java spark 实现spark.ml.feature.ChiSqSelector功能，最后打印出筛选结果和被筛选出的列名？

好的，可以使用以下代码来实现：

import org.apache.spark.ml.feature.ChiSqSelector;
import org.apache.spark.ml.feature.ChiSqSelectorModel;
import org.apache.spark.ml.feature.VectorAssembler;
import org.apache.spark.ml.linalg.Vector;
import org.apache.spark.sql.Dataset;
import org.apache.spark.sql.Row;
import org.apache.spark.sql.SparkSession;
import org.apache.spark.sql.functions;

public class ChiSqSelectorExample {
    public static void main(String[] args) {
        SparkSession spark = SparkSession.builder()
                .appName("ChiSqSelectorExample")
                .master("local[*]")
                .getOrCreate();

        // 读取数据集
        Dataset<Row> data = spark.read().format("csv")
                .option("header", "true")
                .option("inferSchema", "true")
                .load("data.csv");

        // 将特征列组装成一个向量列
        VectorAssembler assembler = new VectorAssembler()
                .setInputCols(new String[]{"col1", "col2", "col3"})
                .setOutputCol("features");
        Dataset<Row> df = assembler.transform(data).select("features", "label");

        // 运行 ChiSqSelector
        ChiSqSelector selector = new ChiSqSelector()
                .setNumTopFeatures(2)
                .setFeaturesCol("features")
                .setLabelCol("label")
                .setOutputCol("selectedFeatures");
        ChiSqSelectorModel selectorModel = selector.fit(df);
        Dataset<Row> result = selectorModel.transform(df);

        // 打印筛选结果和被筛选出的列名
        Vector selectedFeatures = selectorModel.selectedFeatures();
        String[] inputCols = assembler.getInputCols();
        String[] selectedCols = new String[selectedFeatures.size()];
        for (int i = 0; i < selectedFeatures.size(); i++) {
            int index = (int) selectedFeatures.apply(i);
            selectedCols[i] = inputCols[index];
        }
        System.out.println("Selected columns: " + String.join(",", selectedCols));
        result.show();
    }
}

其中，`data.csv` 是数据集文件，需要替换成实际的数据集文件名；`col1`、`col2`、`col3` 是数据集中的特征列名，需要替换成实际的特征列名；`label` 是数据集中的标签列名，需要替换成实际的标签列名。运行程序后，会输出选择的特征列名和筛选结果。