编辑：仍然没有修复，但我知道从密码返回的值导致错误：
[43.4171031,37.5049815,43.4171031,37.5049815]
它来自bbox作为空间查询：
val query = "call blah blah yield node return node.fromDate as fromDate, node.bbox as bbox ORDER BY node.toDateFormatLong DESC";
它不喜欢将node.bbox作为bbox返回，我必须把它拿出来让查询起作用。
如果我这样做，我会收回数据帧。如果我没有收到错误：
defined class DateLayerData
defined class ChangeScoreObj
changeScoreMap: java.util.Map[Integer,ChangeScoreObj] = {}
doCalculation: (lat1: BigDecimal, lon1: BigDecimal, lat2: BigDecimal, lon2: BigDecimal, radius: Double)Unit
main: (args: Array[String])Unit
MinLat: 34.6 minlon 40.9 maxlat: 34.7 maxlon: 41
java.lang.UnsupportedOperationException: empty collection
at org.apache.spark.rdd.RDD$$anonfun$first$1.apply(RDD.scala:1370)
at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:151)
at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:112)
at org.apache.spark.rdd.RDD.withScope(RDD.scala:362)
at org.apache.spark.rdd.RDD.first(RDD.scala:1367)
at org.neo4j.spark.Neo4j.loadDataFrame(Neo4j.scala:280)
at doCalculation(<console>:114)
at main(<console>:89)
... 81 elided
所以猜测我使用Option错了吗？
val initialDf2 = neo.cypher(query).loadDataFrame //this seems to fail on empty collection
initialDf2.take(1).headOption.map(_.getString(1)).foreach(println)
上面的这一行是在循环中运行的。 doCalculation函数的一部分，使用不同的值等一遍又一遍地调用。
尝试加载一次从NEO4j返回的数据帧在NEO4j中看起来像这样：
-1 “Detected” 1 20161104 3318 37.5049815 43.4171031 20161023 “filename.val” 9.2 "23OCT16" [43.4171031, 37.5049815, 43.4171031, 37.5049815]
所以我进行查询调用以获取看起来像上面一行的许多行之一：
try {
val initialDf2 = neo.cypher(query).loadDataFrame
val someVal = initialDf2.collectAsList()
val detectt = someVal.get(0).getString(1) //try to get the second field
println(detectt)
} catch {
case e: Exception => e.printStackTrace
}
我确实有一个try catch，因为有时发送给cypher的查询什么都不返回（我不知道如何处理它）
17/09/18 08:44:48 ERROR TaskSetManager: Task 0 in stage 298.0 failed 1 times; aborting job
org.apache.spark.SparkException: Job aborted due to stage failure: Task 0 in stage 298.0 failed 1 times, most recent failure: Lost task 0.0 in stage 298.0 (TID 298, localhost, executor driver): java.lang.RuntimeException: Error while encoding: java.lang.RuntimeException: java.util.Collections$UnmodifiableRandomAccessList is not a valid external type for schema of string
if (assertnotnull(input[0, org.apache.spark.sql.Row, true]).isNullAt) null else validateexternaltype(getexternalrowfield(assertnotnull(input[0, org.apache.spark.sql.Row, true]), 0, altitude), DoubleType) AS altitude#1678
if (assertnotnull(input[0, org.apache.spark.sql.Row, true]).isNullAt) null else staticinvoke(class org.apache.spark.unsafe.types.UTF8String, StringType, fromString, validateexternaltype(getexternalrowfield(assertnotnull(input[0, org.apache.spark.sql.Row, true]), 1, detect_type), StringType), true) AS detect_type#1679
if (assertnotnull(input[0, org.apache.spark.sql.Row, true]).isNullAt) null else validateexternaltype(getexternalrowfield(assertnotnull(input[0, org.apache.spark.sql.Row, true]), 2, gtype), LongType) AS gtype#1680L
if (assertnotnull(input[0, org.apache.spark.sql.Row, true]).isNullAt) null else validateexternaltype(getexternalrowfield(assertnotnull(input[0, org.apache.spark.sql.Row, true]), 3, toDateFormatLong), LongType) AS toDateFormatLong#1681L
if (assertnotnull(input[0, org.apache.spark.sql.Row, true]).isNullAt) null else validateexternaltype(getexternalrowfield(assertnotnull(input[0, org.apache.spark.sql.Row, true]), 4, change_area), LongType) AS change_area#1682L
if (assertnotnull(input[0, org.apache.spark.sql.Row, true]).isNullAt) null else validateexternaltype(getexternalrowfield(assertnotnull(input[0, org.apache.spark.sql.Row, true]), 5, latitude), DoubleType) AS latitude#1683
if (assertnotnull(input[0, org.apache.spark.sql.Row, true]).isNullAt) null else validateexternaltype(getexternalrowfield(assertnotnull(input[0, org.apache.spark.sql.Row, true]), 6, longitude), DoubleType) AS longitude#1684
if (assertnotnull(input[0, org.apache.spark.sql.Row, true]).isNullAt) null else validateexternaltype(getexternalrowfield(assertnotnull(input[0, org.apache.spark.sql.Row, true]), 7, fromDateFormatLong), LongType) AS fromDateFormatLong#1685L
if (assertnotnull(input[0, org.apache.spark.sql.Row, true]).isNullAt) null else staticinvoke(class org.apache.spark.unsafe.types.UTF8String, StringType, fromString, validateexternaltype(getexternalrowfield(assertnotnull(input[0, org.apache.spark.sql.Row, true]), 8, iids), StringType), true) AS iids#1686
if (assertnotnull(input[0, org.apache.spark.sql.Row, true]).isNullAt) null else validateexternaltype(getexternalrowfield(assertnotnull(input[0, org.apache.spark.sql.Row, true]), 9, detect_strength), DoubleType) AS detect_strength#1687
if (assertnotnull(input[0, org.apache.spark.sql.Row, true]).isNullAt) null else staticinvoke(class org.apache.spark.unsafe.types.UTF8String, StringType, fromString, validateexternaltype(getexternalrowfield(assertnotnull(input[0, org.apache.spark.sql.Row, true]), 10, fromDate), StringType), true) AS fromDate#1688
if (assertnotnull(input[0, org.apache.spark.sql.Row, true]).isNullAt) null else staticinvoke(class org.apache.spark.unsafe.types.UTF8String, StringType, fromString, validateexternaltype(getexternalrowfield(assertnotnull(input[0, org.apache.spark.sql.Row, true]), 11, bbox), StringType), true) AS bbox#1689
at org.apache.spark.sql.catalyst.encoders.ExpressionEncoder.toRow(ExpressionEncoder.scala:290)
at org.apache.spark.sql.SparkSession$$anonfun$3.apply(SparkSession.scala:573)