jpospychala · November 6, 2012 13:27 · Nov 6, 2012
diff --git a/DetectNoResponse.java b/DetectNoResponse.java
@@ -0,0 +1,70 @@
+import java.util.Iterator;
+import java.util.Map;
+
+import org.eclipse.swt.widgets.Display;
+
+public class DetectNoResponse {
+
+	// timeout (msec) minimal time of no response to detect
+	protected long timeout = 1000;
+	protected long displayThreadResponse;
+	private boolean isRunning;
+
+	public void start() {
+		isRunning = true;
+		Thread t = new Thread(new Runnable() {
+			public void run() {
+				displayThreadResponse = System.currentTimeMillis();
+				while ((!Display.getDefault().isDisposed()) && isRunning) {
+					pingDisplayThread();
+					long now = System.currentTimeMillis();
+
+					try {
+						Thread.sleep(timeout);
+					} catch (InterruptedException e) {
+						// ignore
+					}
+
+					long responseTime = Math.abs(now - displayThreadResponse);
+					if (responseTime > timeout) {
+						System.err.println("No response for "+responseTime);
+						System.err.println(captureThreadDump());
+					}
+				}
+			}
+		});
+		t.start();
+	}
+
+	public static String captureThreadDump() {
+		// from http://henryranch.net/software/capturing-a-thread-dump-in-java/
+		Map allThreads = Thread.getAllStackTraces();
+		Iterator iterator = allThreads.keySet().iterator();
+		StringBuffer stringBuffer = new StringBuffer();
+		while (iterator.hasNext()) {
+			Thread key = (Thread) iterator.next();
+			StackTraceElement[] trace = (StackTraceElement[]) allThreads
+					.get(key);
+			stringBuffer.append(key + "\r\n");
+			for (int i = 0; i < trace.length; i++) {
+				stringBuffer.append(" " + trace[i] + "\r\n");
+			}
+			stringBuffer.append("");
+		}
+		return stringBuffer.toString();
+	}
+
+	protected void pingDisplayThread() {
+		Display.getDefault().asyncExec(new Runnable() {
+
+			public void run() {
+				displayThreadResponse = System.currentTimeMillis();
+			}
+		});
+	}
+
+	public void stop() {
+		isRunning = false;
+	}
+
+}