Initial commit

src/main/kotlin/filesystem/FSCreator.kt

@@ -0,0 +1,25 @@
+package filesystem
+
+import java.nio.file.Files
+import java.nio.file.Path
+
+class FSCreator {
+    fun create(entryToCreate: FSEntry, destination: String) {
+        val queue = ArrayDeque<Pair<FSEntry, Path>>()
+        queue.add(entryToCreate to Path.of(destination))
+
+        while (queue.isNotEmpty()) {
+            val (entry, dest) = queue.removeFirst()
+            val path = dest.resolve(entry.name)
+            try {
+                when (entry) {
+                    is FSFile -> Files.createFile(path)
+                    is FSFolder -> Files.createDirectory(path)
+                }
+            } catch (_: FileAlreadyExistsException) {} // Allow files/folders to already exist.
+            if (entry is FSFolder) {
+                queue.addAll(entry.entries.map { it to path })
+            }
+        }
+    }
+}

src/main/kotlin/filesystem/FSEntry.kt

@@ -0,0 +1,9 @@
+package filesystem
+
+// Note sealed allows for simpler logic in FSCreator by guaranteeing FSFile and FSFolder are the only possible FSEntries
+// (as we expect), and it also makes the class abstract as required.
+sealed class FSEntry(val name: String)
+
+class FSFile(name: String, val content: String): FSEntry(name)
+
+class FSFolder(name: String, val entries: List<FSEntry>): FSEntry(name)