/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 2002-2008, Open Source Geospatial Foundation (OSGeo)
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation;
* version 2.1 of the License.
*
* This library 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.
*
*/
package org.geotools.arcsde.session;
import java.io.IOException;
import com.esri.sde.sdk.client.SeConnection;
import com.esri.sde.sdk.client.SeException;
/**
* Runnable used to interact with an ArcSDEConnection.
* <p>
* Instances of this class can be sent to {@link Session#issue(Command)} in order to be executed. A
* {@code Command} has exclusive access to the {@link SeConnection connection} for the duration of
* its {@code execute} method. This facility is used to prevent a series of complicated locks and
* try/catch/finally code.
* </p>
*
* @author Jody Garnett
*
*
*
* @source $URL$
* http://svn.osgeo.org/geotools/trunk/modules/plugin/arcsde/common/src/main/java/org/geotools
* /arcsde/session/Command.java $
*/
public abstract class Command<R> {
/**
* Executed to operate on an SeConnection, a Command is scheduled for execution on a Session.
* <p>
* Please keep in mind that a Command should be short in duration; you are sharing this
* SeConnection with other threads.
*
* @param session
* the Session the command is being executed inside
* @param connection
* the session's connection, used to interact with ArcSDE
* @return the result of the command execution, or null if the command is not meant to return
* anything (a command meant to return something should fail if not able to)
*/
public abstract R execute(ISession session, SeConnection connection) throws SeException,
IOException;
}