/*
* 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.graphdb;
import java.io.Serializable;
import java.util.Map;
import org.neo4j.kernel.EmbeddedGraphDatabase;
/**
* The main access point to a running Neo4j instance. The most common
* implementation is the {@link EmbeddedGraphDatabase EmbeddedGraphDatabase} class, which is used to
* embed Neo4j in an application. Typically, you would create an
* <code>EmbeddedGraphDatabase</code> instance as follows:
* <code>
* <pre>GraphDatabaseService graphDb = new EmbeddedGraphDatabase( "var/graphDb" );
* // ... use Neo4j
* graphDb.shutdown();</pre>
* </code>
* GraphDatabaseService provides operations to {@link #enableRemoteShell enable the shell},
* {@link #createNode() create nodes}, {@link #getNodeById(long) get nodes
* given an id}, get the {@link #getReferenceNode() reference node} and
* ultimately {@link #shutdown() shutdown Neo4j}.
* <p>
* Please note that all operations that read or write to the node space must be
* invoked in a {@link Transaction transactional context}. Failure to do so
* will result in a {@link NotInTransactionException} being thrown.
*/
public interface GraphDatabaseService
{
/**
* Creates a new node.
* @return the created node.
*/
public Node createNode();
/**
* Looks up a node by id.
* @param id the id of the node
* @return the node with id <code>id</code> if found
* @throws NotFoundException if not found
*/
public Node getNodeById( long id );
/**
* Looks up a relationship by id.
* @param id the id of the relationship
* @return the relationship with id <code>id</code> if found
* @throws NotFoundException if not found
*/
public Relationship getRelationshipById(long id);
/**
* Returns the reference node, which is a "starting point" in the node
* space. Usually, a client attaches relationships to this node that leads
* into various parts of the node space. For more information about common
* node space organizational patterns, see the design guide at
* <a href="http://neo4j.org/doc">http://neo4j.org/doc</a>.
* @return the reference node
* @throws NotFoundException if unable to get the reference node
*/
public Node getReferenceNode();
/**
* Returns all nodes in the node space.
* @return all nodes in the node space
*/
public Iterable<Node> getAllNodes();
/**
* Returns all relationship types currently in the underlying store. Relationship
* types are added to the underlying store the first time they are used in
* a successfully commited {@link Node#createRelationshipTo node.createRelationshipTo(...)}. Note that
* this method is guaranteed to return all known relationship types, but
* it does not guarantee that it won't return <i>more</i> than that (e.g.
* it can return "historic" relationship types that no longer have any
* relationships in the node space).
* @return all relationship types in the underlying store
*/
public Iterable<RelationshipType> getRelationshipTypes();
/**
* Shuts down Neo4j. After this method has been invoked, it's invalid to
* invoke any methods in the Neo4j API and all references to this instance
* of GraphDatabaseService should be discarded.
*/
public void shutdown();
/**
* Enables remote shell access (with default configuration) to this Neo4j
* instance, if the Neo4j <code>shell</code> component is available on the
* classpath. This method is identical to invoking
* {@link #enableRemoteShell(Map) enableRemoteShell( null )}.
* @return <code>true</code> if the shell has been enabled,
* <code>false</code> otherwise (<code>false</code> usually indicates that
* the <code>shell</code> jar dependency is not on the classpath)
*/
public boolean enableRemoteShell();
/**
* Enables remote shell access to this Neo4j instance, if the Neo4j
* <code>shell</code> component is available on the classpath. This will
* publish a shell access interface on an RMI registry on localhost (with
* configurable port and RMI binding name). It can be accessed by a
* client that implements <code>org.neo4j.util.shell.ShellClient</code>
* from the Neo4j <code>shell</code> project. Typically, the
* <code>shell</code> binary package is used (see
* <a href="http://neo4j.org/download">neo4j.org/download</a>).
* <p>
* The shell is parameterized by a map of properties passed in to this
* method. Currently, two properties are used:
* <ul>
* <li><code>port</code>, an {@link Integer} describing the port of the RMI
* registry where the Neo4j shell will be bound, defaults to
* <code>1337</code> <li><code>name</code>, the {@link String} under which
* the Neo4j shell will be bound in the RMI registry, defaults to
* <code>shell</code> </ul>
* @param initialProperties a set of properties that will be used to
* configure the remote shell, or <code>null</code> if the default
* properties should be used
* @return <code>true</code> if the shell has been enabled,
* <code>false</code> otherwise (<code>false</code> usually indicates that
* the <code>shell</code> jar dependency is not on the classpath)
* @throws ClassCastException if the shell library is available, but one
* (or more) of the configuration properties have an unexpected type
* @throws IllegalStateException if the shell library is available, but
* the remote shell can't be enabled anyway
*/
public boolean enableRemoteShell(
Map<String, Serializable> initialProperties );
/**
* Starts a new transaction and associates it with the current thread.
* @return a new transaction instance
*/
public Transaction beginTx();
}