flink

src/main/java/demo/SocketTextStreamWordCount.java

+package demo;
+
+import org.apache.flink.api.common.functions.FlatMapFunction;
+import org.apache.flink.api.java.tuple.Tuple2;
+import org.apache.flink.streaming.api.datastream.DataStreamSource;
+import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator;
+import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
+import org.apache.flink.util.Collector;
+
+public class SocketTextStreamWordCount {
+
+    public static void main(String[] args) throws Exception {
+        //参数检查
+        if (args.length != 2) {
+            System.err.println("USAGE:\nSocketTextStreamWordCount <hostname> <port>");
+            return;
+        }
+
+        String hostname = args[0];
+        Integer port = Integer.parseInt(args[1]);
+
+
+        // set up the streaming execution environment
+        final StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
+
+        //获取数据
+        DataStreamSource<String> stream = env.socketTextStream(hostname, port);
+
+        //计数
+        SingleOutputStreamOperator<Tuple2<String, Integer>> sum = stream.flatMap(new LineSplitter())
+                .keyBy(0)
+                .sum(1);
+
+        sum.print();
+
+        env.execute("Java WordCount from SocketTextStream Example");
+    }
+
+    public static final class LineSplitter implements FlatMapFunction<String, Tuple2<String, Integer>> {
+        @Override
+        public void flatMap(String s, Collector<Tuple2<String, Integer>> collector) {
+            String[] tokens = s.toLowerCase().split("\\W+");
+
+            for (String token: tokens) {
+                if (token.length() > 0) {
+                    collector.collect(new Tuple2<String, Integer>(token, 1));
+                }
+            }
+        }
+    }
+}