Question

如何使用CsvWriter格式的csv编写整数数组和字符串数组？

import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map.Entry;
import java.util.Set;
import au.com.bytecode.opencsv.CSVReader;
import au.com.bytecode.opencsv.CSVWriter;

public class ArrayHash3
{
    public static void main(String args[]) throws IOException
    {
        int[] WorkingDay = new int[13];
        int i = 0;
        String[] arrString = null;
        int[] arrInt = null;
        String[] Name = new String[13];     
        String file="C:\\Users\\Dhananjay Kumar\\Empdetail\\Detail.csv";
        HashMap<String[],int[]> hashfunc=new HashMap<String[],int[]>();
        CSVReader reader=new CSVReader(new FileReader(file));
        String[] read;
        while((read = reader.readNext()) !=null)
        {
            WorkingDay[i]=Integer.parseInt(read[2]);
            Name[i]=read[0];
            i++;            
        }

        hashfunc.put(Name,WorkingDay);
        hashfunc.get(Name);
        Set<Entry<String[], int[]>> entrySet = hashfunc.entrySet();     
        for (Entry entry : entrySet)
        {
            arrInt = (int[]) entry.getValue(); 
            arrString = (String[]) entry.getKey();              

            for(int j=0; j<arrInt.length; j++)
            {
                System.out.println(arrString[j]+":"+arrInt[j]);
            }
        }

        String File1 = "C:\\Users\\Kumar\\Empdetail\\Detail6.csv";
        CSVWriter fw = new CSVWriter(new FileWriter(File1, true));      
        fw.writeAll(arrString+","+arrInt);
        fw.close();

    }
}

Answer 1

如果您只想写出一些带分隔符的数组，则不需要CSVWriter。

查看https://docs.oracle.com/javase/8/docs/api/java/util/StringJoiner.html

List<Integer> numbers = Arrays.asList(1, 2, 3, 4);
String commaSeparatedNumbers = numbers.stream()
                                      .map(i -> i.toString())
                                      .collect(Collectors.joining(","));

CSVWriter用于整数数组

1 个答案: