/*
* Copyright 2009 DuraSpace.
*
* 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.mulgara.query.operation;
import java.net.URI;
/**
* An AST element for non-server commands.
*
* @created 2007-08-09
* @author Paula Gearon
* @copyright © 2007 <a href="mailto:pgearon@users.sourceforge.net">Paula Gearon</a>
* @licence <a href="{@docRoot}/../../LICENCE.txt">Open Software License v3.0</a>
*/
public abstract class LocalCommand extends AbstractCommand {
/**
* Indicates that this operation is local.
* @return Always <code>true</code> to indicate this command is local.
*/
public final boolean isLocalOperation() {
return true;
}
/**
* Queries if this command is a request to quit.
* @return <code>false</code> for most operations, but <code>true</code> if quitting.
*/
public boolean isQuitCommand() {
return false;
}
/**
* Gets the associated server for a non-local operation.
* @return <code>null</code>
*/
public URI getServerURI() {
return null;
}
/**
* Executes the operation. This is highly specific to each operation.
* @return Data specific to the operation.
* @throws Exception specific to the operation.
*/
public Object execute() throws Exception {
return execute(null);
}
}