原文载自：http://blog.csdn.net/yidian815/article/details/12887259
嵌入式：
引入neo4j依赖
org.neo4j neo4j 1.9.4
创建一个neo4j.properties（数据库的配置文件）
# Default values for the low-level graph engine #neostore.nodestore.db.mapped_memory=25M #neostore.relationshipstore.db.mapped_memory=50M #neostore.propertystore.db.mapped_memory=90M #neostore.propertystore.db.strings.mapped_memory=130M #neostore.propertystore.db.arrays.mapped_memory=130M # Autoindexing # Enable auto-indexing for nodes, default is false #node_auto_indexing=true # The node property keys to be auto-indexed, if enabled #node_keys_indexable=name,age # Enable auto-indexing for relationships, default is false #relationship_auto_indexing=true # The relationship property keys to be auto-indexed, if enabled #relationship_keys_indexable=name,age # Keep logical logs, needed for online backups to work keep_logical_logs=true # Enable online backups to be taken from this database. online_backup_enabled=true # Uncomment and specify these lines for running Neo4j in High Availability mode. # ha.server_id is a unique integer for each instance of the Neo4j database in the cluster. # (as opposed to the coordinator instance IDs) # example: ha.server_id=1 #ha.server_id= # ha.coordinators is a comma-separated list (without spaces) of the host:port of where to # find one or more of the Neo4j coordinator servers. # Avoid localhost due to IP resolution issues on some systems. # example: ha.coordinators=localhost:2181,1.2.3.4:4321 #ha.coordinators=localhost:2181 # You can also, optionally, configure the ha.cluster_name. This is the name of the cluster this # instance is supposed to join. Accepted characters are alphabetical, numerical, dot and dash. # This configuration is useful if you have multiple Neo4j HA clusters managed by the same # Coordinator cluster. # Example: ha.cluster_name = my.neo4j.ha.cluster #ha.cluster_name = # IP and port for this instance to bind to to communicate data with the # other neo4j instances in the cluster. This is broadcasted to the other # cluster members, so different members can have different communication ports. # Optional if the members are on different machines so the IP is different for every member. #ha.server = localhost:6001 # The interval at which slaves will pull updates from the master. Comment out # the option to disable periodic pulling of updates. Unit is seconds. ha.pull_interval = 10 # The session timeout for the zookeeper client. Lower values make new master # election happen closer to the master loosing connection but also more sensitive # to zookeeper quorum hiccups. If experiencing master switches without reason # consider increasing this value. Unit is seconds #ha.zk_session_timeout = 5 # Amount of slaves the master will try to push a transaction to upon commit (default is 1). # The master will optimistically continue and not fail the transaction even if it fails to # reach the push factor. Setting this to 0 will increase write performance when writing # through master but could potentially lead to branched data (or loss of transaction) # if the master goes down. #ha.tx_push_factor=1 # Strategy the master will use when pushing data to slaves (if the push factor is greater than 0). # There are two options available "fixed" (default) or "round_robin". Fixed will start by # pushing to slaves ordered by server id (highest first) improving performance since the # slaves only have to cache up one transaction at a time. #ha.tx_push_strategy=fixed # Enable this to be able to upgrade a store from 1.4 -> 1.5 or 1.4 -> 1.6 #allow_store_upgrade=true # Enable this to specify a parser other than the default one. 1.5, 1.6, 1.7 are available #cypher_parser_version=1.6
java文件（neo4j示例文件修改而来）
package org.easypoint; import java.io.File; import java.io.IOException; import org.neo4j.graphdb.Direction; import org.neo4j.graphdb.GraphDatabaseService; import org.neo4j.graphdb.Node; import org.neo4j.graphdb.Relationship; import org.neo4j.graphdb.RelationshipType; import org.neo4j.graphdb.Transaction; import org.neo4j.graphdb.factory.GraphDatabaseFactory; import org.neo4j.kernel.impl.util.FileUtils; public class Learn1 { private static final String DB_PATH = "target/neo4j-hello-db"; String greeting; // START SNIPPET: vars GraphDatabaseService graphDb; Node firstNode; Node secondNode; Relationship relationship; // END SNIPPET: vars // START SNIPPET: createReltype private static enum RelTypes implements RelationshipType { KNOWS } // END SNIPPET: createReltype public static void main( final String[] args ) { Learn1 hello = new Learn1(); hello.createDb(); hello.removeData(); hello.shutDown(); } void createDb() { clearDb(); // START SNIPPET: startDb graphDb = new GraphDatabaseFactory() .newEmbeddedDatabaseBuilder( "target/database/learn1" ) .loadPropertiesFromFile(Learn1.class.getResource("/").getPath()+"neo4j.properties" ) .newGraphDatabase(); registerShutdownHook( graphDb ); // END SNIPPET: startDb // START SNIPPET: transaction Transaction tx = graphDb.beginTx(); try { // Updating operations go here // END SNIPPET: transaction // START SNIPPET: addData firstNode = graphDb.createNode(); firstNode.setProperty( "message", "Hello, " ); secondNode = graphDb.createNode(); secondNode.setProperty( "message", "World!" ); relationship = firstNode.createRelationshipTo( secondNode, RelTypes.KNOWS ); relationship.setProperty( "message", "brave Neo4j " ); // END SNIPPET: addData // START SNIPPET: readData System.out.print( firstNode.getProperty( "message" ) ); System.out.print( relationship.getProperty( "message" ) ); System.out.print( secondNode.getProperty( "message" ) ); // END SNIPPET: readData greeting = ( (String) firstNode.getProperty( "message" ) ) + ( (String) relationship.getProperty( "message" ) ) + ( (String) secondNode.getProperty( "message" ) ); // START SNIPPET: transaction tx.success(); } finally { tx.finish(); } // END SNIPPET: transaction } private void clearDb() { try { FileUtils.deleteRecursively( new File( DB_PATH ) ); } catch ( IOException e ) { throw new RuntimeException( e ); } } void removeData() { Transaction tx = graphDb.beginTx(); try { // START SNIPPET: removingData // let's remove the data firstNode.getSingleRelationship( RelTypes.KNOWS, Direction.OUTGOING ).delete(); firstNode.delete(); secondNode.delete(); // END SNIPPET: removingData tx.success(); } finally { tx.finish(); } } void shutDown() { System.out.println(); System.out.println( "Shutting down database ..." ); // START SNIPPET: shutdownServer graphDb.shutdown(); // END SNIPPET: shutdownServer } // START SNIPPET: shutdownHook private static void registerShutdownHook( final GraphDatabaseService graphDb ) { // Registers a shutdown hook for the Neo4j instance so that it // shuts down nicely when the VM exits (even if you "Ctrl-C" the // running application). Runtime.getRuntime().addShutdownHook( new Thread() { @Override public void run() { graphDb.shutdown(); } } ); } // END SNIPPET: shutdownHook } 运行java文件，可以看到在target/database/下创建了一个learn1的数据库。
从java代码我们也可以看出，neo4j数据库主要依靠node,relationship和property来存储数据，利用relationship将各个node链接起来。
服务式：
1.简单暴力连接（使用jdbc）：
2.使用JERSEY
添加依赖jar
com.sun.jersey jersey-project 1.17 com.sun.jersey jersey-server 1.17 com.sun.jersey jersey-client 1.17 com.sun.jersey jersey-core 1.17 com.sun.jersey jersey-json 1.17
新建java类Learn1Rest
package org.easypoint; import com.sun.jersey.api.client.ClientResponse; import com.sun.jersey.api.client.WebResource; import com.sun.jersey.api.client.Client; import java.net.URI; import javax.ws.rs.core.MediaType; /** * 服务式neo4j连接 */ public class Learn1Rest { public static void main(String args[]){ Learn1Rest lr = new Learn1Rest(); URI firstNode = lr.createNode(); lr.addProperty( firstNode, "name", "Joe Strummer" ); URI secondNode = lr.createNode(); lr.addProperty( secondNode, "band", "The Clash" ); } public URI createNode(){ String SERVER_ROOT_URI = "http://61.xxx.xxx.xx:7474/db/data/"; final String nodeEntryPointUri = SERVER_ROOT_URI + "node"; WebResource resource = Client.create().resource(nodeEntryPointUri); ClientResponse response = resource.accept( MediaType.APPLICATION_JSON ) .type(MediaType.APPLICATION_JSON) .entity("{}") .post(ClientResponse.class); final URI location = response.getLocation(); System.out.println( String.format("POST to [%s], status code [%d], location header [%s]", nodeEntryPointUri, response.getStatus(), location.toString() ) ); response.close(); return location; } public void addProperty(URI nodeUri,String propertyName, String propertyValue){ String propertyUri = nodeUri.toString() + "/properties/" + propertyName; WebResource resource = Client.create() .resource( propertyUri ); ClientResponse response = resource.accept( MediaType.APPLICATION_JSON ) .type( MediaType.APPLICATION_JSON ) .entity( "\"" + propertyValue + "\"" ) .put( ClientResponse.class ); System.out.println( String.format( "PUT to [%s], status code [%d]", propertyUri, response.getStatus() ) ); response.close(); } }
执行成功
数据库查询：
