1 files changed, 50 insertions, 0 deletions
diff --git a/src/main/java/org/onap/dcae/multiplestreamreducer/MultipleStreamReducer.java b/src/main/java/org/onap/dcae/multiplestreamreducer/MultipleStreamReducer.java
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index 00000000..c03ab6bb
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+++ b/src/main/java/org/onap/dcae/multiplestreamreducer/MultipleStreamReducer.java
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+/*
+ * ============LICENSE_START=======================================================
+ * PROJECT
+ * ================================================================================
+ * Copyright (C) 2021 Nokia. 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.
+ * ============LICENSE_END=========================================================
+ */
+package org.onap.dcae.multiplestreamreducer;
+
+import io.vavr.Tuple2;
+import io.vavr.collection.Map;
+
+public class MultipleStreamReducer {
+
+    /**
+     * Converts configuration from: "one domain many streams"
+     * to: "one domain one stream"
+     *
+     * @param map domain to streams configuration
+     * @return configuration - one domain one stream
+     */
+    public Map<String, String> reduce(Map<String, String[]> map) {
+        return map.toStream()
+                .toMap(Tuple2::_1, v -> v._2[0]);
+    }
+
+    /**
+     * Information about the current match: domain to stream
+     *
+     * @param domainToStreamConfig domain to stream configuration
+     * @return current domain to stream information
+     */
+    public String getDomainToStreamsInfo(Map<String, String> domainToStreamConfig) {
+        return domainToStreamConfig.map(v -> "Domain: " +
+                v._1 + " has active stream: " + v._2 + System.lineSeparator())
+                .reduce((a, b) -> a + b);
+    }
+}