[ONOS-5084],[ONOS-5083] YANG schema registry for YMS

Change-Id: I88394307cb9be30237be0bb17e013d7af88a607c
diff --git a/apps/yms/app/src/main/java/org/onosproject/yms/app/ysr/DefaultYangModuleInformation.java b/apps/yms/app/src/main/java/org/onosproject/yms/app/ysr/DefaultYangModuleInformation.java
new file mode 100644
index 0000000..79778f7
--- /dev/null
+++ b/apps/yms/app/src/main/java/org/onosproject/yms/app/ysr/DefaultYangModuleInformation.java
@@ -0,0 +1,111 @@
+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * 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.yms.app.ysr;
+
+import com.google.common.collect.ImmutableList;
+import org.onosproject.yms.ysr.YangModuleIdentifier;
+import org.onosproject.yms.ysr.YangModuleInformation;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+
+import static com.google.common.base.MoreObjects.toStringHelper;
+
+/**
+ * Representation of default YANG module information.
+ */
+class DefaultYangModuleInformation implements YangModuleInformation {
+
+    private final YangModuleIdentifier moduleIdentifier;
+    private final String nameSpace;
+    private final List<String> features;
+    private final List<YangModuleIdentifier> subModuleIdentifiers;
+
+    /**
+     * Creates an instance of YANG module information.
+     *
+     * @param moduleIdentifier module identifier
+     * @param nameSpace        name space of module
+     */
+    DefaultYangModuleInformation(YangModuleIdentifier moduleIdentifier,
+                                 String nameSpace) {
+        this.moduleIdentifier = moduleIdentifier;
+        this.nameSpace = nameSpace;
+        subModuleIdentifiers = new ArrayList<>();
+        features = new ArrayList<>();
+    }
+
+    @Override
+    public YangModuleIdentifier moduleIdentifier() {
+        return moduleIdentifier;
+    }
+
+    @Override
+    public String namespace() {
+        return nameSpace;
+    }
+
+    @Override
+    public List<String> featureList() {
+        return ImmutableList.copyOf(features);
+    }
+
+    @Override
+    public List<YangModuleIdentifier> subModuleIdentifiers() {
+        return ImmutableList.copyOf(subModuleIdentifiers);
+    }
+
+    /**
+     * Adds to YANG sub module identifier list.
+     *
+     * @param subModuleIdentifier YANG sub module identifier
+     */
+    void addSubModuleIdentifiers(YangModuleIdentifier subModuleIdentifier) {
+        subModuleIdentifiers.add(subModuleIdentifier);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(moduleIdentifier, subModuleIdentifiers, nameSpace, features);
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+        if (obj instanceof DefaultYangModuleInformation) {
+            DefaultYangModuleInformation that = (DefaultYangModuleInformation) obj;
+            return Objects.equals(moduleIdentifier, that.moduleIdentifier) &&
+                    Objects.equals(nameSpace, that.nameSpace) &&
+                    Objects.equals(features, that.features) &&
+                    Objects.equals(subModuleIdentifiers, that.subModuleIdentifiers);
+        }
+        return false;
+    }
+
+    @Override
+    public String toString() {
+        return toStringHelper(this)
+                .add("yangModuleIdentifier", moduleIdentifier)
+                .add("nameSpace", nameSpace)
+                .add("features", features)
+                .add("yangModuleIdentifiers", subModuleIdentifiers)
+                .toString();
+    }
+}