STS-2952: JMX operations should be wrapped in a Job

plugins/org.springframework.ide.eclipse.beans.ui.livegraph/src/org/springframework/ide/eclipse/beans/ui/livegraph/model/LiveBeansModelGenerator.java

@@ -15,6 +15,8 @@
 import java.util.Collection;
 import java.util.HashMap;
 import java.util.Map;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
 
 import javax.management.InstanceNotFoundException;
 import javax.management.MBeanServerConnection;
@@ -26,8 +28,10 @@
 import javax.management.remote.JMXServiceURL;
 
 import org.eclipse.core.runtime.CoreException;
+import org.eclipse.core.runtime.IProgressMonitor;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.Status;
+import org.eclipse.core.runtime.jobs.Job;
 import org.json.JSONException;
 import org.springframework.context.support.LiveBeansViewMBean;
 import org.springframework.ide.eclipse.beans.ui.livegraph.LiveGraphUiPlugin;
@@ -44,8 +48,10 @@ public class LiveBeansModelGenerator {
 	/**
 	 * This method will not attempt to close the given {@link JMXConnector}. If
 	 * the connection has failed, clients may capture the thrown
-	 * {@link CoreException} and inform the user. This method will never return
-	 * a <code>null</code> {@link LiveBeansModel}
+	 * {@link CoreException} and inform the user. This method is not UI safe,
+	 * and may block the UI with network operations. Clients will need to call
+	 * this method from a non-blocking {@link Job}. This method will never
+	 * return a <code>null</code> {@link LiveBeansModel}
 	 * 
 	 * @param connector
 	 * @param appName
@@ -87,7 +93,8 @@ public static LiveBeansModel connectToModel(JMXConnector connector, String appNa
 	 * This method will attempt to create a {@link JMXConnector} from the given
 	 * parameters and will close it when it is finished. If the connection has
 	 * failed, clients may capture the thrown {@link CoreException} and inform
-	 * the user. This method will never return a <code>null</code>
+	 * the user. This method is UI safe, and will not block the UI with network
+	 * operations. It will never return a <code>null</code>
 	 * {@link LiveBeansModel}
 	 * 
 	 * @param serviceUrl
@@ -98,24 +105,52 @@ public static LiveBeansModel connectToModel(JMXConnector connector, String appNa
 	 * failed
 	 * @throws CoreException
 	 */
-	public static LiveBeansModel connectToModel(String serviceUrl, String username, String password, String appName)
-			throws CoreException {
-		JMXConnector connector = null;
-		try {
-			connector = setupConnector(serviceUrl, username, password);
-			return connectToModel(connector, appName);
-		}
-		finally {
-			if (connector != null) {
+	public static LiveBeansModel connectToModel(final String serviceUrl, final String username, final String password,
+			final String appName) throws CoreException {
+		final CountDownLatch latch = new CountDownLatch(1);
+		final LiveBeansModel[] result = new LiveBeansModel[1];
+		final CoreException[] status = new CoreException[1];
+
+		Job jmxOperation = new Job("Executing Server Command") {
+			@Override
+			protected IStatus run(IProgressMonitor monitor) {
+				JMXConnector connector = null;
 				try {
-					connector.close();
+					connector = setupConnector(serviceUrl, username, password);
+					result[0] = connectToModel(connector, appName);
+				}
+				catch (CoreException e) {
+					status[0] = e;
 				}
-				catch (IOException e) {
-					StatusHandler.log(new Status(IStatus.ERROR, LiveGraphUiPlugin.PLUGIN_ID,
-							"An error occurred while closing connection to server.", e));
+				finally {
+					latch.countDown();
+					if (connector != null) {
+						try {
+							connector.close();
+						}
+						catch (IOException e) {
+							StatusHandler.log(new Status(IStatus.ERROR, LiveGraphUiPlugin.PLUGIN_ID,
+									"An error occurred while closing connection to server.", e));
+						}
+					}
 				}
+				return Status.OK_STATUS;
 			}
+		};
+		jmxOperation.schedule();
+
+		try {
+			if (latch.await(30, TimeUnit.SECONDS)) {
+				if (status[0] != null) {
+					throw status[0];
+				}
+				return result[0];
+			}
+		}
+		catch (InterruptedException e) {
+			// swallowed
 		}
+		return new LiveBeansModel();
 	}
 
 	private static LiveBeansModel generateModel(LiveBeansViewMBean mbean, String appName) throws CoreException {