Gradle: Could not determine java version from '11.0.2'

Question

I ran the following comment:

./gradlew app:installDebug

only to be met with the log:

FAILURE: Build failed with an exception.

* What went wrong:
Could not determine java version from '11.0.2'.

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.

* Get more help at https://help.gradle.org

My version of gradle is 5.1.1:

------------------------------------------------------------
Gradle 5.1.1
------------------------------------------------------------

Build time:   2019-01-10 23:05:02 UTC
Revision:     3c9abb645fb83932c44e8610642393ad62116807

Kotlin DSL:   1.1.1
Kotlin:       1.3.11
Groovy:       2.5.4
Ant:          Apache Ant(TM) version 1.9.13 compiled on July 10 2018
JVM:          11.0.2 (Oracle Corporation 11.0.2+9-LTS)
OS:           Mac OS X 10.13.6 x86_64

I'm not sure how to proceed (I tried upgrading/downgrading, but nothing has worked so far).

UPDATE: When I ran ./gradlew --version, I got the following:

FAILURE: Build failed with an exception.

* What went wrong:
Could not determine java version from '11.0.2'.

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.

* Get more help at https://help.gradle.org

My gradle-wrapper.properties contains:

distributionBase=GRADLE_USER_HOME
distributionPath=wrapper/dists
zipStoreBase=GRADLE_USER_HOME
zipStorePath=wrapper/dists
distributionUrl=https\://services.gradle.org/distributions/gradle-4.1-rc-1-all.zip

Answer 1

There are two different Gradle applications in your system.

1. the system-wide Gradle
   This application is invoked by gradle (arguments).

2. the gradle-wrapper
   The gradle-wrapper is specific to every project and can only be invoked inside the project's directory, using the command ./gradlew (arguments).

Your system-wide gradle version is 5.1.1 (as the OP explained in the comments, running the command gradle --version returned version 5.1.1).

However, the failure is the result of a call to the gradle-wrapper (./gradlew). Could you check your project's gradle wrapper version? To do that, execute ./gradlew --version inside your project's folder, in the directory where the gradlew and gradlew.bat files are.

Update 1:
As running ./gradlew --version failed, you can manually check your wrapper's version by opening the file:

(project's root folder)/gradle/wrapper/gradle-wrapper.properties

with a simple text editor. The "distributionUrl" inside should tell us what the wrapper's version is.

Update 2: As per the OP's updated question, the gradle-wrapper's version is 4.1RC1.
Gradle added support for JDK 11 in Gradle 5.0. Hence since 4.1RC does not support JDK 11 this is definitely a problem.

The obvious way, would be to update your project's gradle-wrapper to version 5.0. However, before updating, try running gradle app:installDebug. This will use your system-wide installed Gradle whose version is 5.1.1 and supports Java 11. See if this works. If it does, then your buildscript (file build.gradle) is not affected by any breaking changes between v.4.1RC1 and v.5.1.1 and you can then update your wrapper by executing from the command line inside your project's folder: gradle wrapper --gradle-version=5.1.1 [*].

If gradle app:installDebug fails to execute correctly, then maybe you need to upgrade your Gradle buildscript. For updating from v.4.1RC1 to 5.1.1, the Gradle project provides a guide (1, 2) with breaking changes and deprecated features between minor releases, so that you can update gradually to the latest version.

Alternatively, if for some reason you can't or don't want to upgrade your Gradle buildscript, you can always choose to downgrade your Java version to one that Gradle 4.1RC1 supports.

[*] As correctly pointed out in another answer by @lupchiazoem, use gradle wrapper --gradle-version=5.1.1 (and not ./gradlew as I had originally posted there by mistake). The reason is Gradle runs on Java. You can update your gradle-wrapper using any working Gradle distribution, either your system-wide installed Gradle or the gradle-wrapper itself. However, in this case your wrapper is not compatible with your installed Java version, so you do have to use the system-wide Gradle (aka gradle and not ./gradlew).