java - 使用java apache poi在列CSV文件中断后获取字符串

Question

我正在使用此代码将 CSV 转换为 XLSX

try {
        String home = System.getProperty("user.home");
        File file = new File(home+"/Downloads/test.csv");
        File file1 = new File(home+"/Downloads/test1.xlsx");
        XSSFWorkbook workBook = new XSSFWorkbook();
        XSSFSheet sheet = workBook.createSheet("sheet1");
        String currentLine=null;
        int RowNum=0;
        BufferedReader br = new BufferedReader(new FileReader(file));
        while ((currentLine = br.readLine()) != null) {
            String str[] = currentLine.split(",");
            RowNum++;
            XSSFRow currentRow=sheet.createRow(RowNum);
            for(int i=0;i<str.length;i++){
                System.out.println(str[i]+"/n");
                currentRow.createCell(i).setCellValue(str[i]);
            }
        }

        FileOutputStream fileOutputStream =  new FileOutputStream(file1);
        workBook.write(fileOutputStream);
        fileOutputStream.close();
        System.out.println("Done");
    } catch (Exception ex) {
        System.out.println(ex.getMessage()+"Exception in try");
    }

CSV 文件中的一列使用此 str.length 换行另一行，它采用单独的单独行，我想采用整个列的值。

我想取整列值并将其写入 XLSX 文件。

标签： javaapache-poi

Answer 1

你似乎有一个CSV根据RFC4180。CSV格式的定义说明：

6. 包含换行符 (CRLF)、双引号和逗号的字段应该用双引号括起来。例如：

     "aaa","b CRLF
      bb","ccc" CRLF
      zzz,yyy,xxx
   

这比简单的 CSV 更复杂，并且不能简单地逐行读取，因为不是每个换行都意味着一条新记录。尝试查找支持 RFC4180 的 CSV 解析器。

opencsv就是这样。

例子：

CSV.csv：

Field1,Field2,Field3
123,This is test column.,345
678,"This is test column.
This is next line",910
123,This is test column.,345

代码：

import java.io.FileOutputStream;
import java.io.FileReader;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

import com.opencsv.CSVReader;

class ParseCSVToExcel {

 public static void main(String[] args) throws Exception {

  try (XSSFWorkbook workbook = new XSSFWorkbook(); 
       FileOutputStream out = new FileOutputStream("Excel.xlsx");
       FileReader in = new FileReader("CSV.csv")) { 

   CellStyle cellStyle = workbook.createCellStyle();
   cellStyle.setWrapText(true);

   Sheet sheet = workbook.createSheet("FromCSV");
   Row row = null;
   Cell cell = null;
   int r = 0;
   int maxC = 0;

   CSVReader reader = new CSVReader(in);
   String [] nextLine;
   while ((nextLine = reader.readNext()) != null) {
    row = sheet.createRow(r++);
    int c = 0;
    for (String field : nextLine) {
     cell = row.createCell(c++);
     cell.setCellValue(field);
     cell.setCellStyle(cellStyle);
    }
    if (c > maxC) maxC = c;
   }
   
   for (int c = 0; c < maxC; c++) {
    sheet.autoSizeColumn(c);
   }

   workbook.write(out);

  }
 }
}

结果：

---

使用Apache Commons CSV将是另一种可能性。

和上面一样CSV.csv。

代码：

import java.io.FileOutputStream;
import java.io.FileReader;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

import org.apache.commons.csv.CSVRecord;
import org.apache.commons.csv.CSVFormat;

class ParseCSVToExcelApacheCommonsCSV {

 public static void main(String[] args) throws Exception {

  try (XSSFWorkbook workbook = new XSSFWorkbook(); 
       FileOutputStream out = new FileOutputStream("Excel.xlsx");
       FileReader in = new FileReader("CSV.csv")) { 

   CellStyle cellStyle = workbook.createCellStyle();
   cellStyle.setWrapText(true);

   Sheet sheet = workbook.createSheet("FromCSV");
   Row row = null;
   Cell cell = null;
   int r = 0;
   int maxC = 0;

   for (CSVRecord record : CSVFormat.RFC4180.parse(in)) {
    row = sheet.createRow(r++);
    int c = 0;
    for (String field : record) {
     cell = row.createCell(c++);
     cell.setCellValue(field);
     cell.setCellStyle(cellStyle);
    }
    if (c > maxC) maxC = c;
   }
   
   for (int c = 0; c < maxC; c++) {
    sheet.autoSizeColumn(c);
   }

   workbook.write(out);

  }
 }
}

结果与上述相同。