[BAEL-16003] Moving article out of libraries (& flink from libraries-data) into libraries-data-2

libraries-data-2/src/main/com/baeldung/flink/LineSplitter.java

@@ -0,0 +1,18 @@
+package com.baeldung.flink;
+
+import org.apache.flink.api.common.functions.FlatMapFunction;
+import org.apache.flink.api.java.tuple.Tuple2;
+import org.apache.flink.util.Collector;
+
+import java.util.stream.Stream;
+
+@SuppressWarnings("serial")
+public class LineSplitter implements FlatMapFunction<String, Tuple2<String, Integer>> {
+
+    @Override
+    public void flatMap(String value, Collector<Tuple2<String, Integer>> out) {
+
+        String[] tokens = value.toLowerCase().split("\\W+");
+        Stream.of(tokens).filter(t -> t.length() > 0).forEach(token -> out.collect(new Tuple2<>(token, 1)));
+    }
+}