Steps to downgrade Java version for compatibility with SAP CPI

Introduction: –

            It is important to ensure that the external JAR file used in CPI Integrations is compatible with the version of Java supported by CPI. Updating the JAR file in Eclipse may result in the JAR version being automatically updated to the latest Java version (Java SE 17, which supports class file versions up to 61.0), which could cause compatibility issues with CPI (which supports Java SE 1.8 supports class file versions from 45.0 to 52.0.)

           To address this, it is possible to downgrade the Java version in Eclipse by following certain steps. However, it is crucial to ensure that the downgraded Java version is still supported by CPI and that there are no security or performance implications of downgrading the Java version.

Problem Statement: –

If an incorrect Java version is uploaded, CPI will generate an error. Therefore, it is essential to be aware of the Java class file version compatibility with the target Java environment (CPI) before compiling or deploying the code.

Resolution: –

•  Suppose there is an existing JAR file in an interface that needs to be modified.

Picture showing the working version of Jar in the integration

To modify the JAR file, the usual approach is to use Eclipse. Once the modifications have been made to the JAR file in Eclipse, it can be exported and imported into CPI. However, upon deploying the interface after importing the modified JAR file, an error occurs.

Interface failed after uploading the updated Jar File

Below is the error message from CPI

Error Message in CPI post deployment

To prevent compatibility issues with SAP CPI, it is important to ensure that the Java version used for editing the Jar file in Eclipse is aligned with the supported Java version.

To achieve this, before exporting the Jar file from Eclipse, follow the below steps to set the Java version to 1.8:

1. Right-click on the project, select “Build Path,” and then click on “Configure Build Path.”

2.Click on Classpath and then click on  Add Library.

3. Click on JRE System Library and then Next

4. To ensure compatibility with SAP CPI, select the appropriate execution environment by clicking on “Execution Environment” and choosing “JavaSE-1.8 (jre)” from the options. After making this selection, click “Finish” and then “Apply”.

5. Once the necessary changes have been made, export the updated Jar file. Finally, import the Jar file into SAP CPI and deploy the updated integration flow.

Conclusion: –

By following these steps, you can configure Eclipse to use the desired Java version for your project and ensure compatibility with the external JAR file.

Hope this blog helps. 😊