Add: WorkerManager implementation

src/main/scala/core/WorkerManager.scala

@@ -0,0 +1,78 @@
+package core
+
+import com.alibaba.fastjson.JSON
+import com.typesafe.scalalogging.Logger
+import io.netty.channel.Channel
+import io.netty.channel.ChannelId
+import io.netty.handler.codec.http.websocketx.TextWebSocketFrame
+
+import scala.collection.mutable
+import utils.CheckInitialized
+
+object WorkerManager extends CheckInitialized(Logger(getClass)) {
+    private val threads = new mutable.Queue[Thread]()
+    private val log = Logger(getClass)
+
+    def init(threadNum: Int): Unit = {
+        if (initialized) { return }
+
+        synchronized {
+            if (initialized) { return }
+
+            for (i <- 0 until threadNum) {
+                threads.addOne(initThread(i))
+            }
+
+            log.info(s"${threadNum} worker threads are started.")
+            initialize()
+        }
+    }
+
+    private def initThread(id: Int): Thread = {
+        val thread = new Thread(new Task(id), s"worker-${id}")
+        QueueManager.get(id).workers.addOne(thread)
+        thread.setDaemon(true)
+        thread.start()
+        thread
+    }
+}
+
+case class Task(id: Int) extends Runnable {
+    private val log = Logger(getClass)
+    private var _queue: Option[MessageQueue] = None
+
+    def queue: MessageQueue = _queue.get
+
+    override def run(): Unit = {
+        log.debug(s"worker thread of queue ${queue.name} is working")
+
+        var message = new String();
+        while (true) {
+            try {
+                message = queue.take()
+                val channelIds = BasicMap.queueConsumerMap.get(queue.name)
+
+                while (queue == null || channelIds.isEmpty) {
+                    try {
+                        Thread.sleep(Long.MaxValue)
+                        log.debug("No consumers, sleeping...")
+                    } catch {
+                        case e: Exception =>
+                            log.warn(e.getMessage)
+                    }
+                }
+
+                for (channelId <- channelIds) {
+                    BasicMap.clients
+                        .find(channelId)
+                        .writeAndFlush(
+                          new TextWebSocketFrame(JSON.toJSONString(message))
+                        )
+                }
+            } catch {
+                case e: Exception =>
+                    log.warn(e.getMessage)
+            }
+        }
+    }
+}