/*
* Copyright (c) 2002-2010 "Neo Technology,"
* Network Engine for Objects in Lund AB [http://neotechnology.com]
*
* This file is part of Neo4j.
*
* Neo4j is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package org.neo4j.kernel;
import java.io.Serializable;
import java.rmi.RemoteException;
import java.util.Map;
import org.neo4j.graphdb.GraphDatabaseService;
/**
* Can start and stop a shell server via reflection if the shell should happen
* to be on the classpath, else it will gracefully say that it isn't there.
*/
class ShellService
{
private final GraphDatabaseService graphDb;
private final Object shellServer;
ShellService( GraphDatabaseService graphDb, Map<String,Serializable> config )
throws ShellNotAvailableException, RemoteException
{
this.graphDb = graphDb;
if ( !shellDependencyAvailable() )
{
throw new ShellNotAvailableException();
}
this.shellServer = startShellServer( config );
}
private boolean shellDependencyAvailable()
{
try
{
Class.forName( "org.neo4j.shell.ShellServer" );
return true;
}
catch ( Throwable t )
{
return false;
}
}
private Object startShellServer( Map<String,Serializable> config )
throws RemoteException
{
Integer port = (Integer) getConfig( config, "port", "DEFAULT_PORT" );
String name = (String) getConfig( config, "name", "DEFAULT_NAME" );
try
{
Class<?> shellServerClass =
Class
.forName( "org.neo4j.shell.kernel.GraphDatabaseShellServer" );
Object shellServer =
shellServerClass.getConstructor( GraphDatabaseService.class )
.newInstance( graphDb );
shellServer.getClass().getMethod( "makeRemotelyAvailable",
Integer.TYPE, String.class ).invoke( shellServer, port, name );
return shellServer;
}
catch ( Exception e )
{
throw new RemoteException( "Couldn't start shell '" + name
+ "' at port " + port, e );
}
}
private Serializable getConfig( Map<String,Serializable> config,
String key, String defaultVariableName ) throws RemoteException
{
Serializable result = config.get( key );
if ( result == null )
{
try
{
result =
(Serializable) Class.forName(
"org.neo4j.shell.impl.AbstractServer" )
.getDeclaredField( defaultVariableName ).get( null );
}
catch ( Exception e )
{
throw new RemoteException( "Default variable not found", e );
}
}
return result;
}
public boolean shutdown() throws ShellNotAvailableException
{
try
{
shellServer.getClass().getMethod( "shutdown" ).invoke( shellServer );
return true;
}
catch ( Exception e )
{
// TODO Really swallow this? Why not, who cares?
return false;
}
}
static class ShellNotAvailableException extends Exception
{
public ShellNotAvailableException()
{
super();
}
}
}