Tried to install Spark on my brand new MacAirbook running Tahoe 26.3. The first error message was that I needed to install Java 8 which I duly did. Now I try to install Spark the error message reads “JRE Directory not available. Could not unpack jar files. Please move the installation to a writable directory”. Is there a fix?
Looks like you downloaded a version without a bundled JRE i.e. spark_3_0_2-with-jre.dmg .
But I would recommend you to try the Nightly build instead spark_3_1_0-20260406-with-jre.dmg. In a few weeks it will be released as a next version. It contains a Java version upgrade and many other improvements.