如何使用flink打印文件中的总行数

import org.apache.flink.api.common.functions.FlatMapFunction;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.api.java.utils.ParameterTool;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.util.Collector;

public class FileLineCount {
    public static void main(String[] args) throws Exception {
        // 创建执行环境
        final StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();

        // 读取文件内容
        DataStream<String> text = env.readTextFile("path/to/your/file.txt");

        // 统计总行数
        DataStream<Tuple2<String, Integer>> counts = text.flatMap(new LineCount())
                .keyBy(0)
                .sum(1);

        // 打印结果
        counts.print();

        // 执行任务
        env.execute("File Line Count");
    }

    public static final class LineCount implements FlatMapFunction<String, Tuple2<String, Integer>> {
        @Override
        public void flatMap(String value, Collector<Tuple2<String, Integer>> out) {
            out.collect(new Tuple2<>("Total Lines", 1));
        }
    }
}