在Apache Flink中按元组字段中的最大值过滤

// 导入所需的包
import org.apache.flink.api.common.functions.FilterFunction;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;

// 创建执行环境
StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();

// 创建包含元组的数据流
DataStream<Tuple2<String, Integer>> input = env.fromElements(
    new Tuple2<>("A", 10),
    new Tuple2<>("B", 20),
    new Tuple2<>("C", 15),
    new Tuple2<>("D", 25)
);

// 按元组字段中的最大值过滤
DataStream<Tuple2<String, Integer>> filtered = input.filter(new FilterFunction<Tuple2<String, Integer>>() {
    @Override
    public boolean filter(Tuple2<String, Integer> value) throws Exception {
        // 获取元组中的整数字段值
        int fieldValue = value.f1;
        // 判断是否为最大值
        return fieldValue == input.maxBy(1).collect().get(0).f1;
    }
});

// 打印过滤后的结果
filtered.print();

// 执行任务
env.execute();