Hi , I meeting some issue when I try to read from some string coming from web service as an UDF string and register.
Here is the exception. java.lang.ClassCastException: cannot assign instance of scala.collection.immutable.List$SerializationProxy to field org.apache.spark.rdd.RDD.org$apache$spark$rdd$RDD$$dependencies_ of type scala.collection.Seq in instance of org.apache.spark.rdd.MapPartitionsRDD at java.io.ObjectStreamClass$FieldReflector.setObjFieldValues(ObjectStreamClass.java:2133) at java.io.ObjectStreamClass.setObjFieldValues(ObjectStreamClass.java:1305) at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:2251) at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2169) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2027) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1535) at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:2245) at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2169) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2027) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1535) at java.io.ObjectInputStream.readObject(ObjectInputStream.java:422) at scala.collection.immutable.List$SerializationProxy.readObject(List.scala:479) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:1058) at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2136) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2027) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1535) at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:2245) at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2169) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2027) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1535) at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:2245) at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2169) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2027) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1535) at java.io.ObjectInputStream.readObject(ObjectInputStream.java:422) at scala.collection.immutable.List$SerializationProxy.readObject(List.scala:479) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:1058) at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2136) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2027) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1535) at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:2245) at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2169) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2027) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1535) at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:2245) at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2169) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2027) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1535) at java.io.ObjectInputStream.readObject(ObjectInputStream.java:422) at scala.collection.immutable.List$SerializationProxy.readObject(List.scala:479) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:1058) at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2136) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2027) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1535) at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:2245) at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2169) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2027) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1535) at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:2245) at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2169) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2027) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1535) at java.io.ObjectInputStream.readObject(ObjectInputStream.java:422) at org.apache.spark.serializer.JavaDeserializationStream.readObject(JavaSerializer.scala:75) at org.apache.spark.serializer.JavaSerializerInstance.deserialize(JavaSerializer.scala:114) at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:80) at org.apache.spark.scheduler.Task.run(Task.scala:108) at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:335) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:748) Here is the some simple code. package app import org.apache.spark.sql.SparkSession import util.{ScalaSourceCodeCompiler} /** */ object Test { def main(args: Array[String]): Unit = { val spark = SparkSession .builder .appName("Test") .master("local") .getOrCreate() spark.sparkContext.getConf.setJars(Seq("/Users/dubin/code/java/BatchPro/BatchProSpark/target/BatchProSpark-1.0-SNAPSHOT.jar")) val logDataDF = spark.read.format("csv").option("header", "true").load("/Users/dubin/code/java/BatchPro/BatchProSpark/src/test/resources/cars.csv") logDataDF.show() logDataDF.registerTempTable("car") val code = """ |(a: String) => { a.toUpperCase } """.stripMargin val userUDF = ScalaSourceCodeCompiler.compileCodeTest(code) spark.udf.register("toU", userUDF) val res = spark.sql("select toU(t) from car") val r = res.toJSON.collect() res.printSchema() res.show() spark.stop() r.foreach(println(_)) } } and def compileCodeTest(code: String): String => String = { Eval[String=> String](code) } I already try some ways, I suspect the exception is related to the Eval run time, But I am not sure. Can anyone help? Thanks, Du Bin