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A library containing the JQM engine. Cannot be used alone.

There is a newer version: 2.2.9

package com.enioka.jqm.tools;

import com.enioka.jqm.jdbc.Db;
import com.enioka.jqm.jdbc.DbConn;

/**
 * Not part of any API - this an internal JQM class and may change without notice. 

 * The only public way to create an engine. It is exposed to allow different engine packagings in other JQM artifacts (and one day may
 * become the entry point of an "embedded JQM library").
 *
 */
public class JqmEngineFactory
{
    /**
     * Creates and start an engine representing the node named as the given parameter.
     * 
     * @param name
     *            name of the node, as present in the configuration (case sensitive)
     * @param handler
     *            can be null. A set of callbacks hooked on different engine life cycle events.
     * @return an object allowing to stop the engine.
     */
    public static JqmEngineOperations startEngine(String name, JqmEngineHandler handler)
    {
        JqmEngine e = new JqmEngine();
        e.start(name, handler);
        return e;
    }

    /**
     * If you already have a Db object pointing to the JQM database to use (an existing datasource) you can give it here and all the engines
     * will use it.
     * 
     * @param db
     *            the encapsulated datasource.
     */
    public static void setDatasource(Db db)
    {
        Helpers.setDb(db);
    }

    /**
     * If the database you use is brand new (empty tables) you may want to use this to initialize the metadata instead of using the meta
     * API.
     */
    public static void initializeMetadata()
    {
        // TODO: merge inside meta API.
        DbConn cnx = null;
        try
        {
            cnx = Helpers.getNewDbSession();
            Helpers.updateConfiguration(cnx);
            cnx.commit();
        }
        catch (Exception e)
        {
            throw new JqmRuntimeException("Could not set metadata", e);
        }
        finally
        {
            Helpers.closeQuietly(cnx);
        }
    }
}