akka.util.Helpers.scala Maven / Gradle / Ivy
/**
* Copyright (C) 2009-2014 Typesafe Inc.
*/
package akka.util
import java.util.Comparator
import scala.annotation.tailrec
import java.util.regex.Pattern
import com.typesafe.config.Config
import scala.concurrent.duration.FiniteDuration
import scala.concurrent.duration.Duration
import java.util.concurrent.TimeUnit
import java.util.Locale
object Helpers {
val isWindows: Boolean = System.getProperty("os.name", "").toLowerCase(Locale.ROOT).indexOf("win") >= 0
def makePattern(s: String): Pattern = Pattern.compile("^\\Q" + s.replace("?", "\\E.\\Q").replace("*", "\\E.*\\Q") + "\\E$")
def compareIdentityHash(a: AnyRef, b: AnyRef): Int = {
/*
* make sure that there is no overflow or underflow in comparisons, so
* that the ordering is actually consistent and you cannot have a
* sequence which cyclically is monotone without end.
*/
val diff = ((System.identityHashCode(a) & 0xffffffffL) - (System.identityHashCode(b) & 0xffffffffL))
if (diff > 0) 1 else if (diff < 0) -1 else 0
}
/**
* Create a comparator which will efficiently use `System.identityHashCode`,
* unless that happens to be the same for two non-equals objects, in which
* case the supplied “real” comparator is used; the comparator must be
* consistent with equals, otherwise it would not be an enhancement over
* the identityHashCode.
*/
def identityHashComparator[T <: AnyRef](comp: Comparator[T]): Comparator[T] = new Comparator[T] {
def compare(a: T, b: T): Int = compareIdentityHash(a, b) match {
case 0 if a != b ⇒ comp.compare(a, b)
case x ⇒ x
}
}
/**
* Converts a "currentTimeMillis"-obtained timestamp accordingly:
* {{{
* "$hours%02d:$minutes%02d:$seconds%02d.$ms%03dUTC"
* }}}
*
* @param timestamp a "currentTimeMillis"-obtained timestamp
* @return the formatted timestamp
*/
def currentTimeMillisToUTCString(timestamp: Long): String = {
val timeOfDay = timestamp % 86400000L
val hours = timeOfDay / 3600000L
val minutes = timeOfDay / 60000L % 60
val seconds = timeOfDay / 1000L % 60
val ms = timeOfDay % 1000
f"$hours%02d:$minutes%02d:$seconds%02d.$ms%03dUTC"
}
final val base64chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789+~"
@tailrec
def base64(l: Long, sb: java.lang.StringBuilder = new java.lang.StringBuilder("$")): String = {
sb append base64chars.charAt(l.toInt & 63)
val next = l >>> 6
if (next == 0) sb.toString
else base64(next, sb)
}
/**
* Implicit class providing `requiring` methods. This class is based on
* `Predef.ensuring` in the Scala standard library. The difference is that
* this class's methods throw `IllegalArgumentException`s rather than
* `AssertionError`s.
*
* An example adapted from `Predef`'s documentation:
* {{{
* import akka.util.Helpers.Requiring
*
* def addNaturals(nats: List[Int]): Int = {
* require(nats forall (_ >= 0), "List contains negative numbers")
* nats.foldLeft(0)(_ + _)
* } requiring(_ >= 0)
* }}}
*
* @param value The value to check.
*/
@inline final implicit class Requiring[A](val value: A) extends AnyVal {
/**
* Check that a condition is true. If true, return `value`, otherwise throw
* an `IllegalArgumentException` with the given message.
*
* @param cond The condition to check.
* @param msg The message to report if the condition isn't met.
*/
@inline def requiring(cond: Boolean, msg: ⇒ Any): A = {
require(cond, msg)
value
}
/**
* Check that a condition is true for the `value`. If true, return `value`,
* otherwise throw an `IllegalArgumentException` with the given message.
*
* @param cond The function used to check the `value`.
* @param msg The message to report if the condition isn't met.
*/
@inline def requiring(cond: A ⇒ Boolean, msg: ⇒ Any): A = {
require(cond(value), msg)
value
}
}
/**
* INTERNAL API
*/
private[akka] final implicit class ConfigOps(val config: Config) extends AnyVal {
def getMillisDuration(path: String): FiniteDuration = getDuration(path, TimeUnit.MILLISECONDS)
def getNanosDuration(path: String): FiniteDuration = getDuration(path, TimeUnit.NANOSECONDS)
private def getDuration(path: String, unit: TimeUnit): FiniteDuration =
Duration(config.getDuration(path, unit), unit)
}
}