Scala example source code file (Platform.scala)

This example Scala source code file (Platform.scala) is included in my "Source Code Warehouse" project. The intent of this project is to help you more easily find Scala source code examples by using tags.

All credit for the original source code belongs to scala-lang.org; I'm just trying to make examples easier to find. (For my Scala work, see my Scala examples and tutorials.)

Scala tags/keywords

anyref, array, class, concurrentmodificationexception, eol, int, platform, stackoverflowerror, string, unit

The Platform.scala Scala example source code

/*                     __                                               *\
**     ________ ___   / /  ___     Scala API                            **
**    / __/ __// _ | / /  / _ |    (c) 2002-2013, LAMP/EPFL             **
**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
** /____/\___/_/ |_/____/_/ | |                                         **
**                          |/                                          **
\*                                                                      */

package scala
package compat

import java.lang.System

object Platform {

  /** Thrown when a stack overflow occurs because a method or function recurses too deeply.
    *
    * On the JVM, this is a type alias for `java.lang.StackOverflowError`, which itself extends `java.lang.Error`.
    * The same rules apply to catching a `java.lang.Error` as for Java, that it indicates a serious problem that a reasonable application should not try and catch.
    */
  type StackOverflowError = java.lang.StackOverflowError

  /** This is a type alias for `java.util.ConcurrentModificationException`,
    * which may be thrown by methods that detect an invalid modification of an object.
    * For example, many common collection types do not allow modifying a collection
    * while it is being iterated over.
    */
  type ConcurrentModificationException = java.util.ConcurrentModificationException

  /** Copies `length` elements of array `src` starting at position `srcPos` to the
    * array `dest` starting at position `destPos`. If `src`==`dest`, the copying will
    * behave as if the elements copied from `src` were first copied to a temporary
    * array before being copied back into the array at the destination positions.
    *
    * @param src     A non-null array as source for the copy.
    * @param srcPos  The starting index in the source array.
    * @param dest    A non-null array as destination for the copy.
    * @param destPos The starting index in the destination array.
    * @param length  The number of elements to be copied.
    * @throws java.lang.NullPointerException If either `src` or `dest` are `null`.
    * @throws java.lang.ArrayStoreException If either `src` or `dest` are not of type
    *                [java.lang.Array]; or if the element type of `src` is not
    *                compatible with that of `dest`.
    * @throws java.lang.IndexOutOfBoundsException If either srcPos` or `destPos` are
    *                outside of the bounds of their respective arrays; or if `length`
    *                is negative; or if there are less than `length` elements available
    *                after `srcPos` or `destPos` in `src` and `dest` respectively.
    */
  @inline
  def arraycopy(src: AnyRef, srcPos: Int, dest: AnyRef, destPos: Int, length: Int) {
    System.arraycopy(src, srcPos, dest, destPos, length)
  }

  /** Creates a new array of the specified type and given length.
   *
   *  Note that if `elemClass` is a subclass of [[scala.AnyVal]] then the returned value is an Array of the corresponding java primitive type.
   *  For example, the following code `scala.compat.Platform.createArray(classOf[Int], 4)` returns an array of the java primitive type `int`.
   *
   *  For a [[scala.AnyVal]] array, the values of the array are set to 0 for ''numeric value types'' ([[scala.Double]], [[scala.Float]], [[scala.Long]], [[scala.Int]], [[scala.Char]],
   *  [[scala.Short]], and [[scala.Byte]]), and `false` for [[scala.Boolean]]. Creation of an array of type [[scala.Unit]] is not possible.
   *
   *  For subclasses of [[scala.AnyRef]], the values of the array are set to `null`.
   *
   *  The caller must cast the returned value to the correct type.
   *
   *  @example {{{
   *  val a = scala.compat.Platform.createArray(classOf[Int], 4).asInstanceOf[Array[Int]] // returns Array[Int](0, 0, 0, 0)
   *  }}}
   *
   *  @param elemClass the `Class` object of the component type of the array
   *  @param length    the length of the new array.
   *  @return          an array of the given component type as an `AnyRef`.
   *  @throws `java.lang.NullPointerException` If `elemClass` is `null`.
   *  @throws `java.lang.IllegalArgumentException` if componentType is [[scala.Unit]] or `java.lang.Void.TYPE`
   *  @throws `java.lang.NegativeArraySizeException` if the specified length is negative
   */
  @inline
  def createArray(elemClass: Class[_], length: Int): AnyRef =
    java.lang.reflect.Array.newInstance(elemClass, length)

  /** Assigns the value of 0 to each element in the array.
    * @param arr     A non-null Array[Int].
    * @throws `java.lang.NullPointerException` If `arr` is `null`.
    */
  @inline
  def arrayclear(arr: Array[Int]) { java.util.Arrays.fill(arr, 0) }

  /** Returns the `Class` object associated with the class or interface with the given string name using the current `ClassLoader`.
   *  On the JVM, invoking this method is equivalent to: `java.lang.Class.forName(name)`
   *
   *  For more information, please see the Java documentation for [[java.lang.Class]].
   *
   * @param    name the fully qualified name of the desired class.
   * @return   the `Class` object for the class with the specified name.
   * @throws `java.lang.LinkageError` if the linkage fails
   * @throws `java.lang.ExceptionInInitializerError` if the initialization provoked by this method fails
   * @throws `java.lang.ClassNotFoundException` if the class cannot be located
   *  @example {{{
   *  val a = scala.compat.Platform.getClassForName("java.lang.Integer")  // returns the Class[_] for java.lang.Integer
   *  }}}
   */
  @inline
  def getClassForName(name: String): Class[_] = java.lang.Class.forName(name)

  /** The default line separator.
   *
   * On the JVM, this is equivalent to calling the method:
   * `System.getProperty("line.separator")`
   * with a default value of "\n".
   */
  val EOL = scala.util.Properties.lineSeparator

  /** The current time in milliseconds. The time is counted since 1 January 1970
    * UTC.
    *
    * Note that the operating system timer used to obtain this value may be less
    * precise than a millisecond.
    */
  @inline
  def currentTime: Long = System.currentTimeMillis()

  /** Runs the garbage collector.
   *
   * This is a request that the underlying JVM runs the garbage collector.
   * The results of this call depends heavily on the JVM used.
   * The underlying JVM is free to ignore this request.
   */
  @inline
  def collectGarbage(): Unit = System.gc()

  /** The name of the default character set encoding as a string */
  @inline
  def defaultCharsetName: String = java.nio.charset.Charset.defaultCharset.name
}