Modify config Module impls to co-exist with blueprint

[controller.git] / opendaylight / config / config-api / src / main / java / org / opendaylight / controller / config / api / osgi / WaitingServiceTracker.java

diff --git a/opendaylight/config/config-api/src/main/java/org/opendaylight/controller/config/api/osgi/WaitingServiceTracker.java b/opendaylight/config/config-api/src/main/java/org/opendaylight/controller/config/api/osgi/WaitingServiceTracker.java
new file mode 100644 (file)
index 0000000..1549e6b
--- /dev/null
+++ b/opendaylight/config/config-api/src/main/java/org/opendaylight/controller/config/api/osgi/WaitingServiceTracker.java
@@ -0,0 +1,102 @@
+/*
+ * Copyright (c) 2016 Brocade Communications Systems, Inc. and others.  All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
+package org.opendaylight.controller.config.api.osgi;
+
+import java.util.concurrent.TimeUnit;
+import javax.annotation.Nonnull;
+import org.osgi.framework.BundleContext;
+import org.osgi.framework.Constants;
+import org.osgi.framework.InvalidSyntaxException;
+import org.osgi.util.tracker.ServiceTracker;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Tracker that waits for an OSGi service.
+ *
+ * @author Thomas Pantelis
+ */
+public final class WaitingServiceTracker<T> implements AutoCloseable {
+    private static final Logger LOG = LoggerFactory.getLogger(WaitingServiceTracker.class);
+    public static final long FIVE_MINUTES = TimeUnit.MILLISECONDS.convert(5, TimeUnit.MINUTES);
+
+    private final ServiceTracker<T, ?> tracker;
+    private final Class<T> serviceInterface;
+
+    private WaitingServiceTracker(Class<T> serviceInterface, ServiceTracker<T, ?> tracker) {
+        this.tracker = tracker;
+        this.serviceInterface = serviceInterface;
+    }
+
+    /**
+     * Waits for an OSGi services.
+     *
+     * @param timeoutInMillis the timeout in millis
+     * @return the service instance
+     * @throws ServiceNotFoundException if it times out or is interrupted
+     */
+    @SuppressWarnings("unchecked")
+    public T waitForService(long timeoutInMillis) throws ServiceNotFoundException {
+        try {
+            T service = (T) tracker.waitForService(timeoutInMillis);
+            if(service == null) {
+                throw new ServiceNotFoundException(String.format("OSGi Service %s was not found after %d ms",
+                        serviceInterface, timeoutInMillis));
+            }
+
+            return service;
+        } catch(InterruptedException e) {
+            throw new ServiceNotFoundException(String.format("Wait for OSGi service %s was interrrupted",
+                    serviceInterface));
+        }
+    }
+
+    /**
+     * Creates an instance.
+     *
+     * @param serviceInterface the service interface
+     * @param context the BundleContext
+     * @return new WaitingServiceTracker instance
+     */
+    public static <T> WaitingServiceTracker<T> create(@Nonnull Class<T> serviceInterface, @Nonnull BundleContext context) {
+        ServiceTracker<T, ?> tracker = new ServiceTracker<>(context, serviceInterface, null);
+        tracker.open();
+        return new WaitingServiceTracker<T>(serviceInterface, tracker);
+    }
+
+    /**
+     * Creates an instance.
+     *
+     * @param serviceInterface the service interface
+     * @param context the BundleContext
+     * @param filter the OSGi service filter
+     * @return new WaitingServiceTracker instance
+     */
+    public static <T> WaitingServiceTracker<T> create(@Nonnull Class<T> serviceInterface, @Nonnull BundleContext context,
+            @Nonnull String filter) {
+        String newFilter = String.format("(&(%s=%s)%s)", Constants.OBJECTCLASS, serviceInterface.getName(), filter);
+        try {
+            ServiceTracker<T, ?> tracker = new ServiceTracker<>(context, context.createFilter(newFilter), null);
+            tracker.open();
+            return new WaitingServiceTracker<T>(serviceInterface, tracker);
+        } catch(InvalidSyntaxException e) {
+            throw new IllegalArgumentException(String.format("Invalid OSGi filter %s", newFilter), e);
+        }
+    }
+
+    @Override
+    public void close() {
+        try {
+            tracker.close();
+        } catch(RuntimeException e) {
+            // The ServiceTracker could throw IllegalStateException if the BundleContext is already closed.
+            // This is benign so ignore it.
+            LOG.debug("Error closing ServiceTracker", e);
+        }
+    }
+}