Configuring an integration server to use a specified Java Runtime Environment (JRE)

Configure an independent or node-managed integration server to use a specified version of the Java Runtime Environment (JRE).

Before you begin

Your installed version of IBM® App Connect Enterprise must be 12.0.10.0 or later to be able to use this function.

By default, the integration server uses Java 8, which is provided with IBM App Connect Enterprise. Java 11 is also supplied with IBM App Connect Enterprise and you can configure each of your integration servers to use either of the supplied versions. Before you proceed, check whether any limitations apply to the integration nodes in your deployed message flows and to the type of security that you configured. For more information, see Limitations for JRE versions in IBM App Connect Enterprise.

About this task

Some features in IBM App Connect Enterprise depend on classes that are available only in specific versions of the JRE. For example, the Change Data Capture node requires classes that are available in Java 11 but not in Java 8. You can configure each of your integration servers to use the version that supports the applications that are deployed to the integration server.

Procedure

Configure the integration server to use a specified version of the JRE by completing the following steps:

Stop the integration server by using one of the methods described in Stopping an integration server.
Optional: If you are running an independent integration server, you have the option of optimizing the integration server by running the ibmint optimize server command.
For example, to optimize an integration server with the work directory C:\myServerWorkDir:
```
ibmint optimize server --work-directory C:\myServerWorkDir
```
The ibmint optimize server command is a static analysis tool that scans all deployed resources in an integration server and generates the server.components.yaml file. Any IBM App Connect Enterprise components that are not represented in the deployed message flows are set to false. When you start the integration server, all components that are set to false in the server.components.yaml file are prevented from starting up, thus increasing startup speed and reducing memory load. For more information about the ibmint optimize server command, see ibmint optimize server command.
Specify which JRE to use for the runtime by running the ibmint specify jre command.
For example, to use Java 11 for a node-managed integration server:
```
ibmint specify jre --version 11 --integration-node nodeName --integration-server serverName
```
If you specify Java 11, you can go back to using Java 8, which IBM App Connect Enterprise uses by default, by running the command again and specifying the value 8 for the parameter --version. For example, to use Java 8 for the independent integration server with the work directory C:\myServerWorkDir:
```
ibmint specify jre --version 8 --work-directory C:\myServerWorkDir
```
The ibmint specify jre command extracts details from the specified JRE and creates the server.java.yaml file. The contents of the server.java.yaml file together with the contents of the server.components.yaml file provide the integration server with the information that it needs on startup.
If you specify a version of the JRE that IBM App Connect Enterprise does not support, an error message similar to the following example is displayed:
```
BIP15263E: 'ABC Edition' by 'XYZ Corporation'
version '1.1' is not an approved JRE for use with App Connect
Enterprise version '12.0.10.0’
```
If this message is displayed, run the ibmint specify jre command again, specifying a supported version of the JRE.
If you need to update the server.java.yaml file, re-create it by running the ibmint specify jre command. If you edit the server.java.yaml file manually, the resulting behavior of the message flows can be unpredictable.

For more information about the ibmint specify jre command, see ibmint specify jre command.
Optionally, if you want to build and compile Java projects, you can select the JRE version from a menu in the IBM App Connect Enterprise Toolkit. For more information, see Selecting the JRE version for compiling Java projects in the IBM App Connect Enterprise Toolkit.
Start the integration server by using one of the methods described in Starting an integration server.

What to do next

Verify that the process was successful by deploying and testing your applications on the newly configured integration server. For more information, see How do I deploy and test message flows?