Scala 2.10 : Install2021/04/12 |
|
Install Scala 2.10.
|
|
| [1] | Confirm the current enabled version of Scala and Install it. |
|
[root@dlp ~]# dnf module list scala CentOS Stream 8 - AppStream Name Stream Profiles Summary scala 2.10 [d] common [d] A hybrid functional/object-oriented language for the JVM Hint: [d]efault, [e]nabled, [x]disabled, [i]nstalled[root@dlp ~]# scala -version Scala code runner version 2.10.6 -- Copyright 2002-2013, LAMP/EPFL |
| [2] | Run Scala REPL (Read Eval Print Loop) which is the interactive shell to Test Scala. |
|
[root@dlp ~]# scala Welcome to Scala version 2.10.6 (OpenJDK 64-Bit Server VM, Java 1.8.0_282). Type in expressions to have them evaluated. Type :help for more information. # print words scala> println("Hello Scala World") Hello Scala World # set constants scala> val msg:String = "Hello Scala World" msg: String = Hello Scala World scala> println(msg) Hello Scala World # exit scala> sys.exit |
| [3] | Create a sample program to Test Scala. |
|
[root@dlp ~]#
vi readfile.scala
import java.io.File
import java.io.FileReader
import java.io.BufferedReader
object readfile {
def main(args: Array[String]) {
val reader = new BufferedReader(new FileReader(new File("/etc/passwd")))
try {
var line : String = null
while ({ line = reader.readLine; line != null }) {
println(line)
}
} finally {
reader.close
}
}
}
# run as a script [root@dlp ~]# scala readfile.scala root:x:0:0:root:/root:/bin/bash bin:x:1:1:bin:/bin:/sbin/nologin daemon:x:2:2:daemon:/sbin:/sbin/nologin adm:x:3:4:adm:/var/adm:/sbin/nologin lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin ..... ..... # compile and run [root@dlp ~]# scalac readfile.scala [root@dlp ~]# scala readfile root:x:0:0:root:/root:/bin/bash bin:x:1:1:bin:/bin:/sbin/nologin daemon:x:2:2:daemon:/sbin:/sbin/nologin adm:x:3:4:adm:/var/adm:/sbin/nologin lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin sync:x:5:0:sync:/sbin:/bin/sync shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown ..... ..... |