Make ScalaReflection be able to handle Generic case classes.

ueshin · ueshin · commit 7de570641d5b · 2014-06-26T15:36:26.000+09:00
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/ScalaReflection.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/ScalaReflection.scala
@@ -45,10 +45,15 @@ object ScalaReflection {
       val TypeRef(_, _, Seq(optType)) = t
       schemaFor(optType)
     case t if t <:< typeOf[Product] =>
-      val params = t.member("<init>": TermName).asMethod.paramss
+      val formalTypeArgs = t.typeSymbol.asClass.typeParams
+      val TypeRef(_, _, actualTypeArgs) = t
+      val params = t.member(nme.CONSTRUCTOR).asMethod.paramss
       StructType(
         params.head.map(p =>
-          StructField(p.name.toString, schemaFor(p.typeSignature), nullable = true)))
+          StructField(
+            p.name.toString,
+            schemaFor(p.typeSignature.substituteTypes(formalTypeArgs, actualTypeArgs)),
+            nullable = true)))
     // Need to decide if we actually need a special type here.
     case t if t <:< typeOf[Array[Byte]] => BinaryType
     case t if t <:< typeOf[Array[_]] =>
diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/ScalaReflectionSuite.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/ScalaReflectionSuite.scala
@@ -0,0 +1,46 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql.catalyst
+
+import java.sql.Timestamp
+
+import org.scalatest.FunSuite
+
+import org.apache.spark.sql.catalyst.expressions._
+import org.apache.spark.sql.catalyst.types._
+
+case class GenericData[A](
+    genericField: A)
+
+class ScalaReflectionSuite extends FunSuite {
+
+  test("generic data") {
+    val schema = ScalaReflection.schemaFor[GenericData[Int]]
+    assert(schema ===
+      StructType(Seq(
+        StructField("genericField", IntegerType, nullable = true))))
+  }
+
+  test("tuple data") {
+    val schema = ScalaReflection.schemaFor[(Int, String)]
+    assert(schema ===
+      StructType(Seq(
+        StructField("_1", IntegerType, nullable = true),
+        StructField("_2", StringType, nullable = true))))
+  }
+}
