在java中将String转换为数组

Question

以下是我的 Java 代码。我正在传递一个 CSV 文件并读取记录。我想用“，”分割记录并将其存储到一个数组中。我不知道该怎么做。如果有人可以给我一个想法。我对 Java 还很陌生。

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;

public class parser 
{
    public static void main(String[] args) throws IOException 
    {
        FileReader fileReader = new FileReader(new File("//Users//Desktop//npi.csv"));
        BufferedReader br = new BufferedReader(fileReader);
        String line = null;
        //String[] value = line.split(",");

        /*ArrayList list = new ArrayList(Arrays.asList(line));
        System.out.println(list);*/
        int count = 0;
        while((line = br.readLine()) != null)
        {
            for(int i=0; i < line.length();i++)
            {

            }
            count ++;
            System.out.println("Record Count : "+count);
            System.out.println(line);
        }

    }
}

CSV 文件中的字符串示例

"1234567","1","","","","ALI","唐纳森","","DR.","","O.D.","",""," ","","","","","","","140-6002 SIT RD","STE A","EVANSVILLE","IN","8418996408","US","6013857469","9586771232","140-6002 SIT RD","SUITE 一个","埃文斯维尔","IN","770155917","美国","6969551228","2403884068","04/13/2003","02/21/2018","",""," ","M","","","","","","142K01234Z","5376UD","IN","Y","","","",""," ","","","","","","","","","","","","","","","","", "","","","","","","","","","","","","","","","","" ,"","","","","","","","","","","","","","","",""," ","","980230944","03","IN","","WR09447","01","IN","","12532T","02","IN","GROUP" ,"245699532","08","IN","","3HDPTO","09","IN","个人","","","","","","", "","","","","","","","","","","","","","","","","" ,"","","","","","","","","","","","","","","",""," ","","","","","","","","","","","","","","","","", "","","","","","","","","","","","","","","","","" ,"","","","","","","","","","","","","","","",""," ","","","","","","","","","","","","","","","","", "","","","","","","","","","","","","","","","","" ,"","","","","","","","","","","","","","","",""," ","","","","","","","","","","","","","","","","", "","","","","","","","","","","","","","","","","" ，““，““，““，““，““，““，““，“X”，””，””，” ","","","","","","","","","","","","","","","","", "",""

Answer 1

您已使用Arrays.asList(line)，但您应该使用Arrays.asList(value)。还注释了while 循环内的代码位置。

List 是一个接口，ArrayList 是一个实现。您不需要对象的实例类型来使用数据。只需使用一个接口。您还应该知道对接口进行编码 是 Java 中的最佳实践，也是一般 OOP 的原则之一。

对于单行，它需要List<String>，要保存这些行，您应该使用另一个列表List<List<String>>。您可以逐行实例化并向其添加列表。

Answer 2

使用“，”作为分隔符分割每一行：

String[] records = line.split(",");

Answer 3

在您的代码中有一个错误：您试图拆分 null 的字符串。将其移至 line 指向实际 String 对象的 while 循环中。

您想在"," 处拆分字符串，但我猜您还想删除"，如果它是第一个或最后一个字符。

这可以使用String.split(String regex)：

String[] split = x.split("(\",\"|\\A\"|\"\\z)");

这个正则表达式在任何地方都匹配","，在字符串的开头/结尾匹配"。如果输入以引号开头，则结果数组以空字符串开头。

请注意，使用输出数组要容易得多

System.out.println( Arrays.toString(myArray) );

Answer 4

首先定义一个您想要存储所有单词的列表：

List<String> list = new ArrayList<String>();

您的while 循环中不需要for 循环。摆脱它并改用以下方法：

//Remove quotes. I think you wouldn't need them.
line = line.replace("\"", "");
//Now get the words which are separated by a comma
String[] words = line.split(",");
//Now add all the words to the main list
Collections.addAll(list, words);