Add Kubevirt Port and Instance classes with CURD interfaces

Change-Id: I1afbba8a04bc1872cc1c086f2e3a15620533d517
diff --git a/apps/kubevirt-networking/api/src/main/java/org/onosproject/kubevirtnetworking/api/DefaultKubevirtInstance.java b/apps/kubevirt-networking/api/src/main/java/org/onosproject/kubevirtnetworking/api/DefaultKubevirtInstance.java
new file mode 100644
index 0000000..13b94ce
--- /dev/null
+++ b/apps/kubevirt-networking/api/src/main/java/org/onosproject/kubevirtnetworking/api/DefaultKubevirtInstance.java
@@ -0,0 +1,133 @@
+/*
+ * Copyright 2021-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.kubevirtnetworking.api;
+
+import com.google.common.base.MoreObjects;
+import com.google.common.collect.ImmutableSet;
+
+import java.util.Objects;
+import java.util.Set;
+
+import static com.google.common.base.Preconditions.checkArgument;
+
+public final class DefaultKubevirtInstance implements KubevirtInstance {
+
+    private static final String NOT_NULL_MSG = "Instance % cannot be null";
+
+    private final String uid;
+    private final String name;
+    private final Set<KubevirtPort> ports;
+
+    /**
+     * Default constructor.
+     *
+     * @param uid       UID
+     * @param name      name of instance
+     * @param ports     set of ports associated with the instance
+     */
+    public DefaultKubevirtInstance(String uid, String name, Set<KubevirtPort> ports) {
+        this.uid = uid;
+        this.name = name;
+        this.ports = ports;
+    }
+
+    @Override
+    public String uid() {
+        return uid;
+    }
+
+    @Override
+    public String name() {
+        return name;
+    }
+
+    @Override
+    public Set<KubevirtPort> ports() {
+        return ImmutableSet.copyOf(ports);
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+        DefaultKubevirtInstance that = (DefaultKubevirtInstance) o;
+        return uid.equals(that.uid) && name.equals(that.name) && ports.equals(that.ports);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(uid, name, ports);
+    }
+
+    @Override
+    public String toString() {
+        return MoreObjects.toStringHelper(this)
+                .add("uid", uid)
+                .add("name", name)
+                .add("ports", ports)
+                .toString();
+    }
+
+    /**
+     * Returns new builder instance.
+     *
+     * @return kubevirt port builder
+     */
+    public static Builder builder() {
+        return new Builder();
+    }
+
+    /**
+     * Default builder implementation.
+     */
+    public static final class Builder implements KubevirtInstance.Builder {
+
+        private String uid;
+        private String name;
+        private Set<KubevirtPort> ports;
+
+        @Override
+        public KubevirtInstance build() {
+            checkArgument(uid != null, NOT_NULL_MSG, "UID");
+            checkArgument(name != null, NOT_NULL_MSG, "name");
+            checkArgument(ports != null, NOT_NULL_MSG, "ports");
+
+            return new DefaultKubevirtInstance(uid, name, ports);
+        }
+
+        @Override
+        public Builder uid(String uid) {
+            this.uid = uid;
+            return this;
+        }
+
+        @Override
+        public Builder name(String name) {
+            this.name = name;
+            return this;
+        }
+
+        @Override
+        public Builder ports(Set<KubevirtPort> ports) {
+            this.ports = ports;
+            return this;
+        }
+    }
+}