2 * Copyright 2011-2012 GRNET S.A. All rights reserved.
4 * Redistribution and use in source and binary forms, with or
5 * without modification, are permitted provided that the following
8 * 1. Redistributions of source code must retain the above
9 * copyright notice, this list of conditions and the following
12 * 2. Redistributions in binary form must reproduce the above
13 * copyright notice, this list of conditions and the following
14 * disclaimer in the documentation and/or other materials
15 * provided with the distribution.
17 * THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS
18 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
20 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GRNET S.A OR
21 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
23 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
24 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
25 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
27 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGE.
30 * The views and conclusions contained in the software and
31 * documentation are those of the authors and should not be
32 * interpreted as representing official policies, either expressed
33 * or implied, of GRNET S.A.
36 package gr.grnet.aquarium
38 import com.ckkloverdos.maybe.{Failed, MaybeOption, Just, NoVal, Maybe}
39 import java.nio.charset.Charset
40 import java.io.{PrintWriter, StringWriter}
41 import annotation.tailrec
47 * @author Christos KK Loverdos <loverdos@gmail.com>.
50 final val UTF_8_Charset = Charset.forName("UTF-8")
52 def tryOption[A](f: => A): Option[A] = {
55 case _: Exception => None
59 def withCloseable[C <: { def close(): Unit}, A](c: C)(f: C => A): A = {
68 * Compute the class name excluding any leading packages.
70 * This is basically the name after the last dot.
72 def shortNameOfClass(theClass: Class[_]): String = {
73 val cname = theClass.getName
74 cname.substring(cname.lastIndexOf(".") + 1)
78 * For the class of the provided object, compute the class name excluding any leading packages.
80 * This is basically the name after the last dot.
82 * The `null` value is mapped to string `"null"`.
84 def shortClassNameOf(anyRef: AnyRef): String = {
91 shortNameOfClass(obj.getClass)
95 def safeToStringOrNull(obj: AnyRef): String = obj match {
97 case _ => obj.toString
100 def displayableObjectInfo(obj: AnyRef): String = {
101 "[%s] %s".format(obj.getClass, obj)
105 * This basically turns an [[scala.Option]] into a [[com.ckkloverdos.maybe.Maybe]] when asking a
106 * [[scala.collection.Map]] for a key.
108 * @param map The input map.
109 * @param key The key we are interested in.
110 * @tparam A The type of keys.
111 * @tparam B The type of values.
113 * @return A [[com.ckkloverdos.maybe.Just]] if a value was found, a
114 * [[com.ckkloverdos.maybe.NoVal]] if nothing was found and a
115 * [[com.ckkloverdos.maybe.Failed]] if some error happened.
118 def findFromMapAsMaybe[A, B <: AnyRef](map: scala.collection.Map[A, B], key: A): Maybe[B] = Maybe {
128 def findAndRemoveFromMap[A, B <: AnyRef](map: scala.collection.mutable.Map[A, B], key: A): Maybe[B] = Maybe {
138 // Dear scalac. Optimize this.
139 def nspaces(n: Int): String = {
140 ("" /: (1 to n)) ((string, _) => string + " ")
143 def rpad(s: String, size: Int) = {
144 s + nspaces((size - s.length()) max 0)
147 def maxStringSize[A](trav: Traversable[A]): Int = {
148 (0 /: trav)(_ max _.toString.length)
152 * Given a [[com.ckkloverdos.maybe.Maybe]] that is actually a [[com.ckkloverdos.maybe.Failed]], return the latter.
154 * Use this only when you are sure what the `maybe` contains, since the methods can break type safety.
160 def failedForSure[A](maybe: Maybe[A]): Failed = {
161 maybe.asInstanceOf[Failed]
165 * Given a [[com.ckkloverdos.maybe.Maybe]] that is actually a [[com.ckkloverdos.maybe.Just]], return the latter.
167 * Use this only when you are sure what the `maybe` contains, since the methods can break type safety.
173 def justForSure[A](maybe: Maybe[A]): Just[A] = {
174 maybe.asInstanceOf[Just[A]]
178 * Transform an array of bytes to a string, assuming UTF-8 encoding.
180 def makeString(bytes: Array[Byte]): String = {
181 new String(bytes, UTF_8_Charset)
185 * Transform a string to an array of bytes, following a UTF-8 decoding scheme.
187 def makeBytes(string: String): Array[Byte] = {
188 string.getBytes(UTF_8_Charset)
192 * Return the stack trace of the given [[java.lang.Throwable]] in the form of [[java.lang.String]].
197 def stringOfStackTrace(t: Throwable): String = {
198 val sw = new StringWriter()
199 val pw = new PrintWriter(sw)
201 t.printStackTrace(pw)
209 def chainOfCauses(t: Throwable): List[String] = {
210 import scala.collection.mutable.ListBuffer
212 def loop(t: Throwable, buffer: ListBuffer[String]): List[String] = {
218 buffer.append("%s(%s)".format(shortClassNameOf(t), t.getMessage))
219 loop(t.getCause, buffer)
223 loop(t, new ListBuffer[String])