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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.impl;

import java.io.File;

import org.neo4j.shell.Console;
import org.neo4j.shell.ShellClient;

/**
 * Implements the {@link Console} interface with jLine using reflections only,
 * since we don't wan't a runtime dependency on jLine.
 */
public class JLineConsole implements Console
{
    private final Object consoleReader;

    static JLineConsole newConsoleOrNullIfNotFound( ShellClient client )
    {
        try
        {
            Object consoleReader =
                Class.forName( "jline.console.ConsoleReader" ).newInstance();
            consoleReader.getClass().getMethod( "setBellEnabled",
                Boolean.TYPE ).invoke( consoleReader, false );
            consoleReader.getClass().getMethod( "setExpandEvents", Boolean.TYPE ).invoke(
                    consoleReader, false );
            consoleReader.getClass().getMethod( "setHistoryEnabled", Boolean.TYPE ).invoke(
                    consoleReader, true );

            Object completer = Class.forName( JLineConsole.class.getPackage().getName() + "." +
                    "ShellTabCompleter" ).getConstructor( ShellClient.class ).newInstance( client );
            Class completerClass = Class.forName( "jline.console.completer.Completer" );
            consoleReader.getClass().getMethod( "addCompleter",
                completerClass ).invoke( consoleReader, completer );

            Class historyClass = Class.forName( "jline.console.history.History" );
            Object history = Class.forName( "jline.console.history.FileHistory" ).getConstructor(
                    File.class ).newInstance( new File( System.getProperty(
                            "user.home" ), ".neo4j_shell_history" ) );
            consoleReader.getClass().getMethod( "setHistory", historyClass ).invoke( consoleReader, history );

            return new JLineConsole( consoleReader, client );
        }
        catch ( RuntimeException e )
        {
            // Only checked exceptions should cause us to return null,
            // a runtime exception is not expected - it could be an OOM
            // for instance, throw instead.
            throw e;
        }
        catch ( Exception e )
        {
            return null;
        }
    }

    private JLineConsole( Object consoleReader, ShellClient client )
    {
        this.consoleReader = consoleReader;
    }

    @Override
    public void format( String format, Object... args )
    {
        System.out.print( format );
    }

    @Override
    public String readLine( String prompt )
    {
        try
        {
            consoleReader.getClass().getMethod( "setPrompt", String.class ).invoke(
                    consoleReader, prompt );
            Class fileHistoryClass = Class.forName( "jline.console.history.FileHistory" );
            Object history = consoleReader.getClass().getMethod( "getHistory" ).invoke(
                    consoleReader );
            Class.forName( "jline.console.history.FileHistory" ).getMethod( "flush" ).invoke(
                    history );
            return ( String ) consoleReader.getClass().getMethod( "readLine" ).
                invoke( consoleReader );
        }
        catch ( RuntimeException e )
        {
            throw e;
        }
        catch ( Exception e )
        {
            throw new RuntimeException( e );
        }
    }
}