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Implementation of the Neo4j JDBC driver.
There is a newer version: 6.0.1
/*
 * Copyright (c) 2023-2024 "Neo4j,"
 * Neo4j Sweden AB [https://neo4j.com]
 *
 * This file is part of Neo4j.
 *
 * Licensed 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
 *
 *     https://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.neo4j.jdbc.values;

import java.util.Map;
import java.util.function.Function;

/**
 * Access the keys, properties and values of an underlying unordered map by key
 * 
 * This provides only read methods. Subclasses may choose to provide additional methods
 * for changing the underlying map.
 *
 * @author Neo4j Drivers Team
 * @since 6.0.0
 */
public interface MapAccessor {

	/**
	 * Retrieve the keys of the underlying map.
	 * @return all map keys in unspecified order
	 */
	Iterable keys();

	/**
	 * Check if the list of keys contains the given key.
	 * @param key the key
	 * @return {@code true} if this map keys contains the given key otherwise
	 * {@code false}
	 */
	boolean containsKey(String key);

	/**
	 * Retrieve the value of the property with the given key.
	 * @param key the key of the property
	 * @return the property's value or a {@link NullValue} if no such key exists
	 * @throws ValueException if record has not been initialized
	 */
	Value get(String key);

	/**
	 * Retrieve the number of entries in this map.
	 * @return the number of entries in this map
	 */
	int size();

	/**
	 * Retrieve all values of the underlying collection.
	 * @return all values in unspecified order
	 */
	Iterable values();

	/**
	 * Map and retrieve all values of the underlying collection.
	 * @param mapFunction a function to map from Value to T. See {@link Values} for some
	 * predefined functions, such as {@link Values#ofBoolean()},
	 * {@link Values#ofList(Function)}.
	 * @param  the target type of mapping
	 * @return the result of mapping all values in unspecified order
	 */
	 Iterable values(Function mapFunction);

	/**
	 * Return the underlying map as a map of string keys and values converted using
	 * {@link Value#asObject()}.
	 * 
	 * This is equivalent to calling {@link #asMap(Function)} with
	 * {@link Values#ofObject()}.
	 * @return the value as a Java map
	 */
	Map asMap();

	/**
	 * Return the underlying map as a map of string keys and values converted using the
	 * supplied map function.
	 * @param mapFunction a function to map from Value to T. See {@link Values} for some
	 * predefined functions, such as {@link Values#ofBoolean()},
	 * {@link Values#ofList(Function)}.
	 * @param  the type of map values
	 * @return the value as a map from string keys to values of type T obtained from
	 * mapping the original map values, if possible
	 * @see Values for a long list of built-in conversion functions
	 */
	 Map asMap(Function mapFunction);

}