1 files changed, 42 insertions, 0 deletions
diff --git a/model/src/main/java/org/onap/policy/apex/model/utilities/comparison/KeyComparer.java b/model/src/main/java/org/onap/policy/apex/model/utilities/comparison/KeyComparer.java
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+++ b/model/src/main/java/org/onap/policy/apex/model/utilities/comparison/KeyComparer.java
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+/*
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
+ * ================================================================================
+ * 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.
+ * 
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.apex.model.utilities.comparison;
+
+/**
+ * This class compares two keys and returns their differences. It is used in bulk comparisons in models where maps of
+ * keys are being compared. The {@link KeyComparer} that is returned does the actual comparison
+ *
+ * @author Liam Fallon (liam.fallon@ericsson.com)
+ * @param <K> the type of key being compared
+ */
+public class KeyComparer<K> {
+
+    /**
+     * Compare two keys and return their differences.
+     *
+     * @param leftKey The left key of the comparison
+     * @param rightKey The right key of the comparison
+     * @return The difference between the keys
+     */
+    public KeyDifference<K> compareKeys(final K leftKey, final K rightKey) {
+        return new KeyDifference<>(leftKey, rightKey);
+    }
+}