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A generic command shell with a client and server part.
There is a newer version: 3.3.2
/*
 * Copyright (c) 2002-2016 "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 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see .
 */
package org.neo4j.shell.kernel.apps;

import java.rmi.RemoteException;

import org.neo4j.graphdb.Node;
import org.neo4j.graphdb.Relationship;
import org.neo4j.helpers.Service;
import org.neo4j.shell.App;
import org.neo4j.shell.AppCommandParser;
import org.neo4j.shell.Continuation;
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 "rmdir", but neo4j has relationships instead of
 * directories (if you look at Neo4j in a certain perspective).
 */
@Service.Implementation( App.class )
public class Rmrel extends TransactionProvidingApp
{
    /**
     * Constructs a new application which can delete relationships in Neo4j.
     */
    public Rmrel()
    {
        this.addOptionDefinition( "f", new OptionDefinition( OptionValueType.NONE,
            "Force deletion, i.e. disables the connectedness check" ) );
        this.addOptionDefinition( "d", new OptionDefinition( OptionValueType.NONE,
            "Also delete the node on the other side of the relationship if removing" +
            " this relationship results in it not having any relationships left" ) );
    }

    @Override
    public String getDescription()
    {
        return "Deletes a relationship, also ensuring the connectedness of the graph. That check can be ignored with -f\n" +
                "Usage: rmrel \n" +
                "   or  rmrel -f ";
    }

    @Override
    protected Continuation exec( AppCommandParser parser, Session session,
        Output out ) throws ShellException, RemoteException
    {
        assertCurrentIsNode( session );

        if ( parser.arguments().isEmpty() )
        {
            throw new ShellException(
                "Must supply relationship id to delete as the first argument" );
        }

        Node currentNode = this.getCurrent( session ).asNode();
        Relationship rel = findRel( currentNode, Long.parseLong(
            parser.arguments().get( 0 ) ) );
        rel.delete();

        Node otherNode = rel.getOtherNode( currentNode );

        boolean deleteOtherNodeIfEmpty = parser.options().containsKey( "d" );
        if ( deleteOtherNodeIfEmpty && !otherNode.hasRelationship() )
        {
            out.println( "Also deleted " + getDisplayName( getServer(), session, otherNode, false ) +
                    " due to it not having any relationships left" );
            otherNode.delete();
        }
        return Continuation.INPUT_COMPLETE;
    }

    private Relationship findRel( Node currentNode, long relId )
        throws ShellException
    {
        Relationship rel = getServer().getDb().getRelationshipById( relId );
        if ( rel.getStartNode().equals( currentNode ) || rel.getEndNode().equals( currentNode ) )
        {
            return rel;
        }
        throw new ShellException( "No relationship " + relId +
            " connected to " + currentNode );
    }
}