我无法使用我的 java 代码更新 Excel 文件 (.xlsx)。你能告诉我我在哪里犯错吗？它抛出一个NullPointerException. 使用 POI Apache jars.Using Office 2016 for Excel
public class test_extra1 {
public static void main(String[] args) throws Exception {
//excel code
File src=new File("C:\\test.xlsx");
FileInputStream fis=new FileInputStream(src);
XSSFWorkbook wb=new XSSFWorkbook(fis);
XSSFSheet sh1= wb.getSheetAt(0);
String[] field_name = {"field1","field2"};
String isChecked ="Checked",temp;
int i;
for(i=0;i<2;i++){
System.out.println(i);
System.out.println("Checkbox not checked--"+isChecked);
temp = field_name[i];
System.out.println("temp----"+temp);
//error comes at below line
sh1.getRow(i+1).getCell(i+3).setCellValue("No");
sh1.getRow(i+1).createCell(i+3).setCellValue("No");
sh1.getRow(i+1).createCell(i+2).setCellValue(temp);
}
FileOutputStream fout=new FileOutputStream(new File("C:\\test1.xlsx"));
wb.write(fout);
fout.close();
}
}