/*
* Copyright (c) 2002-2009 "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.shell.kernel.apps;
import java.rmi.RemoteException;
import org.neo4j.graphdb.Direction;
import org.neo4j.graphdb.Node;
import org.neo4j.graphdb.Relationship;
import org.neo4j.graphdb.RelationshipType;
import org.neo4j.shell.AppCommandParser;
import org.neo4j.shell.OptionDefinition;
import org.neo4j.shell.OptionValueType;
import org.neo4j.shell.Output;
import org.neo4j.shell.Session;
import org.neo4j.shell.ShellException;
/**
* Mimics the POSIX application "mkdir", but neo4j has relationships instead of
* directories (if you look at Neo4j in a certain perspective).
*/
public class Mkrel extends GraphDatabaseApp
{
public static final String KEY_LAST_CREATED_NODE = "LAST_CREATED_NODE";
public static final String KEY_LAST_CREATED_RELATIONSHIP = "LAST_CREATED_RELATIONSHIP";
/**
* Constructs a new application which can create relationships and nodes
* in Neo4j.
*/
public Mkrel()
{
this.addOptionDefinition( "t", new OptionDefinition( OptionValueType.MUST,
"The relationship type" ) );
this.addOptionDefinition( "d", new OptionDefinition( OptionValueType.MUST,
"The direction: " + this.directionAlternatives() + "." ) );
this.addOptionDefinition( "c", new OptionDefinition( OptionValueType.NONE,
"Supplied if there should be created a new node" ) );
this.addOptionDefinition( "v", new OptionDefinition( OptionValueType.NONE,
"Verbose mode: display created nodes/relationships" ) );
}
@Override
public String getDescription()
{
return "Creates a relationship to a new or existing node, f.ex:\n" +
"mkrel -ct KNOWS (will create a relationship to a new node)\n" +
"mkrel -t KNOWS 123 (will create a relationship to node with id 123)";
}
@Override
protected String exec( AppCommandParser parser, Session session, Output out )
throws ShellException, RemoteException
{
assertCurrentIsNode( session );
boolean createNode = parser.options().containsKey( "c" );
boolean suppliedNode = !parser.arguments().isEmpty();
Node node = null;
if ( createNode )
{
node = getServer().getDb().createNode();
session.set( KEY_LAST_CREATED_NODE, "" + node.getId() );
}
else if ( suppliedNode )
{
node = getNodeById( Long.parseLong( parser.arguments().get( 0 ) ) );
}
else
{
throw new ShellException( "Must either create node (-c)"
+ " or supply node id as the first argument" );
}
if ( parser.options().get( "t" ) == null )
{
throw new ShellException( "Must supply relationship type "
+ "(-t <relationship-type-name>)" );
}
RelationshipType type = this.getRelationshipType( parser.options().get(
"t" ) );
Direction direction = this.getDirection( parser.options().get( "d" ) );
Node currentNode = getCurrent( session ).asNode();
Node startNode = direction == Direction.OUTGOING ? currentNode : node;
Node endNode = direction == Direction.OUTGOING ? node : currentNode;
Relationship relationship =
startNode.createRelationshipTo( endNode, type );
session.set( KEY_LAST_CREATED_RELATIONSHIP, relationship.getId() );
boolean verbose = parser.options().containsKey( "v" );
if ( createNode && verbose )
{
out.println( "Node " + getDisplayName(
getServer(), session, node, false ) + " created" );
}
if ( verbose )
{
out.println( "Relationship " + getDisplayName(
getServer(), session, relationship, true, false ) +
" created" );
}
return null;
}
}