教你怎样在java程序中引入neo4j数据库

教你怎样在java程序中引入neo4j数据库2014-08-17随着关系型数据库在某些方面的力不从心，了解当下流行的各种数据库模式的特点和性能，无疑会给我们提供更多的选择和方向。 neo4j是一种图形数据库，在遍历和关联查询方面具有突出的优势。废话少说，深入了解neo4j之前，先让我们尝试一下怎样在程序中使用neo4j。

neo4j采用java语言开发，如果我们要在java程序中以内嵌方式使用neo4j，只需导入neo4j的对应包即可。

首先，我们来创建一个maven项目并修改pom.xml添加对neo4j的依赖。

<？xml version="1.0" encoding="UTF-8"？><project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"><modelVersion>4.0.0</modelVersion><groupId>neo4j-learn</groupId><artifactId>neo4j-learn</artifactId><version>1.0-SNAPSHOT</version><dependencies><dependency><groupId>org.neo4j</groupId><artifactId>neo4j</artifactId><version>1.9.4</version></dependency></dependencies></project>

然后，我们在项目中创建一个neo4j.properties（数据库的配置文件）文件和一个java类（调用数据库）。

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 workkeep_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