在本地模式下使用scala 2.12.3运行以下spark mllib时，遇到以下错误lambda无法序列化
任何投入将不胜感激？ （对我来说，迁移到scala 2.11上不是一种选择）可以让我知道如何避免此问题吗？谢谢
import java.io.FileWriter
import org.apache.spark.SparkConf
import org.apache.spark.ml.Pipeline
import org.apache.spark.ml.evaluation.RegressionEvaluator
import org.apache.spark.ml.feature.StringIndexer
import org.apache.spark.ml.feature.VectorAssembler
import org.apache.spark.ml.regression.LinearRegression
import org.apache.spark.sql.SparkSession
import org.apache.spark.sql.types.DoubleType
import org.apache.spark.sql.types.IntegerType
import org.apache.spark.sql.types.StringType
import org.apache.spark.sql.types.StructField
import org.apache.spark.sql.types.StructType
import org.apache.spark.sql.types.TimestampType
import java.util.concurrent.atomic.AtomicBoolean
object MLAnalyzer {
val conf = new SparkConf().setMaster("local[2]").set("deploy-mode", "client").set("spark.driver.bindAddress", "127.0.0.1")
.set("spark.broadcast.compress", "false")
.setAppName("local-spark-kafka-consumer-client")
val spark = SparkSession
.builder()
.config(conf)
.getOrCreate()
def main(args: Array[String]): Unit = {
process
}
def process():Unit= {
// training data
val filePath = "/home/vagrant/Desktop/Workspaces/SparkMachineLearning/sparkML/src/main/resources/train_pooling.csv"
val modelPath = "file:///home/vagrant/Downloads/medium-articles-master/titanic_spark/training_batch/src/main/resources/poolSessionModelRecent.model"
val schema = StructType(
Array(
StructField("PACKAGE_KEY", StringType),
StructField("MOST_IDLE", IntegerType),
StructField("MAX_WAIT", IntegerType),
StructField("IDLE_COUNT", IntegerType),
StructField("APPLICATION", StringType),
StructField("LONGEST_WAIT", IntegerType),
StructField("TIMEOUTS", IntegerType),
StructField("LAST_ACCESS", TimestampType),
StructField("MOST_ACTIVE", IntegerType),
StructField("MAX_ACTIVE", IntegerType),
StructField("MAX_IDLE", IntegerType),
StructField("ACTIVE_COUNT", IntegerType),
StructField("FACTOR_LOAD", DoubleType)))
while (true) {
Thread.sleep(100)
// read the raw data
var df_raw = spark
.read
.option("header", "true")
// .option("inferSchema","true")
.schema(schema)
.csv(filePath)
df_raw = df_raw.drop(df_raw.col("PACKAGE_KEY"))
df_raw = df_raw.drop(df_raw.col("MOST_IDLE"))
df_raw = df_raw.drop(df_raw.col("MAX_IDLE"))
df_raw = df_raw.drop(df_raw.col("MOST_ACTIVE"))
df_raw = df_raw.drop(df_raw.col("LAST_ACCESS"))
df_raw = df_raw.drop(df_raw.col("APPLICATION"))
df_raw = df_raw.drop(df_raw.col("MAX_WAIT"))
// fill all na values with 0
val df = df_raw.na.fill(0)
val packageKeyIndexer = new StringIndexer()
.setInputCol("PACKAGE_KEY")
.setOutputCol("PackageIndex")
.setHandleInvalid("keep")
// create the feature vector
val vectorAssembler = new VectorAssembler()
.setInputCols(Array("IDLE_COUNT", "TIMEOUTS", "ACTIVE_COUNT" /*, "TOTAL_REQUEST_COUNT"*/ ))
.setOutputCol("features_intermediate")
import org.apache.spark.ml.feature.StandardScaler
val scaler = new StandardScaler().setWithMean(true).setWithStd(true).setInputCol("features_intermediate").setOutputCol("features")
var pipeline: Pipeline = null
// if (lr1 == null) {
val lr =
new LinearRegression()
.setMaxIter(100)
.setRegParam(0.1)
.setElasticNetParam(0.8)
//.setFeaturesCol("features") // setting features column
.setLabelCol("FACTOR_LOAD") // setting label column
// create the pipeline with the steps
pipeline = new Pipeline().setStages(Array( /*genderIndexer, cabinIndexer, embarkedIndexer,*/ vectorAssembler, scaler, lr))
// create the model following the pipeline steps
val cvModel = pipeline.fit(df)
// save the model
cvModel.write.overwrite.save(modelPath)
var testschema = StructType(
Array(
// StructField("PACKAGE_KEY", StringType),
StructField("IDLE_COUNT", IntegerType),
StructField("TIMEOUTS", IntegerType),
StructField("ACTIVE_COUNT", IntegerType)))
val df_raw1 = spark
.read
// .option("header", "true")
.schema(testschema)
.csv("/home/vagrant/Desktop/Workspaces/SparkMachineLearning/sparkML/src/main/resources/test_pooling.csv")
// fill all na values with 0
val df1 = df_raw1.na.fill(0)
val evaluator = new RegressionEvaluator().setMetricName("rmse").setLabelCol("prediction")
var rmse = evaluator.evaluate(cvModel.transform(df1))
import org.apache.spark.sql.functions._
import spark.implicits._
val extracted = cvModel.transform(df1)
val prediction = extracted.select("prediction").map(r => r(0).asInstanceOf[Double]).collect()
if (prediction != null && prediction.length > 0) {
val avg = prediction.sum / prediction.length
val pw: FileWriter = new FileWriter("/home/vagrant/Desktop/Workspaces/SparkMachineLearning/sparkML/src/main/resources/result.csv");
pw.append(avg.toString)
pw.flush()
pw.close()
println("completed modelling process")
} else {
//do nothing
}
}
}
}
给我以下错误
Caused by: java.io.NotSerializableException: scala.runtime.LazyRef
Serialization stack:
- object not serializable (class: scala.runtime.LazyRef, value: LazyRef thunk)
- element of array (index: 2)
- array (class [Ljava.lang.Object;, size 3)
- field (class: java.lang.invoke.SerializedLambda, name: capturedArgs, type: class [Ljava.lang.Object;)
- object (class java.lang.invoke.SerializedLambda, SerializedLambda[capturingClass=class org.apache.spark.sql.catalyst.expressions.ScalaUDF, functionalInterfaceMethod=scala/Function1.apply:(Ljava/lang/Object;)Ljava/lang/Object;, implementation=invokeStatic org/apache/spark/sql/catalyst/expressions/ScalaUDF.$anonfun$f$2:(Lscala/Function1;Lorg/apache/spark/sql/catalyst/expressions/Expression;Lscala/runtime/LazyRef;Lorg/apache/spark/sql/catalyst/InternalRow;)Ljava/lang/Object;, instantiatedMethodType=(Lorg/apache/spark/sql/catalyst/InternalRow;)Ljava/lang/Object;, numCaptured=3])
- writeReplace data (class: java.lang.invoke.SerializedLambda)
- object (class org.apache.spark.sql.catalyst.expressions.ScalaUDF$$Lambda$2280/878458383, org.apache.spark.sql.catalyst.expressions.ScalaUDF$$Lambda$2280/878458383@65af23c0)
- field (class: org.apache.spark.sql.catalyst.expressions.ScalaUDF, name: f, type: interface scala.Function1)
- object (class org.apache.spark.sql.catalyst.expressions.ScalaUDF, UDF(named_struct(IDLE_COUNT_double_vecAssembler_bc4ee3d99e56, cast(coalesce(IDLE_COUNT#1732, 0) as double), TIMEOUTS_double_vecAssembler_bc4ee3d99e56, cast(coalesce(TIMEOUTS#1735, 0) as double), ACTIVE_COUNT_double_vecAssembler_bc4ee3d99e56, cast(coalesce(ACTIVE_COUNT#1740, 0) as double))))
- field (class: org.apache.spark.sql.catalyst.expressions.Alias, name: child, type: class org.apache.spark.sql.catalyst.expressions.Expression)
- object (class org.apache.spark.sql.catalyst.expressions.Alias, UDF(named_struct(IDLE_COUNT_double_vecAssembler_bc4ee3d99e56, cast(coalesce(IDLE_COUNT#1732, 0) as double), TIMEOUTS_double_vecAssembler_bc4ee3d99e56, cast(coalesce(TIMEOUTS#1735, 0) as double), ACTIVE_COUNT_double_vecAssembler_bc4ee3d99e56, cast(coalesce(ACTIVE_COUNT#1740, 0) as double))) AS features_intermediate#1839)
- element of array (index: 0)
答案 0 :(得分：1)
升级到Scala 2.12.8解决了该问题。虽然不确定根本原因。