动态生成具有filter、withColumnRenamed和coalesce condition Scala Spark的代码

import org.apache.spark.sql.{DataFrame, SparkSession}
import org.apache.spark.sql.functions._

val spark = SparkSession.builder()
  .appName("Dynamic Spark Code")
  .master("local")
  .getOrCreate()

def generateDynamicCode(filterCondition: String, renameColumn: String, coalesceColumns: Array[String]): DataFrame => DataFrame = {
  (df: DataFrame) => {
    var resultDF = df

    // 添加filter条件
    if (filterCondition.nonEmpty) {
      resultDF = resultDF.filter(filterCondition)
    }

    // 重命名列
    if (renameColumn.nonEmpty) {
      val columnNames = resultDF.columns
      val renamedColumns = columnNames.map(name => if (name == renameColumn) s"${name}_renamed" else name)
      resultDF = resultDF.toDF(renamedColumns: _*)
    }

    // 合并列
    if (coalesceColumns.nonEmpty) {
      resultDF = resultDF.withColumn("coalesced_column", coalesce(coalesceColumns.map(col): _*))
    }

    resultDF
  }
}

val inputDF = spark.read.csv("input.csv") // 替换为实际的输入数据源

val filterCondition = "age > 18" // 替换为实际的filter条件
val renameColumn = "name" // 替换为实际的重命名列名
val coalesceColumns = Array("col1", "col2") // 替换为实际的合并列名数组

val dynamicCode = generateDynamicCode(filterCondition, renameColumn, coalesceColumns)
val outputDF = dynamicCode(inputDF)