FileReader idiomatic refactor (eugenp#3936)

pivovarit · web-flow · commit 64e9b41aefba · 2018-04-11T12:20:33.000+02:00
diff --git a/core-kotlin/src/main/kotlin/com/baeldung/filesystem/FileReader.kt b/core-kotlin/src/main/kotlin/com/baeldung/filesystem/FileReader.kt
@@ -1,39 +1,20 @@
 package com.baeldung.filesystem
 
-import java.io.BufferedReader
 import java.io.File
-import java.io.InputStream
 
 class FileReader {
 
-    fun readFileLineByLineUsingForEachLine(fileName: String): List<String> {
-        val lineList = mutableListOf<String>()
-        File(fileName).forEachLine { line -> lineList.add(line) }
-        return lineList
-    }
+    fun readFileLineByLineUsingForEachLine(fileName: String) = File(fileName).forEachLine { println(it) }
 
-    fun readFileAsLinesUsingUseLines(fileName: String): List<String> {
-        val lineList = mutableListOf<String>()
-        File(fileName).useLines { lines -> lineList.addAll(lines) }
-        return lineList
-    }
+    fun readFileAsLinesUsingUseLines(fileName: String): List<String> = File(fileName)
+      .useLines { it.toList() }
 
-    fun readFileAsLinesUsingBufferedReader(fileName: String): List<String> {
-        val bufferedReader: BufferedReader = File(fileName).bufferedReader()
-        return bufferedReader.readLines()
-    }
+    fun readFileAsLinesUsingBufferedReader(fileName: String): List<String> = File(fileName).bufferedReader().readLines()
 
-    fun readFileAsLinesUsingReadLines(fileName: String): List<String> {
-        return File(fileName).readLines()
-    }
+    fun readFileAsLinesUsingReadLines(fileName: String): List<String> = File(fileName).readLines()
 
-    fun readFileAsTextUsingInputStream(fileName: String): String {
-        val inputStream: InputStream = File(fileName).inputStream()
-        return inputStream.readBytes().toString(Charsets.UTF_8)
-    }
-
-    fun readFileDirectlyAsText(fileName: String): String {
-        return File(fileName).readText(Charsets.UTF_8)
-    }
+    fun readFileAsTextUsingInputStream(fileName: String) =
+      File(fileName).inputStream().readBytes().toString(Charsets.UTF_8)
 
+    fun readFileDirectlyAsText(fileName: String): String = File(fileName).readText(Charsets.UTF_8)
 }
