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API for the JNI components of the QuasarDB API for Java. Should not be included directly.

There is a newer version: 3.14.1

package net.quasardb.qdb.ts;

import java.util.Optional;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import net.quasardb.qdb.Session;
import net.quasardb.qdb.jni.qdb;
import net.quasardb.qdb.jni.Reference;
import net.quasardb.qdb.exception.InputException;


/**
 * Represents a timeseries query.
 *
 * Use this class directly if you're planning on writing complex, custom
 * queries. If your queries are relatively simple, consider using the
 * {@link QueryBuilder} instead.
 *
 * @see QueryBuilder
 */
public final class Query {
    private static final Logger logger = LoggerFactory.getLogger(Writer.class);

    private String query;

    protected Query() {
    }

    protected Query(String query) {
        this.query = query;
    }

    /**
     * Creates a new, empty query instance.
     */
    public static Query create() {
        return new Query();
    }

    /**
     * Returns new Query instance based on a string.
     *
     * @param query The query string to execute. Refer to the QuasarDB documentation
     *              for the full query syntax.
     */
    public static Query of(String query) {
        logger.debug("Executing query: {}", query);
        return new Query(query);
    }

    public Result execute(Session session) {
        if (this.query == null) {
            throw new InputException("Cannot execute an empty query");
        }

        Reference result = new Reference();

        qdb.query_execute(session.handle(), this.query, result);

        return result.value;
    }
}