java 查看类是从哪个jar包加载的

package com.jason

object FIndjar {
  def main(args: Array[String]): Unit = {
    val pd = classOf[org.apache.hadoop.mapreduce.TaskID].getProtectionDomain
    println("===="*)
    val cs = pd.getCodeSource
    System.out.println(cs.getLocation)
  }
}

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file:/C:/notos/software/spark/spark-2.1.-bin-hadoop2./jars/hadoop-mapreduce-client-core-2.6..jar