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neo4j简单操作

程序员文章站 2022-06-08 16:53:37
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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。
我已在电脑上安装并启动了neo4j,简单连接测试下


/**
 * 關係枚舉
 * @author zhangk
 *
 */
public enum FirstRelationshipTypes implements RelationshipType {
    FIRST
}


    /**
     * 獲得數據庫管理類
     * @param graphPath
     * @return
     */
    public static GraphDatabaseService getDbService(String graphPath) {
        return new EmbeddedGraphDatabase(graphPath);
    }

    public static void createData(String graphPath) {
        GraphDatabaseService db = getDbService(graphPath);
        registerShutdownHook(db);  
        Transaction tx = db.beginTx();  
        try {
            Node firstNode = db.createNode();
            Node secondNode = db.createNode();
            firstNode.setProperty("name", "zhang");
            secondNode.setProperty("name", "kai");
            // 連接2個節點
            firstNode.createRelationshipTo(secondNode, FirstRelationshipTypes.FIRST);
            String zhangkai = firstNode.getProperty("name") + " " + secondNode.getProperty("name");
            System.out.println(zhangkai);
            //Relationship relationship = firstNode.getSingleRelationship(FirstRelationshipTypes.FIRST, Direction.OUTGOING);
            Iterable<Relationship> rls = firstNode.getRelationships();
            for (Relationship relationship : rls) {
                System.out.println(relationship.getId());  
                System.out.println(relationship.getEndNode().getProperty("name"));  
                System.out.println(relationship.getStartNode().getProperty("name"));  
                relationship.delete(); 
            }
             
//            firstNode.delete();  
//            secondNode.delete();  
            tx.success();  
        } catch(Exception e) {
            tx.finish();
        }
        System.out.println("Shutting down database ...");  
        db.shutdown();
    }


    /**
     *  实时监测服务状态
     *  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 example before it's completed)  
     *  @param graphDb
     */
    private static void registerShutdownHook(final GraphDatabaseService graphDb) {  

        Runtime.getRuntime().addShutdownHook(new Thread() {  
            @Override  
            public void run() {  
                graphDb.shutdown();  
            }  
        });  
    }  


    private static final String GPATH = "graph.db"; // 數據庫地址

    public static void main(String[] args) {
        createData(GPATH);
    }