Neo4j的索引沒有找到節點

我試圖按照文檔和我結束了這段代碼爲Neo4j的1.8：Neo4j的索引沒有找到節點

graphDB = new GraphDatabaseFactory() 
      .newEmbeddedDatabaseBuilder(BASE_FOLDER + NEO4J_PATH) 
      .newGraphDatabase(); 

registerShutdownHook(); 

//Check if there are any indexes 
System.out.println(Arrays.toString(graphDB.index().nodeIndexNames())); 
Index<Node> testIndex = graphDB.index().forNodes("test"); 

Transaction tx = graphDB.beginTx(); 
try { 
    String nameKey = "name"; 
    String nameValue = "Gevorg"; 

    //The following 3 lines will be commented out 
    //when I run the program the second time 
    Node me = graphDB.createNode(); 
    me.setProperty(nameKey, nameValue); 
    testIndex.add(me, nameKey, nameValue); 

    Node meAgain = testIndex.get(nameKey, nameValue).getSingle(); 
    System.out.println(meAgain.getProperty(nameKey)); 

} finally { 
    tx.finish(); 
}

這將打印以下預期：

[] //There is no index at the very beginning 
Gevorg

後，程序終止，我評論了節點/索引的創建，然後再次運行該程序以觸發NullPointerException（meAgain爲null）。由於程序首先打印[test]，但是Node meAgain = testIndex.get(nameKey, nameValue).getSingle();未能檢索到節點，因此索引被正確檢索。我嘗試使用和不使用交易。我究竟做錯了什麼？？

來源

2012-10-05 Gevorg

你需要調用tx.finish

tx.success()

HTH

/彼得

之前標記您的Tx一樣成功，

來源

2012-10-05 04:32:12

Neo4j的索引沒有找到節點

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