如何在java中使用密码加载CSV文件? [英] How to load CSV file with cypher in java?

问题描述

我是密码的新手.我想在 java 中使用密码加载 csv.我用谷歌搜索并找到了以下内容

I am new to cypher. I want to load a csv using cypher in java. I googled and found the following piece

LOAD CSV WITH HEADERS FROM "http://neo4j.com/docs/2.3.1/csv/import/movies.csv" AS csvLine
MERGE (country:Country { name: csvLine.country })
.....

如何使用此加载 csv 查询到 java 代码中.我试过这样的事情.

How to use this load csv query into java code. I tried something like this.

import java.io.File;
import java.io.IOException;
import java.util.Map;
import java.util.Map.Entry;

import javax.naming.spi.DirStateFactory.Result;

import org.neo4j.cypher.javacompat.ExecutionEngine;
import org.neo4j.cypher.javacompat.ExecutionResult;
import org.neo4j.graphdb.Direction;
import org.neo4j.graphdb.GraphDatabaseService;
import org.neo4j.graphdb.Node;
import org.neo4j.graphdb.Relationship;
import org.neo4j.graphdb.RelationshipType;
import org.neo4j.graphdb.Transaction;
import org.neo4j.graphdb.factory.GraphDatabaseFactory;
import org.neo4j.kernel.impl.util.FileUtils;
public class test_new {


private static final String DB_PATH = "C:...../default.graphdb";
public static void main( final String[] args ) throws IOException
{
    GraphDatabaseService db = new GraphDatabaseFactory().newEmbeddedDatabase( DB_PATH );



    Transaction tx1 = db.beginTx();
    try{

        ExecutionEngine engine = new ExecutionEngine(db);
      ExecutionResult result = engine.execute("LOAD CSV WITH HEADERS FROM "C:/..../Mock_data.csv" AS csvLine ");

        tx1.success();
    } finally {
        tx1.close();

    }
    db.shutdown();
}

}

但我不确定这条线.

 ExecutionResult result = engine.execute("LOAD CSV WITH HEADERS FROM "C:/..../Mock_data.csv" AS csvLine ");

它抛出语法错误.

Exception in thread "main" java.lang.Error: Unresolved compilation problems: 
Syntax error, insert ")" to complete MethodInvocation
Syntax error, insert ";" to complete LocalVariableDeclarationStatement

我自己也不知道语法结构.如何加载csv路径?

I don't know the syntax construction myself. How to load the csv path?

推荐答案

纠正Java语法错误，需要在字符串中间转义双引号；否则看起来你的字符串文字在路径周围的引号处结束:

To correct the Java syntax error, you need to escape double quotes in the middle of the string; otherwise it looks like your string literal finishes at the quote around the path:

"LOAD CSV WITH HEADERS FROM "C:/..../Mock_data.csv" AS csvLine "

这篇关于如何在java中使用密码加载CSV文件?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！