Problem scenario
Presto will not run because of an error about the JVM.
You get a message like this:
"Java version has an unknown format: 15" (from "C" below)
"Presto requires an Oracle or OpenJDK JVM (found Ubuntu)" (associated with the Java version shown in B or D below)
"Presto requires an Oracle or OpenJDK JVM (found Private Build)" (associated with the Java version in E below)
"Presto requires an Oracle or OpenJDK JVM (found IcedTea)" (associated with the Java version shown in F below)
Solution
For detailed background information, here are six outputs of "java -version":
A.
openjdk version "1.8.0_265"
OpenJDK Runtime Environment (build 1.8.0_265-b01)
OpenJDK 64-Bit Server VM (build 25.265-b01, mixed mode)
B.
openjdk version "11.0.8" 2020-07-14
OpenJDK Runtime Environment (build 11.0.8+10-post-Ubuntu-0ubuntu120.04)
OpenJDK 64-Bit Server VM (build 11.0.8+10-post-Ubuntu-0ubuntu120.04, mixed mode, sharing)
C.
java version "15" 2020-09-15
Java(TM) SE Runtime Environment (build 15+36-1562)
Java HotSpot(TM) 64-Bit Server VM (build 15+36-1562, mixed mode, sharing)
D.
openjdk version "14.0.1" 2020-04-14
OpenJDK Runtime Environment (build 14.0.1+7-Ubuntu-1ubuntu1)
OpenJDK 64-Bit Server VM (build 14.0.1+7-Ubuntu-1ubuntu1, mixed mode, sharing)
E.
openjdk version "1.8.0_265"
OpenJDK Runtime Environment (build 1.8.0_265-8u265-b01-0ubuntu2~20.04-b01)
OpenJDK 64-Bit Server VM (build 25.265-b01, mixed mode)
F.
openjdk version "1.8.0_252"
OpenJDK Runtime Environment (IcedTea 3.16.0) (build 1.8.0_252-b09 suse-3.35.3-x86_64)
OpenJDK 64-Bit Server VM (build 25.252-b09, mixed mode)
The word "ubuntu" appears in three of the six. Some versions of Presto lend themselves, as of September 2020, to Python 2. We found issues with Java version 15, SUSE and Ubuntu/Debian packaged Javas. Be believe that the details of the "version" are taken from the binary Java file. We do not think they can be modified or faked easily.
We recommend using a Red Hat derivative of Linux for deploying Presto or a newer version of Presto (if you use Debian, Ubuntu or SUSE). As of late September 2020, there is a version 0.241 that seems quite stable and another version 0.3x that seems acceptable too.