Install/first-run fails on Java 9 with ClassCastException

[kirked]

I realise this is premature, but the release of Java 9 fast approaches...

I downloaded boot.sh on current Linux Mint, then ran this:

$ boot repl
Downloading https://github.com/boot-clj/boot/releases/download/2.6.0/boot.jar...
Exception in thread "main" java.lang.ClassCastException: jdk.internal.loader.ClassLoaders$AppClassLoader (in module: java.base) cannot be cast to java.net.URLClassLoader (in module: java.base)
	at Boot.loadJar(Boot.java:228)
	at Boot.main(Boot.java:254)
doug@twist ~/code/dashboard $ java -version
openjdk version "9-internal"
OpenJDK Runtime Environment (build 9-internal+0-2016-04-14-195246.buildd.src)
OpenJDK 64-Bit Server VM (build 9-internal+0-2016-04-14-195246.buildd.src, mixed mode)

[tobias]

This is caused by the app classloader being replaced in Java 9 - see tobias/clojure-java-9#3

[tobias]

This should be fixed by #539 and boot-clj/boot-bin#4.

[ghadishayban]

I tested this with JDK 7, 8, & 9 and it worked properly.

[laseray]

This is not fixed for me. Boot still fails to run under Java 9 (on Linux Mint 18.3) with latest snapshot. Gives the same Classloader error.

#http://boot-clj.com
#Fri Jan 26 15:26:16 EST 2018
BOOT_CLOJURE_NAME=org.clojure/clojure
BOOT_COLOR=yes
BOOT_VERSION=2.8.0-SNAPSHOT
BOOT_CLOJURE_VERSION=1.9.0

java -version
java version "9.0.4"
Java(TM) SE Runtime Environment (build 9.0.4+11)
Java HotSpot(TM) 64-Bit Server VM (build 9.0.4+11, mixed mode)

[prakashksinha]

hive 2.3.1 on jdk 9 not working. any clue?

[alexander-yakushev]

@laseray @prakashksinha Make sure you re-download the Boot binary file (boot.sh or boot.exe, see here https://github.com/boot-clj/boot#install)

[Bost]

I've got the same problem under java 1.10:

$ java -version
openjdk version "10.0.2" 2018-07-17
OpenJDK Runtime Environment (build 10.0.2+13-Ubuntu-1ubuntu0.18.04.4)
OpenJDK 64-Bit Server VM (build 10.0.2+13-Ubuntu-1ubuntu0.18.04.4, mixed mode)
$ boot -v
Exception in thread "main" java.lang.ClassCastException: java.base/jdk.internal.loader.ClassLoaders$AppClassLoader cannot be cast to java.base/java.net.URLClassLoader
	at Boot.loadJar(Boot.java:228)
	at Boot.main(Boot.java:254)

Edit: fixed by reinstalling according to https://github.com/boot-clj/boot#install

[alexander-yakushev]

@Bost are you using the latest Boot binary?

[Bost]

@alexander-yakushev That was the problem :) You may consider closing this issue. Thanx.