[ONOS-7051] Support for P4Runtime meters

Change-Id: Id71374af65aeb84b71636b4ec230dc6001a77a8b
diff --git a/core/api/src/main/java/org/onosproject/net/pi/runtime/PiMeterCellConfig.java b/core/api/src/main/java/org/onosproject/net/pi/runtime/PiMeterCellConfig.java
new file mode 100644
index 0000000..96ba124
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/net/pi/runtime/PiMeterCellConfig.java
@@ -0,0 +1,152 @@
+/*
+ * Copyright 2017-present Open Networking Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.net.pi.runtime;
+
+import com.google.common.annotations.Beta;
+import com.google.common.base.MoreObjects;
+import com.google.common.base.Objects;
+import com.google.common.collect.ImmutableList;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+/**
+ * Configuration of a meter cell of a protocol-independent pipeline.
+ */
+@Beta
+public final class PiMeterCellConfig implements PiEntity {
+
+    private final PiMeterCellId cellId;
+    private final ImmutableList<PiMeterBand> piMeterBands;
+
+    /**
+     * Creates a new meter cell configuration for the given cell identifier and meter bands.
+     *
+     * @param cellId  meter cell identifier
+     * @param piMeterBands meter bands
+     */
+    private PiMeterCellConfig(PiMeterCellId cellId, Collection<PiMeterBand> piMeterBands) {
+        this.cellId = cellId;
+        this.piMeterBands = ImmutableList.copyOf(piMeterBands);
+    }
+
+    /**
+     * Returns the cell identifier.
+     *
+     * @return cell identifier
+     */
+    public PiMeterCellId cellId() {
+        return cellId;
+    }
+
+    /**
+     * Returns the collection of bands of this cell.
+     *
+     * @return meter bands
+     */
+    public Collection<PiMeterBand> meterBands() {
+        return piMeterBands;
+    }
+
+    @Override
+    public PiEntityType piEntityType() {
+        return PiEntityType.METER_CELL_CONFIG;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (!(o instanceof PiMeterCellConfig)) {
+            return false;
+        }
+        PiMeterCellConfig that = (PiMeterCellConfig) o;
+
+        return piMeterBands.containsAll((that.piMeterBands)) &&
+                piMeterBands.size() == that.piMeterBands.size() &&
+                Objects.equal(cellId, that.cellId);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hashCode(cellId, piMeterBands);
+    }
+
+    @Override
+    public String toString() {
+        return MoreObjects.toStringHelper(this)
+                .add("cellId", cellId)
+                .add("meterBands", piMeterBands)
+                .toString();
+    }
+
+    /**
+     * Returns a meter cell configuration builder.
+     *
+     * @return a new builder
+     */
+    public static PiMeterCellConfig.Builder builder() {
+        return new PiMeterCellConfig.Builder();
+    }
+
+    public static final class Builder {
+        private  PiMeterCellId cellId;
+        private List<PiMeterBand> bands = new ArrayList<>();
+
+
+        private Builder() {
+            // Hides constructor.
+        }
+
+        /**
+         * Sets the meter cell identifier for this meter.
+         *
+         * @param meterCellId meter cell identifier
+         * @return this
+         */
+        public PiMeterCellConfig.Builder withMeterCellId(PiMeterCellId meterCellId) {
+            this.cellId = meterCellId;
+            return this;
+        }
+
+
+        /**
+         * Sets a meter band of this meter.
+         *
+         * @param band meter band
+         * @return this
+         */
+        public PiMeterCellConfig.Builder withMeterBand(PiMeterBand band) {
+            this.bands.add(band);
+            return this;
+        }
+
+        /**
+         * Builds the meter cell configuration.
+         *
+         * @return a new meter cell configuration
+         */
+        public PiMeterCellConfig build() {
+            checkNotNull(cellId);
+            return new PiMeterCellConfig(cellId, bands);
+        }
+    }
+}