1 files changed, 69 insertions, 0 deletions
diff --git a/yang-comparator/src/main/java/org/onap/modeling/yangkit/comparator/MaxElementsComparator.java b/yang-comparator/src/main/java/org/onap/modeling/yangkit/comparator/MaxElementsComparator.java
new file mode 100644
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--- /dev/null
+++ b/yang-comparator/src/main/java/org/onap/modeling/yangkit/comparator/MaxElementsComparator.java
@@ -0,0 +1,69 @@
+/*
+Copyright 2023 Huawei Technologies
+
+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.onap.modeling.yangkit.comparator;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.yangcentral.yangkit.model.api.stmt.MaxElements;
+
+
+public class MaxElementsComparator extends CommonYangStatementComparator<MaxElements> {
+
+    /**
+     *
+     * @param left       left statement
+     * @param right      right statement
+     * @return
+     */
+    @Override
+    protected List<CompatibilityRule.ChangeInfo> getChangeInfo(MaxElements left, MaxElements right) {
+        List<CompatibilityRule.ChangeInfo> changeInfos = new ArrayList<>();
+        if (left.isUnbounded() && !right.isUnbounded()) {
+            changeInfos.add(CompatibilityRule.ChangeInfo.REDUCE);
+        } else if (!left.isUnbounded() && right.isUnbounded()) {
+            changeInfos.add(CompatibilityRule.ChangeInfo.EXPAND);
+        } else if (!left.isUnbounded() && !right.isUnbounded()) {
+            if (left.getValue() < right.getValue()) {
+                changeInfos.add(CompatibilityRule.ChangeInfo.EXPAND);
+            } else if (left.getValue() > right.getValue()) {
+                changeInfos.add(CompatibilityRule.ChangeInfo.REDUCE);
+            }
+        }
+        if (super.getChangeInfo(left, right).contains(CompatibilityRule.ChangeInfo.SEQUENCE_CHANGED)) {
+            changeInfos.add(CompatibilityRule.ChangeInfo.SEQUENCE_CHANGED);
+        }
+        return changeInfos;
+    }
+
+    /**
+     *
+     * @param left       left statement
+     * @param right      right statement
+     * @param changeInfo
+     * @return
+     */
+    @Override
+    protected CompatibilityInfo defaultCompatibility(MaxElements left, MaxElements right,
+                                                     CompatibilityRule.ChangeInfo changeInfo) {
+        if (changeInfo == CompatibilityRule.ChangeInfo.REDUCE) {
+            return new CompatibilityInfo(CompatibilityRule.Compatibility.NBC, "the max-elements is reduced,"
+                    + "it's non-backward-compatible.");
+        }
+        return super.defaultCompatibility(left, right, changeInfo);
+    }
+}