Add java websocket support (#137)

* add decode example for mic

* some changes to README.md

* add java websocket srv

* change to readwav to static

* make some changes to code comments

* little change for readme.md

* fix bug about multiple threads

* made little modification

* add protocol in readme, removed static Queue and add lmConfig

---------

Co-authored-by: root <root@localhost.localdomain>

java-api-examples/src/websocketsrv/StreamThreadHandler.java

@@ -0,0 +1,67 @@
+/*
+ * // Copyright 2022-2023 by zhaoming
+ */
+// java StreamThreadHandler
+package websocketsrv;
+
+import com.k2fsa.sherpa.onnx.OnlineStream;
+import java.nio.*;
+import java.util.*;
+import java.util.concurrent.*;
+import java.util.concurrent.LinkedBlockingQueue;
+import org.java_websocket.WebSocket;
+// thread for processing stream
+
+public class StreamThreadHandler extends Thread {
+  //  Queue between io network io thread pool and stream thread pool, use websocket as the key
+  private LinkedBlockingQueue<WebSocket> streamQueue;
+  //  Queue waiting for deocdeing, use websocket as the key
+  private LinkedBlockingQueue<WebSocket> decoderQueue;
+  // mapping between websocket connection and connection data
+  private ConcurrentHashMap<WebSocket, ConnectionData> connMap;
+
+  public StreamThreadHandler(
+      LinkedBlockingQueue<WebSocket> streamQueue,
+      LinkedBlockingQueue<WebSocket> decoderQueue,
+      ConcurrentHashMap<WebSocket, ConnectionData> connMap) {
+    this.streamQueue = streamQueue;
+    this.decoderQueue = decoderQueue;
+    this.connMap = connMap;
+  }
+
+  public void run() {
+    while (true) {
+      try {
+        // fetch one websocket from queue
+        WebSocket conn = (WebSocket) this.streamQueue.take();
+        // get the connection data according to websocket
+        ConnectionData connData = connMap.get(conn);
+        OnlineStream stream = connData.getStream();
+
+        // handle received binary data
+        if (!connData.getQueueSamples().isEmpty()) {
+          // loop to put all received binary data to stream
+          while (!connData.getQueueSamples().isEmpty()) {
+
+            float[] samples = connData.getQueueSamples().poll();
+
+            stream.acceptWaveform(samples);
+          }
+          //  if data is finished
+          if (connData.getEof() == true) {
+
+            stream.inputFinished();
+          }
+          // add this websocket to decoder Queue if not in the Queue
+          if (!decoderQueue.contains(conn)) {
+
+            decoderQueue.put(conn);
+          }
+        }
+
+      } catch (Exception e) {
+        e.printStackTrace();
+      }
+    }
+  }
+}