Neo4j简单的例子

灰太狼 2022-08-02 07:18 194阅读 0赞

系统环境：

Ubuntu 04.10 x64

一：安装

下载最新版：neo4j-community-2.2.3-unix.tar.gz  解压

cd neo4j-community-2.2.3/bin

./neo4j start

启动之后，默认的web端口是：7474

三：JAVA操作neo4j

下面例子演示了一个银行层级关系的例子

央行下面有四大行，四大行下面有各自的分行，各自的分行又有各自的支行

package com.lala.neo4j;
    
    import org.neo4j.graphdb.Label;
    
    public class BankLabel implements Label
    {
    	private String name;
    	
    	public BankLabel(String name)
    	{
    		this.name = name;
    	}
    	public String name() 
    	{
    		return name;
    	}
    }

package com.lala.neo4j;
    
    import org.neo4j.graphdb.RelationshipType;
    
    public class BankRelationshipType implements RelationshipType
    {
    	private String ship;
    	
    	public BankRelationshipType(String ship)
    	{
    		this.ship = ship;
    	}
    	public String name() 
    	{
    		return ship;
    	}
    }

package com.lala.neo4j;
    
    import org.neo4j.graphdb.GraphDatabaseService;
    import org.neo4j.graphdb.Node;
    import org.neo4j.graphdb.Transaction;
    import org.neo4j.graphdb.factory.GraphDatabaseFactory;
    
    public class Neo4j 
    {
    	/**
    	 * 标签
    	 */
    	static BankLabel top = new BankLabel("总行");
    	static BankLabel sdh = new BankLabel("四大银行");
    	static BankLabel fh = new BankLabel("分行");
    	static BankLabel zh = new BankLabel("支行");
    	
    	/**
    	 * 关系
    	 */
    	static BankRelationshipType xj = new BankRelationshipType("XJ");
    	static BankRelationshipType sj = new BankRelationshipType("SJ");
    	
    	/**
    	 * 初始化总行和分行的关系数据
    	 */
    	static void init1(GraphDatabaseService db)throws Exception
    	{
    		Node n1 = db.createNode(top);
    		n1.setProperty("name", "央行");
    		
    		Node n2 = db.createNode(sdh);
    		n2.setProperty("name", "农业银行");
    		
    		Node n3 = db.createNode(sdh);
    		n3.setProperty("name", "工商银行");
    		
    		n1.createRelationshipTo(n2, sj);
    		n2.createRelationshipTo(n1, xj);
    		
    		n1.createRelationshipTo(n3, sj);
    		n3.createRelationshipTo(n1, xj);
    	}
    	
    	/**
    	 * 初始化农业银行分行数据
    	 */
    	static void init2(GraphDatabaseService db)throws Exception
    	{
    		Node n1 = db.getNodeById(1);
    		
    		Node gd = db.createNode(fh);
    		gd.setProperty("name", "农业银行广东分行");
    		n1.createRelationshipTo(gd, sj);
    		gd.createRelationshipTo(n1, xj);
    		
    		Node hn = db.createNode(fh);
    		hn.setProperty("name", "农业银行湖南分行");
    		n1.createRelationshipTo(hn, sj);
    		hn.createRelationshipTo(n1, xj);
    		
    		Node hb = db.createNode(fh);
    		hb.setProperty("name", "农业银行湖北分行");
    		n1.createRelationshipTo(hb, sj);
    		hb.createRelationshipTo(n1, xj);
    		
    		Node zj = db.createNode(fh);
    		zj.setProperty("name", "农业银行浙江分行");
    		n1.createRelationshipTo(zj, sj);
    		zj.createRelationshipTo(n1, xj);
    	}
    	
    	/**
    	 * 初始化工商银行分行数据
    	 */
    	static void init3(GraphDatabaseService db)throws Exception
    	{
    		Node n1 = db.getNodeById(2);
    		
    		Node gd = db.createNode(fh);
    		gd.setProperty("name", "工商银行广东分行");
    		n1.createRelationshipTo(gd, sj);
    		gd.createRelationshipTo(n1, xj);
    		
    		Node hn = db.createNode(fh);
    		hn.setProperty("name", "工商银行湖南分行");
    		n1.createRelationshipTo(hn, sj);
    		hn.createRelationshipTo(n1, xj);
    		
    		Node hb = db.createNode(fh);
    		hb.setProperty("name", "工商银行湖北分行");
    		n1.createRelationshipTo(hb, sj);
    		hb.createRelationshipTo(n1, xj);
    	}
    	
    	/**
    	 * 初始化农业银行广东分行下面的支行数据
    	 */
    	static void init4(GraphDatabaseService db)throws Exception
    	{
    		Node n1 = db.getNodeById(3);
    		
    		Node th = db.createNode(zh);
    		th.setProperty("name", "农业银行天河支行营业部");
    		n1.createRelationshipTo(th, sj);
    		th.createRelationshipTo(n1, xj);
    		
    		Node yt = db.createNode(zh);
    		yt.setProperty("name", "农业银行燕塘支行");
    		n1.createRelationshipTo(yt, sj);
    		yt.createRelationshipTo(n1, xj);
    		
    		Node thb = db.createNode(zh);
    		thb.setProperty("name", "农业银行天河北路支行");
    		n1.createRelationshipTo(thb, sj);
    		thb.createRelationshipTo(n1, xj);
    		
    		Node sp = db.createNode(zh);
    		sp.setProperty("name", "农业银行石牌东路支行");
    		n1.createRelationshipTo(sp, sj);
    		sp.createRelationshipTo(n1, xj);
    		
    		Node hy = db.createNode(zh);
    		hy.setProperty("name", "农业银行华苑支行");
    		n1.createRelationshipTo(hy, sj);
    		hy.createRelationshipTo(n1, xj);
    	}
    	
    	/**
    	 * start a=node(13) MATCH (a)<-[:SJ*1..3]-(b) return a,b (往上找三级，一共四级)
    	 * start a=node(1) MATCH (a)-[:SJ*1..3]->(b) return a,b (往下找三级，一共四级)
    	 */
    	public static void main(String[] args) throws Exception
    	{
    		GraphDatabaseService db = new GraphDatabaseFactory().newEmbeddedDatabase("/home/admin/db/neo4j");
    		
    		Transaction tx = db.beginTx();
    		init1(db);
    		init2(db);
    		init3(db);
    		init4(db);
    		tx.success();
    		tx.close();
    	}
    }

这里数据的路径是：/home/admin/db/neo4j

cd neo4j-community-2.2.3/conf

vim neo4j-server.properties 文件，把数据库目录改为上面的路径，然后，重启neo4j

访问

http://127.0.0.1:7474

输入默认的用户名/密码 neo4j/neo4j

然后，修改默认密码

即可查询

下面给几个查询语句

查询所有：match a return a

查询所有标签为'分行'的数据 match (a:分行) return a

start a=node(1) MATCH (a)-\[:SJ\*1..3\]->(b) return a,b (从node id=1开始，往下找三级，一共四级)