[ONOS-6809] Implementation for packet out in p4Runtime

Change-Id: I873a1fd18529fe9fd41aa33f862298892ece7d1c
diff --git a/core/api/src/main/java/org/onosproject/net/pi/model/PiPipelineInterpreter.java b/core/api/src/main/java/org/onosproject/net/pi/model/PiPipelineInterpreter.java
index e71d910..25962ca 100644
--- a/core/api/src/main/java/org/onosproject/net/pi/model/PiPipelineInterpreter.java
+++ b/core/api/src/main/java/org/onosproject/net/pi/model/PiPipelineInterpreter.java
@@ -23,7 +23,7 @@
 import org.onosproject.net.flow.criteria.Criterion;
 import org.onosproject.net.packet.OutboundPacket;
 import org.onosproject.net.pi.runtime.PiHeaderFieldId;
-import org.onosproject.net.pi.runtime.PiPacketMetadata;
+import org.onosproject.net.pi.runtime.PiPacketOperation;
 import org.onosproject.net.pi.runtime.PiTableAction;
 import org.onosproject.net.pi.runtime.PiTableId;
 
@@ -79,15 +79,15 @@
             throws PiInterpreterException;
 
     /**
-     * Returns a collection of metadatas for a packet-out operation that are equivalent to
-     * the traffic treatment of the given OutboundPacket, for the given pipeline configuration.
+     * Returns a collection of packet operations equivalent to the given OutboundPacket, for the given
+     * pipeline configuration.
      *
      * @param packet   a ONOS outbound packet
      * @param pipeconf a pipeline configuration
-     * @return a collection of packet metadata
+     * @return a collection of packet operations
      * @throws PiInterpreterException if the packet treatments cannot be mapped to any metadata
      */
-    Collection<PiPacketMetadata> mapOutboundPacket(OutboundPacket packet, PiPipeconf pipeconf)
+    Collection<PiPacketOperation> mapOutboundPacket(OutboundPacket packet, PiPipeconf pipeconf)
             throws PiInterpreterException;
 
     /**
diff --git a/core/net/src/test/java/org/onosproject/net/pi/impl/MockInterpreter.java b/core/net/src/test/java/org/onosproject/net/pi/impl/MockInterpreter.java
index ddee2ca..14e698d 100644
--- a/core/net/src/test/java/org/onosproject/net/pi/impl/MockInterpreter.java
+++ b/core/net/src/test/java/org/onosproject/net/pi/impl/MockInterpreter.java
@@ -17,6 +17,7 @@
 package org.onosproject.net.pi.impl;
 
 import com.google.common.collect.ImmutableBiMap;
+import com.google.common.collect.ImmutableList;
 import org.onlab.util.ImmutableByteSequence;
 import org.onosproject.net.PortNumber;
 import org.onosproject.net.driver.AbstractHandlerBehaviour;
@@ -31,7 +32,7 @@
 import org.onosproject.net.pi.runtime.PiActionParam;
 import org.onosproject.net.pi.runtime.PiActionParamId;
 import org.onosproject.net.pi.runtime.PiHeaderFieldId;
-import org.onosproject.net.pi.runtime.PiPacketMetadata;
+import org.onosproject.net.pi.runtime.PiPacketOperation;
 import org.onosproject.net.pi.runtime.PiTableAction;
 import org.onosproject.net.pi.runtime.PiTableId;
 
@@ -102,9 +103,9 @@
     }
 
     @Override
-    public Collection<PiPacketMetadata> mapOutboundPacket(OutboundPacket packet, PiPipeconf pipeconf)
+    public Collection<PiPacketOperation> mapOutboundPacket(OutboundPacket packet, PiPipeconf pipeconf)
             throws PiInterpreterException {
-        return null;
+        return ImmutableList.of();
     }
 
     /**