Spark支持的java.time.Instant最大(小)值是多少（） Spark支持的java.time.Instant最大

java.time.Instant 在Spark 3.0中, java8 time API 被用到Spark datetime相关的内部计算和用户API中，比如Instant对象就被Mapping到Spark SQL类型TimestampType。TimestampType内部实际以Long表示microsecond, 如其文档所述：

/** * The timestamp type represents a time instant in microsecond precision. * Valid range is [0001-01-01T00:00:00.000000Z, 9999-12-31T23:59:59.999999Z] where * the left/right-bound is a date and time of the proleptic Gregorian * calendar in UTC+00:00. * * Please use the singleton `DataTypes.TimestampType` to refer the type. * @since 1.3.0 */

【Spark支持的java.time.Instant最大(小)值是多少（）】而Instant用一个Long类型字段存储EPOCH时刻相加减的秒数，和一个Int类型字段存储纳秒数，最大值和最小值远超Spark TimestampType所能承受的范围。

scala> Instant.MAX res22: java.time.Instant = +1000000000-12-31T23:59:59.999999999Z scala> Instant.MIN res25: java.time.Instant = -1000000000-01-01T00:00:00Z scala> Instant.EPOCH res26: java.time.Instant = 1970-01-01T00:00:00Z

那么Spark 能支持多大的Instant实例呢？

scala> val t = Instant.ofEpochSecond(9223372036854L, 775807999) t: java.time.Instant = +294247-01-10T04:00:54.775807999Zscala> Seq(t).toDF res20: org.apache.spark.sql.DataFrame = [value: timestamp]scala> val t = Instant.ofEpochSecond(9223372036854L, 775808000) t: java.time.Instant = +294247-01-10T04:00:54.775808Zscala> Seq(t).toDF java.lang.RuntimeException: Error while encoding: java.lang.ArithmeticException: long overflow staticinvoke(class org.apache.spark.sql.catalyst.util.DateTimeUtils$, TimestampType, instantToMicros, input[0, java.time.Instant, true], true, false) AS value#67 at org.apache.spark.sql.catalyst.encoders.ExpressionEncoder$Serializer.apply(ExpressionEncoder.scala:215) at org.apache.spark.sql.SparkSession.$anonfun$createDataset$1(SparkSession.scala:466) at scala.collection.TraversableLike.$anonfun$map$1(TraversableLike.scala:238) at scala.collection.immutable.List.foreach(List.scala:392) at scala.collection.TraversableLike.map(TraversableLike.scala:238) at scala.collection.TraversableLike.map$(TraversableLike.scala:231) at scala.collection.immutable.List.map(List.scala:298) at org.apache.spark.sql.SparkSession.createDataset(SparkSession.scala:466) at org.apache.spark.sql.SQLContext.createDataset(SQLContext.scala:353) at org.apache.spark.sql.SQLImplicits.localSeqToDatasetHolder(SQLImplicits.scala:231) ... 47 elided Caused by: java.lang.ArithmeticException: long overflow at java.lang.Math.addExact(Math.java:809) at org.apache.spark.sql.catalyst.util.DateTimeUtils$.instantToMicros(DateTimeUtils.scala:411) at org.apache.spark.sql.catalyst.util.DateTimeUtils.instantToMicros(DateTimeUtils.scala) at org.apache.spark.sql.catalyst.expressions.GeneratedClass$SpecificUnsafeProjection.apply(Unknown Source) at org.apache.spark.sql.catalyst.encoders.ExpressionEncoder$Serializer.apply(ExpressionEncoder.scala:211) ... 56 more

显然和Spark API文档描述的不一致，实际可以表示的Timestamp值最大为·+294247-01-10T04:00:54.775807999Z远比9999-12-31T23:59:59.999999Z`(文档值)大不少，也比Instant的实际最大值小了不少个数量级。
最小值雷同，不再赘述。