It seems as if my scala installation does not contain a rather fundamental package, scala.language:
scala> import language._
<console>:7: error: not found: value language
import language._
^
scala> import scala.language._
<console>:7: error: object language is not a member of package scala
import scala.language._
I've re-installed scala from my Linux repositores (I'm running LMDE 2 "Betsy"), yet I've had no luck. It is unclear to me how exactly I can just download the respective jar, place it somewhere in my system and have the import work.
Here are specs about my system and java/scala installation that might be of use:
jasonfil#hp ~ $ cat /etc/debian_version
8.1
jasonfil#hp ~ $ uname -r
3.16.0-4-amd64
jasonfil#hp ~ $ scala -version
Scala code runner version 2.9.2 -- Copyright 2002-2011, LAMP/EPFL
jasonfil#hp ~ $ java -version
java version "1.7.0_79"
OpenJDK Runtime Environment (IcedTea 2.5.6) (7u79-2.5.6-1~deb8u1)
OpenJDK 64-Bit Server VM (build 24.79-b02, mixed mode)
jasonfil#hp ~ $ echo $CLASSPATH
/home/jasonfil/AtomicScala/examples:/usr/share/java
Indeed, as #ymonad said, this appeared to be a question of trusting the language's source more than the Debian repo version. Marking this solved. Thanks.
Related
I'm trying to uninstall scala so I can redownload an older version for compatibility reasons. I thought I had done it but whenever I run scala, it still runs the latest version, the one I thought I had uninstalled. This is the code I've been running in my terminal, I'm on a macbook also, anymore info needed lmk, any help is much appreciated!
➜ ~ scala
Welcome to Scala 3.2.0 (18.0.2.1, Java Java HotSpot(TM) 64-Bit Server VM).
Type in expressions for evaluation. Or try :help.
scala> :q
➜ ~ brew list scala
Error: No such keg: /usr/local/Cellar/scala
➜ ~ brew uninstall scala
Error: No such keg: /usr/local/Cellar/scala
could someone suggest elegant way to upgrade javac in Debian to version 8 ?!
javac -version
javac 1.7.0_261
java -version
java version "1.8.0_251"
Java(TM) SE Runtime Environment (build 1.8.0_251-b08)
Java HotSpot(TM) 64-Bit Server VM (build 25.251-b08, mixed mode)
to those who needs elegant solution:
download JVM from oracle: http://java.sun.com/products/archive/
if you use Linux as I do, *.tar.gz file can be chosen (it has all related binaries)
in Debian or other Linux untar it with command "tar xvzf PACKAGENAME.tar.gz", as a result all folders and subfolders will be created in related new folder, e.g. jdk-8u251-linux-x64. Related version of javac is in "dk-8u251-linux-x64/bin/" subfolder
copy this all structure e.g. "jdk-8u251-linux-x64" e.g. to /home/user1
modify PATH variable to allow system find related new javac: PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/home/user1/jdk1.8.0_251/bin/
old javac can be renamed as a backup: mv /usr/bin/javac /usr/bin/javac_old
verification of the result:
javac -version
javac 1.8.0_251
Now javac on my system has the same version as java (as mentioned above, before they were quite different). In version 8 Java have several changes, e.g. some new ways how Time is handeling, which forced me to such changes.
Getting below error in Scala REPL
scala> :javap -p Add
java.lang.IllegalArgumentException: requirement failed
at scala.Predef$.require(Predef.scala:264)
at scala.tools.nsc.interpreter.JavapClass$JavapTool$.apply(JavapClass.scala:337)
at scala.tools.nsc.interpreter.JavapClass.tool$lzycompute(JavapClass.scala:37)
at scala.tools.nsc.interpreter.JavapClass.tool(JavapClass.scala:37)
at scala.tools.nsc.interpreter.JavapClass.apply(JavapClass.scala:49)
at scala.tools.nsc.interpreter.ILoop.javapCommand(ILoop.scala:332)
at scala.tools.nsc.interpreter.ILoop.$anonfun$standardCommands$6(ILoop.scala:187)
at scala.tools.nsc.interpreter.LoopCommands$LineCmd.apply(LoopCommands.scala:132)
at scala.tools.nsc.interpreter.LoopCommands.colonCommand(LoopCommands.scala:103)
at scala.tools.nsc.interpreter.LoopCommands.colonCommand$(LoopCommands.scala:101)
at scala.tools.nsc.interpreter.ILoop.colonCommand(ILoop.scala:44)
at scala.tools.nsc.interpreter.ILoop.command(ILoop.scala:696)
at scala.tools.nsc.interpreter.ILoop.processLine(ILoop.scala:416)
at scala.tools.nsc.interpreter.ILoop.loop(ILoop.scala:437)
at scala.tools.nsc.interpreter.ILoop.$anonfun$process$1(ILoop.scala:1012)
at scala.tools.nsc.interpreter.ILoop.process(ILoop.scala:909)
at scala.tools.nsc.MainGenericRunner.runTarget$1(MainGenericRunner.scala:75)
at scala.tools.nsc.MainGenericRunner.run$1(MainGenericRunner.scala:88)
at scala.tools.nsc.MainGenericRunner.process(MainGenericRunner.scala:99)
at scala.tools.nsc.MainGenericRunner$.main(MainGenericRunner.scala:104)
at scala.tools.nsc.MainGenericRunner.main(MainGenericRunner.scala)
That entry seems to have slain the compiler. Shall I replay
your session? I can re-run each line except the last one.
[y/n]
Abandoning crashed session.
Please share if anyone encountered this issue & able to resolve. Below is the versions information. Thanks in advance!
C:\Users\email>scala -version
Scala code runner version 2.12.2 -- Copyright 2002-2017, LAMP/EPFL and Lightbend, Inc.
C:\Users\email>java -version
java version "1.8.0_131"
Java(TM) SE Runtime Environment (build 1.8.0_131-b11)
Java HotSpot(TM) 64-Bit Server VM (build 25.131-b11, mixed mode)
As the answer said Why does installing Scala require additionally installing JDK?
Maybe you just installed Jre not JDK.
To solve the problem, install the corresponding version JDK.
:javap command within Scala REPL invoke the javap tool installed by JAVA SDK via java.util.spi.ToolProvider[ver2.13.1]. Jre don't include those JDK tools such as javap, jdb, jar.
On Ubuntu 16.04, I installed scala:
$ls ~/Binary/scala-2.11.8
bin doc lib man
$grep -A 2 SCALA ~/.bashrc
SCALA=~/Binary/scala-2.11.8
SBT=~/Binary/sbt
export PATH=$PATH:$SCALA/bin:$SBT/bin
With openjdk8 installed, scala fails when opening the REPL:
$javac -version
javac 1.8.0_91
$
$scala
Welcome to Scala 2.11.8 (OpenJDK 64-Bit Server VM, Java 9-internal).
Type in expressions for evaluation. Or try :help.
scala>
Failed to initialize compiler: object java.lang.Object in compiler mirror not found.
** Note that as of 2.8 scala does not assume use of the java classpath.
** For the old behavior pass -usejavacp to scala, or if using a Settings
** object programmatically, settings.usejavacp.value = true.
Failed to initialize compiler: object java.lang.Object in compiler mirror not found.
** Note that as of 2.8 scala does not assume use of the java classpath.
** For the old behavior pass -usejavacp to scala, or if using a Settings
** object programmatically, settings.usejavacp.value = true.
How can I resolve it?
Using the Java 8 version of OpenJDK resolved this issue for me.
sudo update-alternatives --config java
sudo update-alternatives --config javac
Java 8 is deprecated, so downgrading to is must NOT be an acceptable solution.
The correct solution is to upgrade your SBT to 0.13.17 or higher.
This issue appears to be with Java 9 and gets solved with Java 8.
If you have Java 8 and Java 9, and you would like to keep both, you can set your environment variable JAVA_HOME to the Java 8 path.
For example:
export JAVA_HOME=/Library/Java/JavaVirtualMachines/jdk1.8.0_161.jdk/Contents/Home
You will need to replace jdk1.8.0_161.jdk with whichever version of the JDK that you have.
You can find that version with:
ls /Library/Java/JavaVirtualMachines/
Once you set that environment variable, you can open a new terminal and run java -version to see if the version was set correctly.
EDIT:
It may be worth noting that I have a Mac even though this is a linux question.
Installing java version "1.8.0_144" resolved the issue for me. I had installed jdk 1.9 previously.
If you're using an older version of Scala that is not compatible with JDK greater than 8, update to a newer version that's compatible with JDK 11. JDK 11 is current the LTS.
Versions by minor version:
For 2.11.x this means 2.11.12 or later
For 2.12.x this means 2.12.10 or later
For 2.13.x this means 2.13.1 or later
As other answers mentioned, make sure you're also using a build tool that's compatible with JDK >8 (e.g. sbt greater than 0.13.17).
Installing Java 8 resolved this issue.
I downloaded java 8 and i extracted that to the following location : /usr/lib/jvm/jdk1.8.0_172
After doing this update the JAVA_HOME path to the same : /usr/lib/jvm/jdk1.8.0_172
This will resolve the issue.
Worked with this java version "1.8.0_144"
Uninstall java and apache-spark
install java, install apache-spark
I ran into the same issue. Uninstall Java 9
sudo rm -fr /Library/Java/JavaVirtualMachines/jdk-9.jdk/
sudo rm -fr /Library/Internet\ Plug-Ins/JavaAppletPlugin.plugin
sudo rm -fr /Library/PreferencePanes/JavaControlPanel.prefPane
Ref: https://gist.github.com/schnell18/bcb9833f725be22f6acd01f94b486392
Install Java 8.
Everything seems to good now.
Btw: this was for mac. Might be useful for you.
i had a zip of my jdk at the same location. Removing the zip did the trick for me.
Noob question incoming.
I just uninstalled scala 2.9.2 from my machine in doing:
sudo apt-get remove scala
While the command:
scala -version
outputs:
The program 'scala' is currently not installed. You can install it by typing: sudo apt-get install scala
My scala/sbt program still functions...
Why? I do not know.
I would like to install the latest version of scala which is the 2.11.7.
My questions are:
- How do I fully uninstall scala?
- How do I install scala 2.11.7? (In which directory uncompress the .tgz? What bindings?)
SBT is not scala
the command sbt usually is a wrapper script that launches sbt-launch.jar in [home]/.sbt/launchers. Where that wrapper script is installed to heavily depends on how you installed it.
SBT downloads its own scala version into a projects target path. It is totally local, so imo there is not reason to worry about installation relics.
Thus, if you want to use scala 2.11.7, just set scalaVersion := 2.11.7 in your build.sbt