Small enhancements in WebSocket example, refs #390

sarxos · sarxos · commit da713fe33d19 · 2015-09-12T14:01:41.000+02:00
diff --git a/webcam-capture-examples/webcam-capture-websockets/src/main/html/style.css b/webcam-capture-examples/webcam-capture-websockets/src/main/html/style.css
@@ -1,16 +1,21 @@
-
 .wrapper {
 	margin-left: auto;
 	margin-right: auto;
 	width: 1084px;
 	text-align: center;
 }
 
+.shadow {
+	border: 1px solid #f00;
+	transition: all .5s ease-in;
+}
+
 img {
 	margin-left: 8px;
 	margin-bottom: 8px;
 	width: 348px;
 	height: 198px;
 	box-shadow: 0 0 16px #444;
 	border: 1px solid #fff;
+	transition: all 1s ease-in;
 }
diff --git a/webcam-capture-examples/webcam-capture-websockets/src/main/html/ws.js b/webcam-capture-examples/webcam-capture-websockets/src/main/html/ws.js
@@ -29,9 +29,15 @@ $(document).ready(function() {
 				$webcams.append($img)
 			}
 		} else if (type === 'image') {
-			$("img[name='" + data.webcam + "']")
+			var $img = $("img[name='" + data.webcam + "']")
 				.attr("src", "data:image/jpeg;base64," + data.image)
+				.addClass('shadow')
 				.trigger("change");
+			setTimeout(function() {
+				$img
+					.removeClass('shadow')
+					.trigger("change");
+			}, 1000);
 		}
 	};
 
diff --git a/webcam-capture-examples/webcam-capture-websockets/src/main/java/WebcamCache.java b/webcam-capture-examples/webcam-capture-websockets/src/main/java/WebcamCache.java
@@ -4,6 +4,9 @@
 import java.util.List;
 import java.util.Map;
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 import com.github.sarxos.webcam.Webcam;
 import com.github.sarxos.webcam.WebcamEvent;
 import com.github.sarxos.webcam.WebcamListener;
@@ -12,6 +15,8 @@
 
 public class WebcamCache implements WebcamUpdater.DelayCalculator, WebcamListener {
 
+	private static final Logger LOG = LoggerFactory.getLogger(WebcamCache.class);
+
 	/**
 	 * How often images are updated on Dasding server.
 	 */
@@ -46,7 +51,13 @@ public long calculateDelay(long snapshotDuration, double deviceFps) {
 	}
 
 	public static BufferedImage getImage(String name) {
-		return CACHE.webcams.get(name).getImage();
+		Webcam webcam = CACHE.webcams.get(name);
+		try {
+			return webcam.getImage();
+		} catch (Exception e) {
+			LOG.error("Exception when getting image from webcam", e);
+		}
+		return null;
 	}
 
 	public static List<String> getWebcamNames() {
diff --git a/webcam-capture-examples/webcam-capture-websockets/src/main/java/WebcamWebSocketHandler.java b/webcam-capture-examples/webcam-capture-websockets/src/main/java/WebcamWebSocketHandler.java
@@ -103,10 +103,12 @@ public void newImage(Webcam webcam, BufferedImage image) {
 	}
 
 	private void send(String message) {
-		try {
-			session.getRemote().sendString(message);
-		} catch (IOException e) {
-			LOG.error("Exception when sending string", e);
+		if (session.isOpen()) {
+			try {
+				session.getRemote().sendStringByFuture(message);
+			} catch (Exception e) {
+				LOG.error("Exception when sending string", e);
+			}
 		}
 	}
 
diff --git a/webcam-capture-examples/webcam-capture-websockets/src/main/java/WebcamWebSocketsExample.java b/webcam-capture-examples/webcam-capture-websockets/src/main/java/WebcamWebSocketsExample.java
@@ -1,16 +1,17 @@
 import org.eclipse.jetty.server.Server;
 import org.eclipse.jetty.websocket.server.WebSocketHandler;
 import org.eclipse.jetty.websocket.servlet.WebSocketServletFactory;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import com.github.sarxos.webcam.Webcam;
 import com.github.sarxos.webcam.ds.ipcam.IpCamDriver;
 import com.github.sarxos.webcam.ds.ipcam.IpCamStorage;
 
 
 /**
- * This example demonstrates how webcam capture IP camera driver can be used
- * with conjunction with websockets to feed data to the web application
- * frontend.
+ * This example demonstrates how webcam capture IP camera driver can be used with conjunction with
+ * websockets to feed data to the web application frontend.
  * 
  * @author Bartosz Firyn (sarxos)
  */
@@ -20,10 +21,12 @@ public class WebcamWebSocketsExample {
 		Webcam.setDriver(new IpCamDriver(new IpCamStorage("src/main/resources/cameras.xml")));
 	}
 
+	private static final Logger LOG = LoggerFactory.getLogger(WebcamWebSocketsExample.class);
+
 	public static void main(String[] args) throws Exception {
 
 		for (String name : WebcamCache.getWebcamNames()) {
-			System.out.println("Will read webcam " + name);
+			LOG.info("Will read webcam {}", name);
 		}
 
 		Server server = new Server(8123);

Original file line number	Diff line number	Diff line change
`@@ -103,10 +103,12 @@ public void newImage(Webcam webcam, BufferedImage image) {`
`103`	`103`	`}`
`104`	`104`
`105`	`105`	`private void send(String message) {`
`106`		`- try {`
`107`		`- session.getRemote().sendString(message);`
`108`		`- } catch (IOException e) {`
`109`		`- LOG.error("Exception when sending string", e);`
	`106`	`+ if (session.isOpen()) {`
	`107`	`+ try {`
	`108`	`+ session.getRemote().sendStringByFuture(message);`
	`109`	`+ } catch (Exception e) {`
	`110`	`+ LOG.error("Exception when sending string", e);`
	`111`	`+ }`
`110`	`112`	`}`
`111`	`113`	`}`
`112`	`114`