#KT-3533 Fixed - not to null in encoding name parameter in String, Bytes, and File.

libraries/stdlib/src/kotlin/ArraysJVM.kt

@@ -104,12 +104,7 @@ public inline val ByteArray.inputStream : ByteArrayInputStream
 
 public inline fun ByteArray.inputStream(offset: Int, length: Int) : ByteArrayInputStream = ByteArrayInputStream(this, offset, length)
 
-public inline fun ByteArray.toString(encoding: String?): String {
-    if (encoding != null) {
-        return String(this, encoding)
-    } else {
-        return String(this)
-    }
-}
+public inline fun ByteArray.toString(encoding: String): String = String(this, encoding)
+public inline fun ByteArray.toString(): String = String(this)
 
 public inline fun ByteArray.toString(encoding: Charset) : String = String(this, encoding)

libraries/stdlib/src/kotlin/StringsJVM.kt

@@ -146,13 +146,8 @@ public inline fun CharSequence.toString() : String? = (this as java.lang.CharSeq
 public inline fun CharSequence.length() : Int = (this as java.lang.CharSequence).length()
 
 
-public inline fun String.toByteArray(encoding: String?=null):ByteArray {
-    if(encoding==null) {
-        return (this as java.lang.String).getBytes()
-    } else {
-        return (this as java.lang.String).getBytes(encoding)
-    }
-}
+public inline fun String.toByteArray():ByteArray = (this as java.lang.String).getBytes()
+public inline fun String.toByteArray(encoding: String):ByteArray = (this as java.lang.String).getBytes(encoding)
 public inline fun String.toByteArray(encoding: java.nio.charset.Charset):ByteArray =  (this as java.lang.String).getBytes(encoding)
 
 public inline fun String.toBoolean() : Boolean = java.lang.Boolean.parseBoolean(this)

libraries/stdlib/src/kotlin/io/Files.kt

@@ -110,33 +110,41 @@ public fun File.appendBytes(data: ByteArray): Unit {
 }
 
 /**
- * Reads the entire content of the file as a String using the optional
- * character encoding.  The default platform encoding is used if the character
- * encoding is not specified or null.
+ * Reads the entire content of the file as a String using the a character encoding.
  *
  * This method is not recommended on huge files.
  */
-public fun File.readText(encoding:String? = null) : String = readBytes().toString(encoding)
+public fun File.readText(encoding:String) : String = readBytes().toString(encoding)
 
 /**
- * Reads the entire content of the file as a String using the
+ * Reads the entire content of the file as a String using the default platform
  * character encoding.
  *
  * This method is not recommended on huge files.
  */
+public fun File.readText() : String = readBytes().toString()
+
+/**
+ * Reads the entire content of the file as a String using a character encoding.
+ *
+ * This method is not recommended on huge files.
+ */
 public fun File.readText(encoding:Charset) : String = readBytes().toString(encoding)
 
 /**
- * Writes the text as the contents of the file using the optional
- * character encoding.  The default platform encoding is used if the character
- * encoding is not specified or null.
+ * Writes the text as the contents of the file using the a
+ * character encoding.
  */
-public fun File.writeText(text: String, encoding:String?=null): Unit { writeBytes(text.toByteArray(encoding)) }
+public fun File.writeText(text: String, encoding:String): Unit { writeBytes(text.toByteArray(encoding)) }
 
 /**
- * Writes the text as the contents of the file using the optional
- * character encoding.  The default platform encoding is used if the character
- * encoding is not specified or null.
+ * Writes the text as the contents of the file using the default platform
+ * character encoding.
+ */
+public fun File.writeText(text: String): Unit { writeBytes(text.toByteArray()) }
+
+/**
+ * Writes the text as the contents of the file using a character encoding.
  */
 public fun File.writeText(text: String, encoding:Charset): Unit { writeBytes(text.toByteArray(encoding)) }
 
@@ -148,14 +156,19 @@ public fun File.appendText(text: String, encoding: Charset): Unit {
 }
 
 /**
- * Appends text to the contents of the file using optional character encoding.
- * The default platform encoding is used if the character encoding is
- * not specified or null.
+ * Appends text to the contents of the file using a character encoding.
  */
-public fun File.appendText(text: String, encoding: String? = null): Unit {
+public fun File.appendText(text: String, encoding: String): Unit {
     appendBytes(text.toByteArray(encoding))
 }
 
+/**
+ * Appends text to the contents of the file using default platform character encoding.
+ */
+public fun File.appendText(text: String): Unit {
+    appendBytes(text.toByteArray())
+}
+
 /**
  * Copies this file to the given output file, returning the number of bytes copied
  */

libraries/stdlib/src/kotlin/io/JIO.kt

@@ -315,11 +315,18 @@ public fun Reader.copyTo(out: Writer, bufferSize: Int = defaultBufferSize): Long
 }
 
 /**
- * Reads the entire content of the URL as a String with an optional character set name
+ * Reads the entire content of the URL as a String with a character set name
  *
  * This method is not recommended on huge files.
  */
-public fun URL.readText(encoding: String? = null): String = readBytes().toString(encoding)
+public fun URL.readText(encoding: String): String = readBytes().toString(encoding)
+
+/**
+ * Reads the entire content of the URL as a String with default character set name
+ *
+ * This method is not recommended on huge files.
+ */
+public fun URL.readText(): String = readBytes().toString()
 
 /**
  * Reads the entire content of the URL as a String with the specified character encoding.