org.neo4j.driver.internal.InternalBookmark Maven / Gradle / Ivy

/*
 * Copyright (c) "Neo4j"
 * Neo4j Sweden AB [http://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
 *
 *     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.neo4j.driver.internal;

import static java.util.Objects.requireNonNull;

import java.io.Serial;
import java.io.Serializable;
import java.util.Collections;
import java.util.HashSet;
import java.util.Objects;
import java.util.Set;
import org.neo4j.driver.Bookmark;
import org.neo4j.driver.internal.util.Iterables;

public final class InternalBookmark implements Bookmark, Serializable {
    @Serial
    private static final long serialVersionUID = 8196096018245038950L;

    private static final InternalBookmark EMPTY = new InternalBookmark(Collections.emptySet());

    private final Set values;

    private InternalBookmark(Set values) {
        requireNonNull(values);
        this.values = values;
    }

    public static Bookmark empty() {
        return EMPTY;
    }

    @SuppressWarnings("deprecation")
    public static Bookmark from(Iterable bookmarks) {
        if (bookmarks == null) {
            return empty();
        }

        int size = Iterables.count(bookmarks);
        if (size == 0) {
            return empty();
        } else if (size == 1) {
            return from(bookmarks.iterator().next());
        }

        Set newValues = new HashSet<>();
        for (Bookmark value : bookmarks) {
            if (value == null) {
                continue; // skip any null bookmark value
            }
            newValues.addAll(value.values());
        }
        return new InternalBookmark(newValues);
    }

    private static Bookmark from(Bookmark bookmark) {
        if (bookmark == null) {
            return empty();
        }
        // it is safe to return the given bookmark as bookmarks values can not be modified once it is created.
        return bookmark;
    }

    /**
     * Used to extract bookmark from metadata from server.
     */
    public static Bookmark parse(String value) {
        if (value == null) {
            return empty();
        }
        return new InternalBookmark(Collections.singleton(value));
    }

    /**
     * Used to reconstruct bookmark from values.
     */
    public static Bookmark parse(Set values) {
        if (values == null) {
            return empty();
        }
        return new InternalBookmark(values);
    }

    @Override
    @Deprecated
    public boolean isEmpty() {
        return values.isEmpty();
    }

    @Override
    public String value() {
        return values.isEmpty() ? null : values.iterator().next();
    }

    @Override
    @Deprecated
    public Set values() {
        return Collections.unmodifiableSet(values);
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) {
            return true;
        }
        if (o == null || getClass() != o.getClass()) {
            return false;
        }
        InternalBookmark bookmark = (InternalBookmark) o;
        return Objects.equals(values, bookmark.values);
    }

    @Override
    public int hashCode() {
        return Objects.hash(values);
    }

    @Override
    public String toString() {
        return "Bookmark{values=" + values + "}";
    }
}