Why build sample petclinic using java 17, but deploy it in azure using java 8?

Question

I download and build the petclinic sample code using java 17, the build is successful and I can run the application on localhost:8080. However, when I follow the step to deploy it to azure cloud service, it requires to use java 8 ( or 1.8) , then I see error. How to fix the issue? can we deploy it using java 17? if so, what is the plug-in id?

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Answer 1

Set Azure runtime to Java 17

Use Maven plugin:

com.microsoft.azure:azure-webapp-maven-plugin

or

com.microsoft.azure:azure-spring-apps-maven-plugin

No need to downgrade. Just confirm your pom.xml targets Java 17

(<maven.compiler.source> and <maven.compiler.target> set to 17).

1: XML snippet to properly set Java 17 in Maven pom.xml

Use this inside your <project> block (usually inside <properties>):

<properties>
    <java.version>17</java.version>
    <maven.compiler.source>17</maven.compiler.source>
    <maven.compiler.target>17</maven.compiler.target>
</properties>

This tells Maven to compile your project using Java 17

Works automatically with standard Azure deployment plugins.

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Answer 2

Hi Charlie Zhang, 

Thank you for reaching out to Microsoft Q & A forum.  

Thank you to Ruach Nephesh for providing a good starting point. 

To clarify: there is no need to downgrade your project to Java 8. You can deploy the Petclinic application using Java 17 by following these steps: 

Ensure your pom.xml includes the correct Java version settings: 

<properties>
  <java.version>17</java.version>
  <maven.compiler.source>17</maven.compiler.source>
  <maven.compiler.target>17</maven.compiler.target>
</properties>

In the Azure Maven plugin configuration, update the runtime to use Java 17: 

<runtime>
  <os>linux</os>
  <javaVersion>Java 17</javaVersion>
</runtime>

It is also recommended to use a newer version of the Azure Maven plugin, such as 2.12.0 or later. 

The original sample used Java 8 for broader compatibility, but Azure App Service now fully supports Java 17.      

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