jackye1995 commented on code in PR #6449: URL: https://github.com/apache/iceberg/pull/6449#discussion_r1063963570
########## delta-lake/src/main/java/org/apache/iceberg/delta/DeltaLakeTypeToType.java: ########## @@ -0,0 +1,158 @@ +/* + * 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.iceberg.delta; + +import io.delta.standalone.types.ArrayType; +import io.delta.standalone.types.BinaryType; +import io.delta.standalone.types.BooleanType; +import io.delta.standalone.types.ByteType; +import io.delta.standalone.types.DataType; +import io.delta.standalone.types.DateType; +import io.delta.standalone.types.DecimalType; +import io.delta.standalone.types.DoubleType; +import io.delta.standalone.types.FloatType; +import io.delta.standalone.types.IntegerType; +import io.delta.standalone.types.LongType; +import io.delta.standalone.types.MapType; +import io.delta.standalone.types.ShortType; +import io.delta.standalone.types.StringType; +import io.delta.standalone.types.StructField; +import io.delta.standalone.types.StructType; +import io.delta.standalone.types.TimestampType; +import java.util.List; +import org.apache.iceberg.relocated.com.google.common.collect.Lists; +import org.apache.iceberg.types.Type; +import org.apache.iceberg.types.Types; + +class DeltaLakeTypeToType extends DeltaLakeDataTypeVisitor<Type> { + private final StructType root; + private int nextId = 0; + + DeltaLakeTypeToType() { + this.root = null; + } + + DeltaLakeTypeToType(StructType root) { + this.root = root; + this.nextId = root.getFields().length; + } + + private int getNextId() { + int next = nextId; + nextId += 1; + return next; + } + + @Override + @SuppressWarnings("ReferenceEquality") + public Type struct(StructType struct, List<Type> types) { + StructField[] fields = struct.getFields(); + List<Types.NestedField> newFields = Lists.newArrayListWithExpectedSize(fields.length); + boolean isRoot = root == struct; + for (int i = 0; i < fields.length; i += 1) { + StructField field = fields[i]; + Type type = types.get(i); + + int id; + if (isRoot) { + // for new conversions, use ordinals for ids in the root struct + id = i; + } else { + id = getNextId(); + } + + // TODO: refactor const string + String doc = + field.getMetadata().contains("comment") + ? field.getMetadata().get("comment").toString() + : null; + + if (field.isNullable()) { + newFields.add(Types.NestedField.optional(id, field.getName(), type, doc)); + } else { + newFields.add(Types.NestedField.required(id, field.getName(), type, doc)); + } + } + + return Types.StructType.of(newFields); + } + + @Override + public Type field(StructField field, Type typeResult) { + return typeResult; + } + + @Override + public Type array(ArrayType array, Type elementType) { + if (array.containsNull()) { + return Types.ListType.ofOptional(getNextId(), elementType); + } else { + return Types.ListType.ofRequired(getNextId(), elementType); + } + } + + @Override + public Type map(MapType map, Type keyType, Type valueType) { + if (map.valueContainsNull()) { + return Types.MapType.ofOptional(getNextId(), getNextId(), keyType, valueType); + } else { + return Types.MapType.ofRequired(getNextId(), getNextId(), keyType, valueType); + } + } + + @SuppressWarnings("checkstyle:CyclomaticComplexity") + @Override + public Type atomic(DataType atomic) { + // TODO: pay attention to Delta's NullType, currently unhandled Review Comment: based on the impl now, we will just say unsupported, which is fine, so this TODO can be removed? -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
