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--- pp:scalalab1 [2022/04/30 09:29]
vbadoiu
+++ pp:scalalab1 [2022/05/07 17:26] (current)
mihai.calitescu fixed typo
@@ Line 5: / Line 5: @@
   * practice writing **tail-recursive** functions as an alternative to imperative **loops**
   * keep your code clean and well-structured.
+** Make sure you have done your [[pp:scala-environment | scala environment]] setup ready **
 ** Create a new Scala worksheet to write your solutions **
@@ Line 122: / Line 124: @@
 </code>
-===== II. Scala in practice =====
+===== III. Scala in practice =====
-.1 Interacting with the filesystem. Scala uses Java implementations for using most of the operating system's functionalities. In the snippet below, we see the usage of the Java File class.
+Objectives:
+  * See some very simple examples of real world Scala
-<code Scala>
+**3.1** Interacting with the filesystem. Scala uses Java implementations for using most of the operating system's functionalities. In the snippet below, we see the usage of the Java File class.
-def getListOfFiles(dir: String):List[File] = {
-    val d = new File(dir)
-    if (d.exists && d.isDirectory) {
-        d.listFiles.filter(_.isFile).toList
-    } else {
-        List[File]()
-    }
-}
-</code>
 <code Scala>
-scala> import java.io.File
 import java.io.File
+val someFile = new File("somefile.txt")
+val fileSize = someFile.length
 </code>
+For this exercise we will want to implement a function that receives two files and returns the file with the maximum size.
+**3.2** Starting from the snippet below which defines a main function (the entry point of a program) in Scala. we want to make a standalone program that prints the size of a file given as an argument.
 <code Scala>
-scala> val files = getListOfFiles("/tmp")
+object Main {
-files: List[java.io.File] = List(/tmp/foo.log, /tmp/Files.scala.swp)
+  def main(args: Array[String]): Unit = {
+    println("Hello, Scala developer!")
+    if (args.length == 0) {
+        println("No parameter :(")
+    } else {
+        val filename = args(0)
+    }
+ }
+}
 </code>