Question

出于某种原因，虽然我已经下载了CSV文件，但我的程序无法读取它们。我的代码如下，它检查CSV文件是否存在。如果没有，则转到URL并下载并读取代码。但是，它总是重新下载代码，尽管它位于路径文件夹中。

 private void loadData(String path, String url) throws IOException{

    File f = new File(path);
    System.out.println("looking for path " + path);
    if(f.exists()) { 
        readSavedFile(path); //method to load data
    }
    else{
        System.out.println("Need to download from internet");
        downloadAndRead(url, path);
    }

}

此代码输出

寻找路径C：\ Users \ n_000 \ workspace \ Program \ GOOG.csv 需要从互联网上下载。寻找路径C：\ Users \ n_000 \ workspace \ Program \ CHK.csv 需要从互联网上下载。

我用来创建路径的代码是：

        String save = "filename"; //in program use this is the name of the stock eg GOOG or CHK
        Path currentRelativePath = Paths.get("");
        String savedFolder = currentRelativePath.toAbsolutePath().toString() + "\\";

        path = savedFolder+save+".csv";

Answer 1

它工作正常，我没有看到任何问题，我发布了我测试的代码，希望它可能有用。

import java.io.File;
import java.io.IOException;
import java.nio.file.Path;
import java.nio.file.Paths;

public class Test {

    public static void main(String ar[])
    {
        Test test=new Test();
    }
    public Test() 
    {   
        String save = "GOOG"; //in program use this is the name of the stock eg GOOG or CHK
        Path currentRelativePath = Paths.get("");
        String savedFolder = currentRelativePath.toAbsolutePath().toString() + "\\";
        String path = savedFolder+save+".csv";
        String url=null;

        try 
        {
            loadData(path,url);

        } catch (IOException e) 
        {
            e.printStackTrace();
        }
    }


    private  void loadData(String path, String url) throws IOException
    {    
        File f = new File(path);
        System.out.println("looking for path " + path);
        if(f.exists()) { 
            readSavedFile(path); //method to load data
        }
        else{
            System.out.println("Need to download from internet");
            downloadAndRead(url, path);
        }
    }
    public  void readSavedFile(String path)
    {
        System.out.println("Reading file");
    }

    public  void downloadAndRead(String url,String path)
    {
        System.out.println("Downloding file");
    }
}

Java - 无法找到并加载CSV文件

1 个答案: