Merge pull request #5 from Bhashit/add-byte-array-constructor

Add a byte array constructor
kolotaev · Jul 28, 2019 · 98c8809 · 98c8809
2 parents 5667d94 + 21ffc6a
commit 98c8809
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Showing 2 changed files with 76 additions and 51 deletions.
diff --git a/src/main/scala/com/github/kolotaev/ride/Id.scala b/src/main/scala/com/github/kolotaev/ride/Id.scala
@@ -24,50 +24,73 @@ object Id {
   def apply(): Id = new Id()
 
   def apply(str: String): Id = new Id(str)
-}
 
-@SerialVersionUID(100L)
-class Id extends Serializable with Ordered[Id] {
-  import Id._
+  def apply(ba: Array[Byte]): Id = new Id(Some(ba))
 
-  // Constructing id value:
-  private val value: Array[Byte] = Array.fill[Byte](BinaryLen)(0)
+  private def decode(s: String): Array[Byte] = {
+    val pattern = s"[$encodeTable]{20}".r
+    s match {
+      case pattern() =>
+      case _ => throw new IllegalArgumentException(s"Argument should be 20 chars of any in $encodeTable")
+    }
 
-  // put first 4 bytes from current timestamp
-  private val timestamp: Int = System.timestamp
-  value(0) = (timestamp >> 24).toByte
-  value(1) = (timestamp >> 16).toByte
-  value(2) = (timestamp >> 8).toByte
-  value(3) = timestamp.toByte
+    val src: Array[Byte] = s.getBytes(Charset.forName("ASCII"))
+    val target = Array.fill[Byte](BinaryLen)(0)
+    target(0) = (decodeTable(src(0)) << 3 | decodeTable(src(1)) >> 2).toByte
+    target(1) = (decodeTable(src(1)) << 6 | decodeTable(src(2)) << 1 | decodeTable(src(3)) >> 4).toByte
+    target(2) = (decodeTable(src(3)) << 4 | decodeTable(src(4)) >> 1).toByte
+    target(3) = (decodeTable(src(4)) << 7 | decodeTable(src(5)) << 2 | decodeTable(src(6)) >> 3).toByte
+    target(4) = (decodeTable(src(6)) << 5 | decodeTable(src(7))).toByte
+    target(5) = (decodeTable(src(8)) << 3 | decodeTable(src(9)) >> 2).toByte
+    target(6) = (decodeTable(src(9)) << 6 | decodeTable(src(10)) << 1 | decodeTable(src(11)) >> 4).toByte
+    target(7) = (decodeTable(src(11)) << 4 | decodeTable(src(12)) >> 1).toByte
+    target(8) = (decodeTable(src(12)) << 7 | decodeTable(src(13)) << 2 | decodeTable(src(14)) >> 3).toByte
+    target(9) = (decodeTable(src(14)) << 5 | decodeTable(src(15))).toByte
+    target(10) = (decodeTable(src(16)) << 3 | decodeTable(src(17)) >> 2).toByte
+    target(11) = (decodeTable(src(17)) << 6 | decodeTable(src(18)) << 1 | decodeTable(src(19)) >> 4).toByte
+    target
+  }
+}
 
-  // next 3 bytes are the machine ID taken from md5 hash of the hostname
-  value(4) = machineID(0)
-  value(5) = machineID(1)
-  value(6) = machineID(2)
+@SerialVersionUID(100L)
+class Id(bytes: Option[Array[Byte]] = None) extends Serializable with Ordered[Id] {
+  import Id._
 
-  // next 2 bytes are the current process ID
-  value(7) = (PID >> 8).toByte
-  value(8) = PID.toByte
+  bytes.find { _.length != BinaryLen }.foreach { _ =>
+    throw new IllegalArgumentException(s"Binary representation must have length $BinaryLen")
+  }
 
-  // next 3 bytes are from ID counter
-  private val i: Int = idCounter.incrementAndGet
-  value(9) = (i >> 16).toByte
-  value(10) = (i >> 8).toByte
-  value(11) = i.toByte
+  // Constructing id value:
+  private val value: Array[Byte] = bytes.getOrElse {
+    val ba = Array.fill[Byte](BinaryLen)(0)
+
+    // put first 4 bytes from current timestamp
+    val timestamp: Int = System.timestamp
+    ba(0) = (timestamp >> 24).toByte
+    ba(1) = (timestamp >> 16).toByte
+    ba(2) = (timestamp >> 8).toByte
+    ba(3) = timestamp.toByte
+
+    // next 3 bytes are the machine ID taken from md5 hash of the hostname
+    ba(4) = machineID(0)
+    ba(5) = machineID(1)
+    ba(6) = machineID(2)
+
+    // next 2 bytes are the current process ID
+    ba(7) = (PID >> 8).toByte
+    ba(8) = PID.toByte
+
+    // next 3 bytes are from ID counter
+    val i: Int = idCounter.incrementAndGet
+    ba(9) = (i >> 16).toByte
+    ba(10) = (i >> 8).toByte
+    ba(11) = i.toByte
+    ba
+  }
 
 
   def this(str: String) {
-    this
-    // Spare counter increment is not valid in case of constructing from string
-    idCounter.decrementAndGet
-
-    val pattern = s"[$encodeTable]{20}".r
-    str match {
-      case pattern() =>
-      case _ => throw new IllegalArgumentException(s"Argument should be 20 chars of any in $encodeTable")
-    }
-
-    decode(str)
+    this(Some(Id.decode(str)))
   }
 
   def time: LocalDateTime = {
@@ -115,22 +138,6 @@ class Id extends Serializable with Ordered[Id] {
     result
   }
 
-  private def decode(s: String): Unit = {
-    val src: Array[Byte] = s.getBytes(Charset.forName("ASCII"))
-    value(0) = (decodeTable(src(0)) << 3 | decodeTable(src(1)) >> 2).toByte
-    value(1) = (decodeTable(src(1)) << 6 | decodeTable(src(2)) << 1 | decodeTable(src(3)) >> 4).toByte
-    value(2) = (decodeTable(src(3)) << 4 | decodeTable(src(4)) >> 1).toByte
-    value(3) = (decodeTable(src(4)) << 7 | decodeTable(src(5)) << 2 | decodeTable(src(6)) >> 3).toByte
-    value(4) = (decodeTable(src(6)) << 5 | decodeTable(src(7))).toByte
-    value(5) = (decodeTable(src(8)) << 3 | decodeTable(src(9)) >> 2).toByte
-    value(6) = (decodeTable(src(9)) << 6 | decodeTable(src(10)) << 1 | decodeTable(src(11)) >> 4).toByte
-    value(7) = (decodeTable(src(11)) << 4 | decodeTable(src(12)) >> 1).toByte
-    value(8) = (decodeTable(src(12)) << 7 | decodeTable(src(13)) << 2 | decodeTable(src(14)) >> 3).toByte
-    value(9) = (decodeTable(src(14)) << 5 | decodeTable(src(15))).toByte
-    value(10) = (decodeTable(src(16)) << 3 | decodeTable(src(17)) >> 2).toByte
-    value(11) = (decodeTable(src(17)) << 6 | decodeTable(src(18)) << 1 | decodeTable(src(19)) >> 4).toByte
-  }
-
   private def v(i: Int): Int = {
     if (value(i) < 0) value(i) + 256 else value(i).toInt
   }

diff --git a/src/test/scala/com/github/kolotaev/ride/IdSpec.scala b/src/test/scala/com/github/kolotaev/ride/IdSpec.scala
@@ -85,6 +85,24 @@ class IdSpec extends FlatSpec with Matchers {
     diff should equal (1)
   }
 
+  "IDs" should "be constructed correctly value when constructed using a bytes-array representation" in {
+    val bytes = Array[Byte](90, 61, 13, 107, 88, -105, 98, 106, -53, -1, -1, -3)
+    val strId = "b8ugqqqoith6livvvvug"
+    val a = Id(bytes)
+    a.getBytes should be (bytes)
+    a.toString should be (strId)
+    a should be (Id(strId))
+  }
+
+  "IDs" should "not increment counter when constructed with byte array" in {
+    val a = Id()
+    Id(a.getBytes)
+    Id(a.getBytes)
+    val c = Id()
+    val diff = c.counter - a.counter
+    diff should equal (1)
+  }
+
   "ID" should "throw IllegalArgumentException if wrong base32 string is passed to constructor" in {
     val data = List(
       "",