From 9234a1059806f639cf681c8ca5a038fb6a3c638d Mon Sep 17 00:00:00 2001 From: Scott Cowell Date: Mon, 18 Dec 2023 13:07:53 -0800 Subject: [PATCH] DX-85876: Failure in UnionReader.read after DecimalVector promotion to UnionVector When a DecimalVector is promoted to a UnionVector via a PromotableWriter, the UnionVector will have the decimal vector in it's internal struct vector, but the decimalVector field will not be set. If UnionReader.read is then used to read from the UnionVector, it will fail when it tries to read one of the promoted decimal values, due to decimalVector being null, and the exact decimal type not being provided. This failure is unnecessary though as we have a pre-existing decimal vector, the caller just does not know the exact type - and it shouldn't be required to. The change here is to check for a pre-existing decimal vector in the internal struct when getDecimalVector() is called. If one exists, set the decimalVector field and return. Otherwise, if none exists, throw the exception. --- .../main/codegen/templates/UnionVector.java | 6 ++- .../complex/impl/TestPromotableWriter.java | 45 +++++++++++++++++++ 2 files changed, 50 insertions(+), 1 deletion(-) diff --git a/java/vector/src/main/codegen/templates/UnionVector.java b/java/vector/src/main/codegen/templates/UnionVector.java index cf0ef06208d85..3b21a2bb9be4c 100644 --- a/java/vector/src/main/codegen/templates/UnionVector.java +++ b/java/vector/src/main/codegen/templates/UnionVector.java @@ -23,6 +23,7 @@ import org.apache.arrow.util.Preconditions; import org.apache.arrow.vector.BaseValueVector; import org.apache.arrow.vector.BitVectorHelper; +import org.apache.arrow.vector.DecimalVector; import org.apache.arrow.vector.FieldVector; import org.apache.arrow.vector.ValueVector; import org.apache.arrow.vector.complex.AbstractStructVector; @@ -293,7 +294,10 @@ public StructVector getStruct() { <#if minor.class?starts_with("Decimal")> public ${name}Vector get${name}Vector() { if (${uncappedName}Vector == null) { - throw new IllegalArgumentException("No ${uncappedName} present. Provide ArrowType argument to create a new vector"); + ${uncappedName}Vector = internalStruct.getChild(fieldName(MinorType.${name?upper_case}), ${name}Vector.class); + if (${uncappedName}Vector == null) { + throw new IllegalArgumentException("No ${uncappedName} present. Provide ArrowType argument to create a new vector"); + } } return ${uncappedName}Vector; } diff --git a/java/vector/src/test/java/org/apache/arrow/vector/complex/impl/TestPromotableWriter.java b/java/vector/src/test/java/org/apache/arrow/vector/complex/impl/TestPromotableWriter.java index 9dce33122e881..9ba5cc4cf91d9 100644 --- a/java/vector/src/test/java/org/apache/arrow/vector/complex/impl/TestPromotableWriter.java +++ b/java/vector/src/test/java/org/apache/arrow/vector/complex/impl/TestPromotableWriter.java @@ -21,17 +21,25 @@ import static org.junit.Assert.assertFalse; import static org.junit.Assert.assertNull; +import java.math.BigDecimal; + import org.apache.arrow.memory.BufferAllocator; +import org.apache.arrow.vector.DecimalVector; import org.apache.arrow.vector.DirtyRootAllocator; import org.apache.arrow.vector.complex.ListVector; import org.apache.arrow.vector.complex.NonNullableStructVector; import org.apache.arrow.vector.complex.StructVector; import org.apache.arrow.vector.complex.UnionVector; import org.apache.arrow.vector.complex.writer.BaseWriter.StructWriter; +import org.apache.arrow.vector.holders.NullableDecimalHolder; +import org.apache.arrow.vector.holders.NullableIntHolder; +import org.apache.arrow.vector.holders.UnionHolder; import org.apache.arrow.vector.types.Types; +import org.apache.arrow.vector.types.pojo.ArrowType; import org.apache.arrow.vector.types.pojo.ArrowType.ArrowTypeID; import org.apache.arrow.vector.types.pojo.Field; import org.apache.arrow.vector.types.pojo.FieldType; +import org.apache.arrow.vector.util.DecimalUtility; import org.junit.After; import org.junit.Before; import org.junit.Test; @@ -164,4 +172,41 @@ public void testNoPromoteToUnionWithNull() throws Exception { lv.close(); } } + + @Test + public void testPromoteToUnionFromDecimal() throws Exception { + try (final NonNullableStructVector container = NonNullableStructVector.empty(EMPTY_SCHEMA_PATH, allocator); + final DecimalVector v = container.addOrGet("dec", + FieldType.nullable(new ArrowType.Decimal(38, 1, 128)), DecimalVector.class); + final PromotableWriter writer = new PromotableWriter(v, container)) { + + container.allocateNew(); + container.setValueCount(1); + + writer.setPosition(0); + writer.writeDecimal(new BigDecimal("0.1")); + writer.setPosition(1); + writer.writeInt(1); + + container.setValueCount(3); + + UnionVector unionVector = (UnionVector) container.getChild("dec"); + UnionHolder holder = new UnionHolder(); + + unionVector.get(0, holder); + NullableDecimalHolder decimalHolder = new NullableDecimalHolder(); + holder.reader.read(decimalHolder); + + assertEquals(1, decimalHolder.isSet); + assertEquals(new BigDecimal("0.1"), + DecimalUtility.getBigDecimalFromArrowBuf(decimalHolder.buffer, 0, decimalHolder.scale, 128)); + + unionVector.get(1, holder); + NullableIntHolder intHolder = new NullableIntHolder(); + holder.reader.read(intHolder); + + assertEquals(1, intHolder.isSet); + assertEquals(1, intHolder.value); + } + } }