diff --git a/core/src/main/scala/org/apache/spark/api/java/JavaRDDLike.scala b/core/src/main/scala/org/apache/spark/api/java/JavaRDDLike.scala index 1e9d4f1803..0e4d7dce0f 100644 --- a/core/src/main/scala/org/apache/spark/api/java/JavaRDDLike.scala +++ b/core/src/main/scala/org/apache/spark/api/java/JavaRDDLike.scala @@ -28,6 +28,7 @@ import com.google.common.base.Optional import org.apache.hadoop.io.compress.CompressionCodec import org.apache.spark._ +import org.apache.spark.annotation.Since import org.apache.spark.api.java.JavaPairRDD._ import org.apache.spark.api.java.JavaSparkContext.fakeClassTag import org.apache.spark.api.java.JavaUtils.mapAsSerializableJavaMap @@ -62,6 +63,10 @@ trait JavaRDDLike[T, This <: JavaRDDLike[T, This]] extends Serializable { /** Set of partitions in this RDD. */ def partitions: JList[Partition] = rdd.partitions.toSeq.asJava + /** Return the number of partitions in this RDD. */ + @Since("1.6.0") + def getNumPartitions: Int = rdd.getNumPartitions + /** The partitioner of this RDD. */ def partitioner: Optional[Partitioner] = JavaUtils.optionToOptional(rdd.partitioner) diff --git a/core/src/main/scala/org/apache/spark/rdd/RDD.scala b/core/src/main/scala/org/apache/spark/rdd/RDD.scala index 8b3731d935..9fe9d83a70 100644 --- a/core/src/main/scala/org/apache/spark/rdd/RDD.scala +++ b/core/src/main/scala/org/apache/spark/rdd/RDD.scala @@ -31,7 +31,7 @@ import org.apache.hadoop.mapred.TextOutputFormat import org.apache.spark._ import org.apache.spark.Partitioner._ -import org.apache.spark.annotation.DeveloperApi +import org.apache.spark.annotation.{Since, DeveloperApi} import org.apache.spark.api.java.JavaRDD import org.apache.spark.partial.BoundedDouble import org.apache.spark.partial.CountEvaluator @@ -242,6 +242,12 @@ abstract class RDD[T: ClassTag]( } } + /** + * Returns the number of partitions of this RDD. + */ + @Since("1.6.0") + final def getNumPartitions: Int = partitions.length + /** * Get the preferred locations of a partition, taking into account whether the * RDD is checkpointed. diff --git a/core/src/test/java/org/apache/spark/JavaAPISuite.java b/core/src/test/java/org/apache/spark/JavaAPISuite.java index 4d4e982050..11f1248c24 100644 --- a/core/src/test/java/org/apache/spark/JavaAPISuite.java +++ b/core/src/test/java/org/apache/spark/JavaAPISuite.java @@ -973,6 +973,19 @@ public class JavaAPISuite implements Serializable { Assert.assertEquals("[3, 7]", partitionSums.collect().toString()); } + @Test + public void getNumPartitions(){ + JavaRDD rdd1 = sc.parallelize(Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8), 3); + JavaDoubleRDD rdd2 = sc.parallelizeDoubles(Arrays.asList(1.0, 2.0, 3.0, 4.0), 2); + JavaPairRDD rdd3 = sc.parallelizePairs(Arrays.asList( + new Tuple2<>("a", 1), + new Tuple2<>("aa", 2), + new Tuple2<>("aaa", 3) + ), 2); + Assert.assertEquals(3, rdd1.getNumPartitions()); + Assert.assertEquals(2, rdd2.getNumPartitions()); + Assert.assertEquals(2, rdd3.getNumPartitions()); + } @Test public void repartition() { diff --git a/core/src/test/scala/org/apache/spark/rdd/RDDSuite.scala b/core/src/test/scala/org/apache/spark/rdd/RDDSuite.scala index 5f718ea9f7..46ed5c04f4 100644 --- a/core/src/test/scala/org/apache/spark/rdd/RDDSuite.scala +++ b/core/src/test/scala/org/apache/spark/rdd/RDDSuite.scala @@ -34,6 +34,7 @@ class RDDSuite extends SparkFunSuite with SharedSparkContext { test("basic operations") { val nums = sc.makeRDD(Array(1, 2, 3, 4), 2) + assert(nums.getNumPartitions === 2) assert(nums.collect().toList === List(1, 2, 3, 4)) assert(nums.toLocalIterator.toList === List(1, 2, 3, 4)) val dups = sc.makeRDD(Array(1, 1, 2, 2, 3, 3, 4, 4), 2) diff --git a/project/MimaExcludes.scala b/project/MimaExcludes.scala index 566bfe8efb..d3a3c0ceb6 100644 --- a/project/MimaExcludes.scala +++ b/project/MimaExcludes.scala @@ -155,6 +155,10 @@ object MimaExcludes { "org.apache.spark.storage.BlockManagerMessages$GetRpcHostPortForExecutor"), ProblemFilters.exclude[MissingClassProblem]( "org.apache.spark.storage.BlockManagerMessages$GetRpcHostPortForExecutor$") + ) ++ Seq( + // SPARK-3580 Add getNumPartitions method to JavaRDD + ProblemFilters.exclude[MissingMethodProblem]( + "org.apache.spark.api.java.JavaRDDLike.getNumPartitions") ) case v if v.startsWith("1.5") => Seq(