Use multiple JDKs for Gradle with common modified cacerts

You already use your project with another JDK than the one embedded by Android Studio and have to have some JDK versions in parallel. Thats no big deal.

Trouble starts if you have to use custom certificates to communicate with your own server for e.g. downloading dependencies.

You have to patch those custom certificates to the JDKs cacerts. Each JDK installation contains its own cacerts. So you need to patch it every time you install a new JDK or update an existing one. Even worse if you use the Android Studio embedded JDK - if you patch that cacerts, your next update to Android Studio will fail.

However, if you have failed to patch the cacerts, you will get an error when you build your project with the new JDK and try to download dependencies from your server that require a custom certificate.

So to avoid having to patch every cacerts for every JDK version, it would be nice to have a common custom cacerts and use it regardless of the JDK version used.

You can achieve this by running gradle with the javax.net.ssl.trustStore parameter as follows:

gradle build -Djavax.net.ssl.trustStore=/PATH/TO/custom_cacerts

Note: The path to your custom_cacerts must be an absolute path. For example, you cannot use ~/custom_cacerts or $HOME/custom_cacerts.

Even better, you can set this parameter as the default for each Gradle execution by specifying it in your gradle.properties file. This way you don’t have to pass it along with the gradle command every time, and Android Studio uses this parameter as default as well.

Add the following line to the gradle.properties in your gradle user home ~/.gradle/gradle.properties:

systemProp.javax.net.ssl.trustStore=/PATH/TO/custom_cacerts

Info: You can configure Gradles Java process by providing parameters in the gradle.properties. The gradle.properties in your gradle user home can be used for global settings that will be used in every project. It will override those settings you may share with a gradle.properties file in your project folder.

For more details, see the Gradle properties documentation.