org.eobjects.analyzer.beans.api.Initialize Maven / Gradle / Ivy
/**
* eobjects.org AnalyzerBeans
* Copyright (C) 2010 eobjects.org
*
* This copyrighted material is made available to anyone wishing to use, modify,
* copy, or redistribute it subject to the terms and conditions of the GNU
* Lesser General Public License, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
* for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this distribution; if not, write to:
* Free Software Foundation, Inc.
* 51 Franklin Street, Fifth Floor
* Boston, MA 02110-1301 USA
*/
package org.eobjects.analyzer.beans.api;
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* Annotation that marks method as an initializing method. Use this annotation
* if you need to initialize the state of a bean before it starts executing a
* job.
*
* The @Initialize annotation can be used on methods in the following component
* types:
*
*
* - AnalyzerBeans
* - TransformerBeans
* - FilterBeans
* - Dictionary
* - SynonymCatalog
* - StringPattern
* - ... and custom configuration elements, such as custom datastores and
* custom task runners (in which case the semantics are a bit different - they
* will only be initialized once, just after loading the configuration).
*
*
* The method is invoked after any @Configured and @Provided methods/fields are
* invoked/assigned but before any business methods (such as run(...) on an
* analyzer) are invoked.
*
* For distributed execution, the {@link #distributed()} property will be
* consulted to determine if the initialization methods should be executed on
* all nodes or just on a single (typically master) node, before distribution.
*
* @Initialize is often used in conjunction with the @Close annotation.
*
* @see Close
*/
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
@Documented
@Inherited
public @interface Initialize {
/**
* Determines if the initialize method is to be executed in a distributed
* fashion, potentially on multiple nodes in a cluster.
*
* By default initialization methods will only initialize internal state of
* the component, and is thus fully distributable. But if the initialization
* touches outside resources, such as datastores, files or other, then the
* initialization is typically NOT distributable, since timing of the
* initializations accross the cluster isn't predictable.
*
* @return true if this initialization method is distributable. In that case
* it will be invoked on all nodes of a cluster. If the value is
* false, the initialization method will ONLY be invoked on a single
* (master) node and all other nodes will not have this particular
* initialization method invoked.
*/
public boolean distributed() default true;
}