directories refer to the readme.txt which includes explanations on how to run each example.  You can also refer to the online documentation as well.

I’ve included some highlights of the directories and the examples we ship within them:

  • rest – This directory contains a modern web application using using AngularJS and Bootstrap to showcase how to access Coherence via REST. This is the only example currently that uses maven to build and run.
  • java – Includes various Java examples including:
    • Java 8 support including Lambdas, Streams, Map Default methods
    • New NamedCache Async API
    • Federation
    • Cache Persistence
    • Events
    • Security

For more details on the above new features, see my Coherence 12.2.1 Overview post.

Keep your eyes out for a post on how to run the Coherence and WebLogic Server examples.


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