Neo4j与 java项目集成 采用 JAVA Driver连接（java驱动包）实现对数据操作

嵌入式开发模式，要求必须在关闭Neo4j的情况下操作，切必须在Neo4j所在的电脑本地才能运行嵌入式开发程序。嵌入式模式下，neo4j 是不能启动的，所以不能访问neo4j的图形界面。一般应用 使用 java driver 就可以， 嵌入式开发一般是用于对图数据进行底层操作、创建自定义组件。

neo4j.properties

# 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

Neo4j是一个嵌入式，基于磁盘的，支持完整事务的Java持久化引擎，它在图像中而不是表中存储数据。Neo4j提供了大规模可扩展性，在一台机器上可以处理数十亿节点/关系/属性的图像，可以扩展到多台机器并行运行。

相对于关系数据库来说，图形数据库善于处理大量复杂、互连接、低结构化的数据，这些数据变化迅速，需要频繁的查询——在关系数据库中，这些查询会导致大量的表连接，因此会产生性能上的问题。

Neo4j重点解决了拥有大量连接的传统RDBMS在查询时出现的性能衰退问题。通过围绕图形进行数据建模，Neo4j会以相同的速度遍历节点与边，其遍历速度与构成图形的数据量没有任何关系。

此外，Neo4j还提供了非常快的图形算法、推荐系统和OLAP风格的分析，而这一切在目前的RDBMS系统中都是无法实现的。

转载，仅供参考。