BUG-5280: introduce Request/Response and related concepts

[controller.git] / opendaylight / md-sal / cds-access-api / src / main / java / org / opendaylight / controller / cluster / access / concepts / Request.java

diff --git a/opendaylight/md-sal/cds-access-api/src/main/java/org/opendaylight/controller/cluster/access/concepts/Request.java b/opendaylight/md-sal/cds-access-api/src/main/java/org/opendaylight/controller/cluster/access/concepts/Request.java
new file mode 100644 (file)
index 0000000..d0d6324
--- /dev/null
+++ b/opendaylight/md-sal/cds-access-api/src/main/java/org/opendaylight/controller/cluster/access/concepts/Request.java
@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2016 Cisco 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.cluster.access.concepts;
+
+import akka.actor.ActorRef;
+import com.google.common.annotations.Beta;
+import com.google.common.base.MoreObjects.ToStringHelper;
+import com.google.common.base.Preconditions;
+import javax.annotation.Nonnull;
+import org.opendaylight.controller.cluster.access.ABIVersion;
+import org.opendaylight.yangtools.concepts.WritableIdentifier;
+
+/**
+ * A request message concept. Upon receipt of this message, the recipient will respond with either
+ * a {@link RequestSuccess} or a {@link RequestFailure} message.
+ *
+ * @author Robert Varga
+ *
+ * @param <T> Target identifier type
+ * @param <C> Message type
+ */
+@Beta
+public abstract class Request<T extends WritableIdentifier, C extends Request<T, C>> extends Message<T, C> {
+    private static final long serialVersionUID = 1L;
+    private final ActorRef replyTo;
+
+    protected Request(final @Nonnull T target, final long sequence, final long retry, final @Nonnull ActorRef replyTo) {
+        super(target, sequence, retry);
+        this.replyTo = Preconditions.checkNotNull(replyTo);
+    }
+
+    protected Request(final @Nonnull C request, final @Nonnull ABIVersion version) {
+        super(request, version);
+        this.replyTo = Preconditions.checkNotNull(request.getReplyTo());
+    }
+
+    protected Request(final C request, final long retry) {
+        super(request, retry);
+        this.replyTo = Preconditions.checkNotNull(request.getReplyTo());
+    }
+
+    /**
+     * Return the return address where responses to this request should be directed to.
+     *
+     * @return Original requestor
+     */
+    public final @Nonnull ActorRef getReplyTo() {
+        return replyTo;
+    }
+
+    /**
+     * Return a {@link RequestFailure} for this request, caused by a {@link RequestException}.
+     *
+     * @param cause Failure cause
+     * @return {@link RequestFailure} corresponding to this request
+     */
+    public abstract @Nonnull RequestFailure<T, ?> toRequestFailure(final @Nonnull RequestException cause);
+
+    @Override
+    protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
+        return super.addToStringAttributes(toStringHelper).add("replyTo", replyTo);
+    }
+
+    @Override
+    protected abstract AbstractRequestProxy<T, C> externalizableProxy(@Nonnull ABIVersion version);
+}