vector/src/main/codegen/templates/PromotableWriter.java - arrow-java - Git at Google

 /*
  * 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.
  */

 <@pp.dropOutputFile />
 <@pp.changeOutputFile name="/org/apache/arrow/vector/complex/impl/PromotableWriter.java" />

 <#include "/@includes/license.ftl" />

 package org.apache.arrow.vector.complex.impl;

 import java.util.Locale;
 <#include "/@includes/vv_imports.ftl" />

 /**
  * This FieldWriter implementation delegates all FieldWriter API calls to an inner FieldWriter. This
  * inner field writer can start as a specific type, and this class will promote the writer to a
  * UnionWriter if a call is made that the specifically typed writer cannot handle. A new UnionVector
  * is created, wrapping the original vector, and replaces the original vector in the parent vector,
  * which can be either an AbstractStructVector or a ListVector.
  *
  * <p>The writer used can either be for single elements (struct) or lists.
  */
 public class PromotableWriter extends AbstractPromotableFieldWriter {

   protected final AbstractStructVector parentContainer;
   protected final ListVector listVector;
   protected final ListViewVector listViewVector;
   protected final FixedSizeListVector fixedListVector;
   protected final LargeListVector largeListVector;
   protected final LargeListViewVector largeListViewVector;
   protected final NullableStructWriterFactory nullableStructWriterFactory;
   protected int position;
   protected static final int MAX_DECIMAL_PRECISION = 38;
   protected static final int MAX_DECIMAL256_PRECISION = 76;

   protected enum State {
     UNTYPED,
     SINGLE,
     UNION
   }

   protected MinorType type;
   protected ValueVector vector;
   protected UnionVector unionVector;
   protected State state;
   protected FieldWriter writer;

   /**
    * Constructs a new instance.
    *
    * @param v The vector to write.
    * @param parentContainer The parent container for the vector.
    */
   public PromotableWriter(ValueVector v, AbstractStructVector parentContainer) {
     this(v, parentContainer, NullableStructWriterFactory.getNullableStructWriterFactoryInstance());
   }

   /**
    * Constructs a new instance.
    *
    * @param v The vector to initialize the writer with.
    * @param parentContainer The parent container for the vector.
    * @param nullableStructWriterFactory The factory to create the delegate writer.
    */
   public PromotableWriter(
       ValueVector v,
       AbstractStructVector parentContainer,
       NullableStructWriterFactory nullableStructWriterFactory) {
     this.parentContainer = parentContainer;
     this.listVector = null;
     this.listViewVector = null;
     this.fixedListVector = null;
     this.largeListVector = null;
     this.largeListViewVector = null;
     this.nullableStructWriterFactory = nullableStructWriterFactory;
     init(v);
   }

   /**
    * Constructs a new instance.
    *
    * @param v The vector to initialize the writer with.
    * @param listVector The vector that serves as a parent of v.
    */
   public PromotableWriter(ValueVector v, ListVector listVector) {
     this(v, listVector, NullableStructWriterFactory.getNullableStructWriterFactoryInstance());
   }

   /**
    * Constructs a new instance.
    *
    * @param v The vector to initialize the writer with.
    * @param fixedListVector The vector that serves as a parent of v.
    */
   public PromotableWriter(ValueVector v, FixedSizeListVector fixedListVector) {
     this(v, fixedListVector, NullableStructWriterFactory.getNullableStructWriterFactoryInstance());
   }

   /**
    * Constructs a new instance.
    *
    * @param v The vector to initialize the writer with.
    * @param largeListVector The vector that serves as a parent of v.
    */
   public PromotableWriter(ValueVector v, LargeListVector largeListVector) {
     this(v, largeListVector, NullableStructWriterFactory.getNullableStructWriterFactoryInstance());
   }

   /**
    * Constructs a new instance.
    *
    * @param v The vector to initialize the writer with.
    * @param listViewVector The vector that serves as a parent of v.
    */
   public PromotableWriter(ValueVector v, ListViewVector listViewVector) {
     this(v, listViewVector, NullableStructWriterFactory.getNullableStructWriterFactoryInstance());
   }

   /**
    * Constructs a new instance.
    *
    * @param v The vector to initialize the writer with.
    * @param largeListViewVector The vector that serves as a parent of v.
    */
   public PromotableWriter(ValueVector v, LargeListViewVector largeListViewVector) {
     this(v, largeListViewVector, NullableStructWriterFactory.getNullableStructWriterFactoryInstance());
   }

   /**
    * Constructs a new instance.
    *
    * @param v The vector to initialize the writer with.
    * @param listVector The vector that serves as a parent of v.
    * @param nullableStructWriterFactory The factory to create the delegate writer.
    */
   public PromotableWriter(
       ValueVector v,
       ListVector listVector,
       NullableStructWriterFactory nullableStructWriterFactory) {
     this.listVector = listVector;
     this.listViewVector = null;
     this.parentContainer = null;
     this.fixedListVector = null;
     this.largeListVector = null;
     this.largeListViewVector = null;
     this.nullableStructWriterFactory = nullableStructWriterFactory;
     init(v);
   }

   /**
    * Constructs a new instance.
    *
    * @param v The vector to initialize the writer with.
    * @param listViewVector The vector that serves as a parent of v.
    * @param nullableStructWriterFactory The factory to create the delegate writer.
    */
   public PromotableWriter(
       ValueVector v,
       ListViewVector listViewVector,
       NullableStructWriterFactory nullableStructWriterFactory) {
     this.listViewVector = listViewVector;
     this.listVector = null;
     this.parentContainer = null;
     this.fixedListVector = null;
     this.largeListVector = null;
     this.largeListViewVector = null;
     this.nullableStructWriterFactory = nullableStructWriterFactory;
     init(v);
   }

   /**
    * Constructs a new instance.
    *
    * @param v The vector to initialize the writer with.
    * @param fixedListVector The vector that serves as a parent of v.
    * @param nullableStructWriterFactory The factory to create the delegate writer.
    */
   public PromotableWriter(
       ValueVector v,
       FixedSizeListVector fixedListVector,
       NullableStructWriterFactory nullableStructWriterFactory) {
     this.fixedListVector = fixedListVector;
     this.parentContainer = null;
     this.listVector = null;
     this.listViewVector = null;
     this.largeListVector = null;
     this.largeListViewVector = null;
     this.nullableStructWriterFactory = nullableStructWriterFactory;
     init(v);
   }

   /**
    * Constructs a new instance.
    *
    * @param v The vector to initialize the writer with.
    * @param largeListVector The vector that serves as a parent of v.
    * @param nullableStructWriterFactory The factory to create the delegate writer.
    */
   public PromotableWriter(
       ValueVector v,
       LargeListVector largeListVector,
       NullableStructWriterFactory nullableStructWriterFactory) {
     this.largeListVector = largeListVector;
     this.fixedListVector = null;
     this.parentContainer = null;
     this.listVector = null;
     this.listViewVector = null;
     this.largeListViewVector = null;
     this.nullableStructWriterFactory = nullableStructWriterFactory;
     init(v);
   }

   /**
    * Constructs a new instance.
    *
    * @param v The vector to initialize the writer with.
    * @param largeListViewVector The vector that serves as a parent of v.
    * @param nullableStructWriterFactory The factory to create the delegate writer.
    */
   public PromotableWriter(
       ValueVector v,
       LargeListViewVector largeListViewVector,
       NullableStructWriterFactory nullableStructWriterFactory) {
     this.largeListViewVector = largeListViewVector;
     this.fixedListVector = null;
     this.parentContainer = null;
     this.listVector = null;
     this.listViewVector = null;
     this.largeListVector = null;
     this.nullableStructWriterFactory = nullableStructWriterFactory;
     init(v);
   }

   private void init(ValueVector v) {
     if (v instanceof UnionVector) {
       state = State.UNION;
       unionVector = (UnionVector) v;
       writer = new UnionWriter(unionVector, nullableStructWriterFactory);
     } else if (v instanceof NullVector) {
       state = State.UNTYPED;
     } else {
       setWriter(v);
     }
   }

   @Override
   public void setAddVectorAsNullable(boolean nullable) {
     super.setAddVectorAsNullable(nullable);
     if (writer instanceof AbstractFieldWriter) {
       ((AbstractFieldWriter) writer).setAddVectorAsNullable(nullable);
     }
   }

   protected void setWriter(ValueVector v) {
     state = State.SINGLE;
     vector = v;
     type = v.getMinorType();
     switch (type) {
       case STRUCT:
         writer = nullableStructWriterFactory.build((StructVector) vector);
         break;
       case LIST:
         writer = new UnionListWriter((ListVector) vector, nullableStructWriterFactory);
         break;
       case LISTVIEW:
         writer = new UnionListViewWriter((ListViewVector) vector, nullableStructWriterFactory);
         break;
       case MAP:
         writer = new UnionMapWriter((MapVector) vector);
         break;
       case UNION:
         writer = new UnionWriter((UnionVector) vector, nullableStructWriterFactory);
         break;
       case EXTENSIONTYPE:
         writer = new UnionExtensionWriter((ExtensionTypeVector) vector);
         break;
       default:
         writer = type.getNewFieldWriter(vector);
         break;
     }
   }

   @Override
   public void writeNull() {
     FieldWriter w = getWriter();
     if (w != null) {
       w.writeNull();
     }
     setPosition(idx() + 1);
   }

   @Override
   public void setPosition(int index) {
     super.setPosition(index);
     FieldWriter w = getWriter();
     if (w == null) {
       position = index;
     } else {
       w.setPosition(index);
     }
   }

   protected boolean requiresArrowType(MinorType type) {
     return type == MinorType.DECIMAL
         || type == MinorType.MAP
         || type == MinorType.DURATION
         || type == MinorType.FIXEDSIZEBINARY
         || type == MinorType.EXTENSIONTYPE
         || (type.name().startsWith("TIMESTAMP") && type.name().endsWith("TZ"));
   }

   @Override
   protected FieldWriter getWriter(MinorType type, ArrowType arrowType) {
     if (state == State.UNION) {
       if (requiresArrowType(type)) {
         ((UnionWriter) writer).getWriter(type, arrowType);
       } else {
         ((UnionWriter) writer).getWriter(type);
       }
     } else if (state == State.UNTYPED) {
       if (type == null) {
         // ???
         return null;
       }
       if (arrowType == null) {
         arrowType = type.getType();
       }
       FieldType fieldType = new FieldType(addVectorAsNullable, arrowType, null, null);
       ValueVector v;
       if (listVector != null) {
         v = listVector.addOrGetVector(fieldType).getVector();
       } else if (fixedListVector != null) {
         v = fixedListVector.addOrGetVector(fieldType).getVector();
       } else if (listViewVector != null) {
         v = listViewVector.addOrGetVector(fieldType).getVector();
       } else {
         v = largeListVector.addOrGetVector(fieldType).getVector();
       }
       v.allocateNew();
       setWriter(v);
       writer.setPosition(position);
     } else if (type != this.type) {
       promoteToUnion();
       if (requiresArrowType(type)) {
         ((UnionWriter) writer).getWriter(type, arrowType);
       } else {
         ((UnionWriter) writer).getWriter(type);
       }
     }
     return writer;
   }

   @Override
   public boolean isEmptyStruct() {
     return writer.isEmptyStruct();
   }

   @Override
   protected FieldWriter getWriter() {
     return writer;
   }

   protected FieldWriter promoteToUnion() {
     String name = vector.getField().getName();
     TransferPair tp =
         vector.getTransferPair(
             vector.getMinorType().name().toLowerCase(Locale.ROOT), vector.getAllocator());
     tp.transfer();
     if (parentContainer != null) {
       // TODO allow dictionaries in complex types
       unionVector = parentContainer.addOrGetUnion(name);
       unionVector.allocateNew();
     } else if (listVector != null) {
       unionVector = listVector.promoteToUnion();
     } else if (fixedListVector != null) {
       unionVector = fixedListVector.promoteToUnion();
     } else if (largeListVector != null) {
       unionVector = largeListVector.promoteToUnion();
     } else if (listViewVector != null) {
       unionVector = listViewVector.promoteToUnion();
     }
     unionVector.addVector((FieldVector) tp.getTo());
     writer = new UnionWriter(unionVector, nullableStructWriterFactory);
     writer.setPosition(idx());
     for (int i = 0; i <= idx(); i++) {
       unionVector.setType(i, vector.getMinorType());
     }
     vector = null;
     state = State.UNION;
     return writer;
   }

   @Override
   public void write(DecimalHolder holder) {
     getWriter(
         MinorType.DECIMAL,
         new ArrowType.Decimal(MAX_DECIMAL_PRECISION, holder.scale, /*bitWidth=*/ 128))
         .write(holder);
   }

   @Override
   public void writeDecimal(long start, ArrowBuf buffer, ArrowType arrowType) {
     getWriter(
         MinorType.DECIMAL,
         new ArrowType.Decimal(
             MAX_DECIMAL_PRECISION,
             ((ArrowType.Decimal) arrowType).getScale(),
             /*bitWidth=*/ 128))
         .writeDecimal(start, buffer, arrowType);
   }

   @Override
   public void writeDecimal(BigDecimal value) {
     getWriter(
         MinorType.DECIMAL,
         new ArrowType.Decimal(MAX_DECIMAL_PRECISION, value.scale(), /*bitWidth=*/ 128))
         .writeDecimal(value);
   }

   @Override
   public void writeBigEndianBytesToDecimal(byte[] value, ArrowType arrowType) {
     getWriter(
         MinorType.DECIMAL,
         new ArrowType.Decimal(
             MAX_DECIMAL_PRECISION,
             ((ArrowType.Decimal) arrowType).getScale(),
             /*bitWidth=*/ 128))
         .writeBigEndianBytesToDecimal(value, arrowType);
   }

   @Override
   public void write(Decimal256Holder holder) {
     getWriter(
         MinorType.DECIMAL256,
         new ArrowType.Decimal(MAX_DECIMAL256_PRECISION, holder.scale, /*bitWidth=*/ 256))
         .write(holder);
   }

   @Override
   public void writeDecimal256(long start, ArrowBuf buffer, ArrowType arrowType) {
     getWriter(
         MinorType.DECIMAL256,
         new ArrowType.Decimal(
             MAX_DECIMAL256_PRECISION,
             ((ArrowType.Decimal) arrowType).getScale(),
             /*bitWidth=*/ 256))
         .writeDecimal256(start, buffer, arrowType);
   }

   @Override
   public void writeDecimal256(BigDecimal value) {
     getWriter(
         MinorType.DECIMAL256,
         new ArrowType.Decimal(MAX_DECIMAL256_PRECISION, value.scale(), /*bitWidth=*/ 256))
         .writeDecimal256(value);
   }

   @Override
   public void writeBigEndianBytesToDecimal256(byte[] value, ArrowType arrowType) {
     getWriter(
         MinorType.DECIMAL256,
         new ArrowType.Decimal(
             MAX_DECIMAL256_PRECISION,
             ((ArrowType.Decimal) arrowType).getScale(),
             /*bitWidth=*/ 256))
         .writeBigEndianBytesToDecimal256(value, arrowType);
   }

   @Override
   public void writeVarBinary(byte[] value) {
     getWriter(MinorType.VARBINARY).writeVarBinary(value);
   }

   @Override
   public void writeVarBinary(byte[] value, int offset, int length) {
     getWriter(MinorType.VARBINARY).writeVarBinary(value, offset, length);
   }

   @Override
   public void writeVarBinary(ByteBuffer value) {
     getWriter(MinorType.VARBINARY).writeVarBinary(value);
   }

   @Override
   public void writeVarBinary(ByteBuffer value, int offset, int length) {
     getWriter(MinorType.VARBINARY).writeVarBinary(value, offset, length);
   }

   @Override
   public void writeLargeVarBinary(byte[] value) {
     getWriter(MinorType.LARGEVARBINARY).writeLargeVarBinary(value);
   }

   @Override
   public void writeLargeVarBinary(byte[] value, int offset, int length) {
     getWriter(MinorType.LARGEVARBINARY).writeLargeVarBinary(value, offset, length);
   }

   @Override
   public void writeLargeVarBinary(ByteBuffer value) {
     getWriter(MinorType.LARGEVARBINARY).writeLargeVarBinary(value);
   }

   @Override
   public void writeLargeVarBinary(ByteBuffer value, int offset, int length) {
     getWriter(MinorType.LARGEVARBINARY).writeLargeVarBinary(value, offset, length);
   }

   @Override
   public void writeVarChar(Text value) {
     getWriter(MinorType.VARCHAR).writeVarChar(value);
   }

   @Override
   public void writeVarChar(String value) {
     getWriter(MinorType.VARCHAR).writeVarChar(value);
   }

   @Override
   public void writeLargeVarChar(Text value) {
     getWriter(MinorType.LARGEVARCHAR).writeLargeVarChar(value);
   }

   @Override
   public void writeLargeVarChar(String value) {
     getWriter(MinorType.LARGEVARCHAR).writeLargeVarChar(value);
   }

   @Override
   public void writeExtension(Object value) {
     getWriter(MinorType.EXTENSIONTYPE).writeExtension(value);
   }

   @Override
   public void addExtensionTypeWriterFactory(ExtensionTypeWriterFactory factory) {
     getWriter(MinorType.EXTENSIONTYPE).addExtensionTypeWriterFactory(factory);
   }

   public void addExtensionTypeWriterFactory(ExtensionTypeWriterFactory factory, ArrowType arrowType) {
     getWriter(MinorType.EXTENSIONTYPE, arrowType).addExtensionTypeWriterFactory(factory);
   }

   @Override
   public void allocate() {
     getWriter().allocate();
   }

   @Override
   public void clear() {
     getWriter().clear();
   }

   @Override
   public Field getField() {
     return getWriter().getField();
   }

   @Override
   public int getValueCapacity() {
     return getWriter().getValueCapacity();
   }

   @Override
   public void close() throws Exception {
     getWriter().close();
   }

   /**
    * Convert the writer to a PromotableViewWriter.
    *
    * @return The writer as a PromotableViewWriter.
    */
   public PromotableViewWriter toViewWriter() {
     PromotableViewWriter promotableViewWriter = new PromotableViewWriter(unionVector, parentContainer, nullableStructWriterFactory);
     promotableViewWriter.position = position;
     promotableViewWriter.writer = writer;
     promotableViewWriter.state = state;
     promotableViewWriter.unionVector = unionVector;
     promotableViewWriter.type = MinorType.LISTVIEW;
     return promotableViewWriter;
   }
 }
	/*
	* 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.
	*/

	<@pp.dropOutputFile />
	<@pp.changeOutputFile name="/org/apache/arrow/vector/complex/impl/PromotableWriter.java" />

	<#include "/@includes/license.ftl" />

	package org.apache.arrow.vector.complex.impl;

	import java.util.Locale;
	<#include "/@includes/vv_imports.ftl" />

	/**
	* This FieldWriter implementation delegates all FieldWriter API calls to an inner FieldWriter. This
	* inner field writer can start as a specific type, and this class will promote the writer to a
	* UnionWriter if a call is made that the specifically typed writer cannot handle. A new UnionVector
	* is created, wrapping the original vector, and replaces the original vector in the parent vector,
	* which can be either an AbstractStructVector or a ListVector.
	*
	* <p>The writer used can either be for single elements (struct) or lists.
	*/
	public class PromotableWriter extends AbstractPromotableFieldWriter {

	protected final AbstractStructVector parentContainer;
	protected final ListVector listVector;
	protected final ListViewVector listViewVector;
	protected final FixedSizeListVector fixedListVector;
	protected final LargeListVector largeListVector;
	protected final LargeListViewVector largeListViewVector;
	protected final NullableStructWriterFactory nullableStructWriterFactory;
	protected int position;
	protected static final int MAX_DECIMAL_PRECISION = 38;
	protected static final int MAX_DECIMAL256_PRECISION = 76;

	protected enum State {
	UNTYPED,
	SINGLE,
	UNION
	}

	protected MinorType type;
	protected ValueVector vector;
	protected UnionVector unionVector;
	protected State state;
	protected FieldWriter writer;

	/**
	* Constructs a new instance.
	*
	* @param v The vector to write.
	* @param parentContainer The parent container for the vector.
	*/
	public PromotableWriter(ValueVector v, AbstractStructVector parentContainer) {
	this(v, parentContainer, NullableStructWriterFactory.getNullableStructWriterFactoryInstance());
	}

	/**
	* Constructs a new instance.
	*
	* @param v The vector to initialize the writer with.
	* @param parentContainer The parent container for the vector.
	* @param nullableStructWriterFactory The factory to create the delegate writer.
	*/
	public PromotableWriter(
	ValueVector v,
	AbstractStructVector parentContainer,
	NullableStructWriterFactory nullableStructWriterFactory) {
	this.parentContainer = parentContainer;
	this.listVector = null;
	this.listViewVector = null;
	this.fixedListVector = null;
	this.largeListVector = null;
	this.largeListViewVector = null;
	this.nullableStructWriterFactory = nullableStructWriterFactory;
	init(v);
	}

	/**
	* Constructs a new instance.
	*
	* @param v The vector to initialize the writer with.
	* @param listVector The vector that serves as a parent of v.
	*/
	public PromotableWriter(ValueVector v, ListVector listVector) {
	this(v, listVector, NullableStructWriterFactory.getNullableStructWriterFactoryInstance());
	}

	/**
	* Constructs a new instance.
	*
	* @param v The vector to initialize the writer with.
	* @param fixedListVector The vector that serves as a parent of v.
	*/
	public PromotableWriter(ValueVector v, FixedSizeListVector fixedListVector) {
	this(v, fixedListVector, NullableStructWriterFactory.getNullableStructWriterFactoryInstance());
	}

	/**
	* Constructs a new instance.
	*
	* @param v The vector to initialize the writer with.
	* @param largeListVector The vector that serves as a parent of v.
	*/
	public PromotableWriter(ValueVector v, LargeListVector largeListVector) {
	this(v, largeListVector, NullableStructWriterFactory.getNullableStructWriterFactoryInstance());
	}

	/**
	* Constructs a new instance.
	*
	* @param v The vector to initialize the writer with.
	* @param listViewVector The vector that serves as a parent of v.
	*/
	public PromotableWriter(ValueVector v, ListViewVector listViewVector) {
	this(v, listViewVector, NullableStructWriterFactory.getNullableStructWriterFactoryInstance());
	}

	/**
	* Constructs a new instance.
	*
	* @param v The vector to initialize the writer with.
	* @param largeListViewVector The vector that serves as a parent of v.
	*/
	public PromotableWriter(ValueVector v, LargeListViewVector largeListViewVector) {
	this(v, largeListViewVector, NullableStructWriterFactory.getNullableStructWriterFactoryInstance());
	}

	/**
	* Constructs a new instance.
	*
	* @param v The vector to initialize the writer with.
	* @param listVector The vector that serves as a parent of v.
	* @param nullableStructWriterFactory The factory to create the delegate writer.
	*/
	public PromotableWriter(
	ValueVector v,
	ListVector listVector,
	NullableStructWriterFactory nullableStructWriterFactory) {
	this.listVector = listVector;
	this.listViewVector = null;
	this.parentContainer = null;
	this.fixedListVector = null;
	this.largeListVector = null;
	this.largeListViewVector = null;
	this.nullableStructWriterFactory = nullableStructWriterFactory;
	init(v);
	}

	/**
	* Constructs a new instance.
	*
	* @param v The vector to initialize the writer with.
	* @param listViewVector The vector that serves as a parent of v.
	* @param nullableStructWriterFactory The factory to create the delegate writer.
	*/
	public PromotableWriter(
	ValueVector v,
	ListViewVector listViewVector,
	NullableStructWriterFactory nullableStructWriterFactory) {
	this.listViewVector = listViewVector;
	this.listVector = null;
	this.parentContainer = null;
	this.fixedListVector = null;
	this.largeListVector = null;
	this.largeListViewVector = null;
	this.nullableStructWriterFactory = nullableStructWriterFactory;
	init(v);
	}

	/**
	* Constructs a new instance.
	*
	* @param v The vector to initialize the writer with.
	* @param fixedListVector The vector that serves as a parent of v.
	* @param nullableStructWriterFactory The factory to create the delegate writer.
	*/
	public PromotableWriter(
	ValueVector v,
	FixedSizeListVector fixedListVector,
	NullableStructWriterFactory nullableStructWriterFactory) {
	this.fixedListVector = fixedListVector;
	this.parentContainer = null;
	this.listVector = null;
	this.listViewVector = null;
	this.largeListVector = null;
	this.largeListViewVector = null;
	this.nullableStructWriterFactory = nullableStructWriterFactory;
	init(v);
	}

	/**
	* Constructs a new instance.
	*
	* @param v The vector to initialize the writer with.
	* @param largeListVector The vector that serves as a parent of v.
	* @param nullableStructWriterFactory The factory to create the delegate writer.
	*/
	public PromotableWriter(
	ValueVector v,
	LargeListVector largeListVector,
	NullableStructWriterFactory nullableStructWriterFactory) {
	this.largeListVector = largeListVector;
	this.fixedListVector = null;
	this.parentContainer = null;
	this.listVector = null;
	this.listViewVector = null;
	this.largeListViewVector = null;
	this.nullableStructWriterFactory = nullableStructWriterFactory;
	init(v);
	}

	/**
	* Constructs a new instance.
	*
	* @param v The vector to initialize the writer with.
	* @param largeListViewVector The vector that serves as a parent of v.
	* @param nullableStructWriterFactory The factory to create the delegate writer.
	*/
	public PromotableWriter(
	ValueVector v,
	LargeListViewVector largeListViewVector,
	NullableStructWriterFactory nullableStructWriterFactory) {
	this.largeListViewVector = largeListViewVector;
	this.fixedListVector = null;
	this.parentContainer = null;
	this.listVector = null;
	this.listViewVector = null;
	this.largeListVector = null;
	this.nullableStructWriterFactory = nullableStructWriterFactory;
	init(v);
	}

	private void init(ValueVector v) {
	if (v instanceof UnionVector) {
	state = State.UNION;
	unionVector = (UnionVector) v;
	writer = new UnionWriter(unionVector, nullableStructWriterFactory);
	} else if (v instanceof NullVector) {
	state = State.UNTYPED;
	} else {
	setWriter(v);
	}
	}

	@Override
	public void setAddVectorAsNullable(boolean nullable) {
	super.setAddVectorAsNullable(nullable);
	if (writer instanceof AbstractFieldWriter) {
	((AbstractFieldWriter) writer).setAddVectorAsNullable(nullable);
	}
	}

	protected void setWriter(ValueVector v) {
	state = State.SINGLE;
	vector = v;
	type = v.getMinorType();
	switch (type) {
	case STRUCT:
	writer = nullableStructWriterFactory.build((StructVector) vector);
	break;
	case LIST:
	writer = new UnionListWriter((ListVector) vector, nullableStructWriterFactory);
	break;
	case LISTVIEW:
	writer = new UnionListViewWriter((ListViewVector) vector, nullableStructWriterFactory);
	break;
	case MAP:
	writer = new UnionMapWriter((MapVector) vector);
	break;
	case UNION:
	writer = new UnionWriter((UnionVector) vector, nullableStructWriterFactory);
	break;
	case EXTENSIONTYPE:
	writer = new UnionExtensionWriter((ExtensionTypeVector) vector);
	break;
	default:
	writer = type.getNewFieldWriter(vector);
	break;
	}
	}

	@Override
	public void writeNull() {
	FieldWriter w = getWriter();
	if (w != null) {
	w.writeNull();
	}
	setPosition(idx() + 1);
	}

	@Override
	public void setPosition(int index) {
	super.setPosition(index);
	FieldWriter w = getWriter();
	if (w == null) {
	position = index;
	} else {
	w.setPosition(index);
	}
	}

	protected boolean requiresArrowType(MinorType type) {
	return type == MinorType.DECIMAL
	\|\| type == MinorType.MAP
	\|\| type == MinorType.DURATION
	\|\| type == MinorType.FIXEDSIZEBINARY
	\|\| type == MinorType.EXTENSIONTYPE
	\|\| (type.name().startsWith("TIMESTAMP") && type.name().endsWith("TZ"));
	}

	@Override
	protected FieldWriter getWriter(MinorType type, ArrowType arrowType) {
	if (state == State.UNION) {
	if (requiresArrowType(type)) {
	((UnionWriter) writer).getWriter(type, arrowType);
	} else {
	((UnionWriter) writer).getWriter(type);
	}
	} else if (state == State.UNTYPED) {
	if (type == null) {
	// ???
	return null;
	}
	if (arrowType == null) {
	arrowType = type.getType();
	}
	FieldType fieldType = new FieldType(addVectorAsNullable, arrowType, null, null);
	ValueVector v;
	if (listVector != null) {
	v = listVector.addOrGetVector(fieldType).getVector();
	} else if (fixedListVector != null) {
	v = fixedListVector.addOrGetVector(fieldType).getVector();
	} else if (listViewVector != null) {
	v = listViewVector.addOrGetVector(fieldType).getVector();
	} else {
	v = largeListVector.addOrGetVector(fieldType).getVector();
	}
	v.allocateNew();
	setWriter(v);
	writer.setPosition(position);
	} else if (type != this.type) {
	promoteToUnion();
	if (requiresArrowType(type)) {
	((UnionWriter) writer).getWriter(type, arrowType);
	} else {
	((UnionWriter) writer).getWriter(type);
	}
	}
	return writer;
	}

	@Override
	public boolean isEmptyStruct() {
	return writer.isEmptyStruct();
	}

	@Override
	protected FieldWriter getWriter() {
	return writer;
	}

	protected FieldWriter promoteToUnion() {
	String name = vector.getField().getName();
	TransferPair tp =
	vector.getTransferPair(
	vector.getMinorType().name().toLowerCase(Locale.ROOT), vector.getAllocator());
	tp.transfer();
	if (parentContainer != null) {
	// TODO allow dictionaries in complex types
	unionVector = parentContainer.addOrGetUnion(name);
	unionVector.allocateNew();
	} else if (listVector != null) {
	unionVector = listVector.promoteToUnion();
	} else if (fixedListVector != null) {
	unionVector = fixedListVector.promoteToUnion();
	} else if (largeListVector != null) {
	unionVector = largeListVector.promoteToUnion();
	} else if (listViewVector != null) {
	unionVector = listViewVector.promoteToUnion();
	}
	unionVector.addVector((FieldVector) tp.getTo());
	writer = new UnionWriter(unionVector, nullableStructWriterFactory);
	writer.setPosition(idx());
	for (int i = 0; i <= idx(); i++) {
	unionVector.setType(i, vector.getMinorType());
	}
	vector = null;
	state = State.UNION;
	return writer;
	}

	@Override
	public void write(DecimalHolder holder) {
	getWriter(
	MinorType.DECIMAL,
	new ArrowType.Decimal(MAX_DECIMAL_PRECISION, holder.scale, /bitWidth=/ 128))
	.write(holder);
	}

	@Override
	public void writeDecimal(long start, ArrowBuf buffer, ArrowType arrowType) {
	getWriter(
	MinorType.DECIMAL,
	new ArrowType.Decimal(
	MAX_DECIMAL_PRECISION,
	((ArrowType.Decimal) arrowType).getScale(),
	/bitWidth=/ 128))
	.writeDecimal(start, buffer, arrowType);
	}

	@Override
	public void writeDecimal(BigDecimal value) {
	getWriter(
	MinorType.DECIMAL,
	new ArrowType.Decimal(MAX_DECIMAL_PRECISION, value.scale(), /bitWidth=/ 128))
	.writeDecimal(value);
	}

	@Override
	public void writeBigEndianBytesToDecimal(byte[] value, ArrowType arrowType) {
	getWriter(
	MinorType.DECIMAL,
	new ArrowType.Decimal(
	MAX_DECIMAL_PRECISION,
	((ArrowType.Decimal) arrowType).getScale(),
	/bitWidth=/ 128))
	.writeBigEndianBytesToDecimal(value, arrowType);
	}

	@Override
	public void write(Decimal256Holder holder) {
	getWriter(
	MinorType.DECIMAL256,
	new ArrowType.Decimal(MAX_DECIMAL256_PRECISION, holder.scale, /bitWidth=/ 256))
	.write(holder);
	}

	@Override
	public void writeDecimal256(long start, ArrowBuf buffer, ArrowType arrowType) {
	getWriter(
	MinorType.DECIMAL256,
	new ArrowType.Decimal(
	MAX_DECIMAL256_PRECISION,
	((ArrowType.Decimal) arrowType).getScale(),
	/bitWidth=/ 256))
	.writeDecimal256(start, buffer, arrowType);
	}

	@Override
	public void writeDecimal256(BigDecimal value) {
	getWriter(
	MinorType.DECIMAL256,
	new ArrowType.Decimal(MAX_DECIMAL256_PRECISION, value.scale(), /bitWidth=/ 256))
	.writeDecimal256(value);
	}

	@Override
	public void writeBigEndianBytesToDecimal256(byte[] value, ArrowType arrowType) {
	getWriter(
	MinorType.DECIMAL256,
	new ArrowType.Decimal(
	MAX_DECIMAL256_PRECISION,
	((ArrowType.Decimal) arrowType).getScale(),
	/bitWidth=/ 256))
	.writeBigEndianBytesToDecimal256(value, arrowType);
	}

	@Override
	public void writeVarBinary(byte[] value) {
	getWriter(MinorType.VARBINARY).writeVarBinary(value);
	}

	@Override
	public void writeVarBinary(byte[] value, int offset, int length) {
	getWriter(MinorType.VARBINARY).writeVarBinary(value, offset, length);
	}

	@Override
	public void writeVarBinary(ByteBuffer value) {
	getWriter(MinorType.VARBINARY).writeVarBinary(value);
	}

	@Override
	public void writeVarBinary(ByteBuffer value, int offset, int length) {
	getWriter(MinorType.VARBINARY).writeVarBinary(value, offset, length);
	}

	@Override
	public void writeLargeVarBinary(byte[] value) {
	getWriter(MinorType.LARGEVARBINARY).writeLargeVarBinary(value);
	}

	@Override
	public void writeLargeVarBinary(byte[] value, int offset, int length) {
	getWriter(MinorType.LARGEVARBINARY).writeLargeVarBinary(value, offset, length);
	}

	@Override
	public void writeLargeVarBinary(ByteBuffer value) {
	getWriter(MinorType.LARGEVARBINARY).writeLargeVarBinary(value);
	}

	@Override
	public void writeLargeVarBinary(ByteBuffer value, int offset, int length) {
	getWriter(MinorType.LARGEVARBINARY).writeLargeVarBinary(value, offset, length);
	}

	@Override
	public void writeVarChar(Text value) {
	getWriter(MinorType.VARCHAR).writeVarChar(value);
	}

	@Override
	public void writeVarChar(String value) {
	getWriter(MinorType.VARCHAR).writeVarChar(value);
	}

	@Override
	public void writeLargeVarChar(Text value) {
	getWriter(MinorType.LARGEVARCHAR).writeLargeVarChar(value);
	}

	@Override
	public void writeLargeVarChar(String value) {
	getWriter(MinorType.LARGEVARCHAR).writeLargeVarChar(value);
	}

	@Override
	public void writeExtension(Object value) {
	getWriter(MinorType.EXTENSIONTYPE).writeExtension(value);
	}

	@Override
	public void addExtensionTypeWriterFactory(ExtensionTypeWriterFactory factory) {
	getWriter(MinorType.EXTENSIONTYPE).addExtensionTypeWriterFactory(factory);
	}

	public void addExtensionTypeWriterFactory(ExtensionTypeWriterFactory factory, ArrowType arrowType) {
	getWriter(MinorType.EXTENSIONTYPE, arrowType).addExtensionTypeWriterFactory(factory);
	}

	@Override
	public void allocate() {
	getWriter().allocate();
	}

	@Override
	public void clear() {
	getWriter().clear();
	}

	@Override
	public Field getField() {
	return getWriter().getField();
	}

	@Override
	public int getValueCapacity() {
	return getWriter().getValueCapacity();
	}

	@Override
	public void close() throws Exception {
	getWriter().close();
	}

	/**
	* Convert the writer to a PromotableViewWriter.
	*
	* @return The writer as a PromotableViewWriter.
	*/
	public PromotableViewWriter toViewWriter() {
	PromotableViewWriter promotableViewWriter = new PromotableViewWriter(unionVector, parentContainer, nullableStructWriterFactory);
	promotableViewWriter.position = position;
	promotableViewWriter.writer = writer;
	promotableViewWriter.state = state;
	promotableViewWriter.unionVector = unionVector;
	promotableViewWriter.type = MinorType.LISTVIEW;
	return promotableViewWriter;
	}
	}