如何在scala中从键获取值，从map reduce作业获取值

val map = Map("key1" -> "value1", "key2" -> "value2")
val valueOption = map.get("key1")
valueOption match {
  case Some(value) => println(value) // 输出：value1
  case None => println("Key not found")
}

val map = Map("key1" -> "value1", "key2" -> "value2")
val value = map("key1")
println(value) // 输出：value1

val map = Map("key1" -> "value1", "key2" -> "value2")
val value = map.getOrElse("key1", "default")
println(value) // 输出：value1

import org.apache.hadoop.fs.Path
import org.apache.hadoop.io.{IntWritable, Text}
import org.apache.hadoop.mapreduce.{Job, Mapper, Reducer}
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat

class MyMapper extends Mapper[Object, Text, Text, IntWritable] {
  private val word = new Text()
  private val count = new IntWritable(1)

  override def map(key: Object, value: Text, context: Mapper[Object, Text, Text, IntWritable]#Context): Unit = {
    val line = value.toString
    val words = line.split("\\s+")
    for (word <- words) {
      this.word.set(word)
      context.write(this.word, this.count)
    }
  }
}

class MyReducer extends Reducer[Text, IntWritable, Text, IntWritable] {
  private val result = new IntWritable()

  override def reduce(key: Text, values: java.lang.Iterable[IntWritable], context: Reducer[Text, IntWritable, Text, IntWritable]#Context): Unit = {
    val sum = values.asScala.map(_.get()).sum
    this.result.set(sum)
    context.write(key, this.result)
  }
}

object WordCount {
  def main(args: Array[String]): Unit = {
    val job = Job.getInstance()
    job.setJarByClass(WordCount.getClass)
    job.setMapperClass(classOf[MyMapper])
    job.setCombinerClass(classOf[MyReducer])
    job.setReducerClass(classOf[MyReducer])
    job.setOutputKeyClass(classOf[Text])
    job.setOutputValueClass(classOf[IntWritable])
    FileInputFormat.addInputPath(job, new Path(args(0)))
    FileOutputFormat.setOutputPath(job, new Path(args(1)))
    System.exit(if (job.waitForCompletion(true)) 0 else 1)
  }
}