jackye1995 commented on a change in pull request #2354: URL: https://github.com/apache/iceberg/pull/2354#discussion_r605806275
########## File path: api/src/main/java/org/apache/iceberg/RowKey.java ########## @@ -0,0 +1,178 @@ +/* + * 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; + +import java.io.Serializable; +import java.util.Arrays; +import java.util.Set; +import org.apache.iceberg.exceptions.ValidationException; +import org.apache.iceberg.relocated.com.google.common.collect.Sets; +import org.apache.iceberg.types.Types; + +/** + * Row key of a table. + * <p> + * Row key is a definition of table row uniqueness, + * similar to the concept of primary key in a relational database system. + * A row should be unique in a table based on the values of each {@link RowKeyField}. + * Iceberg itself does not enforce row uniqueness based on this key. + * It is leveraged by operations such as streaming upsert. + */ +public class RowKey implements Serializable { + + private static final RowKey NOT_IDENTIFIED = new RowKey(null, Sets.newHashSet()); + + private final Schema schema; + private final RowKeyField[] fields; + + private transient volatile Set<RowKeyField> fieldSet; + + private RowKey(Schema schema, Set<RowKeyField> fields) { + this.schema = schema; + this.fields = fields.toArray(new RowKeyField[0]); + } + + /** + * Returns the {@link Schema} referenced by the row key + */ + public Schema schema() { + return schema; + } + + /** + * Return the set of {@link RowKeyField} in the row key + * <p> + * @return the set of fields in the row key + */ + public Set<RowKeyField> fields() { + return lazyFieldSet(); + } + + private Set<RowKeyField> lazyFieldSet() { + if (fieldSet == null) { + synchronized (this) { + if (fieldSet == null) { + fieldSet = Sets.newHashSet(Arrays.asList(fields)); Review comment: Yeah good point -- 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. For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
