从java导入xlsx批量数据
我在excel表格中有100万条数据记录。客户要求将此文件转换为csv格式 我尝试了以下代码集从java导入xlsx批量数据,java,excel,Java,Excel,我在excel表格中有100万条数据记录。客户要求将此文件转换为csv格式 我尝试了以下代码集 File src = new File("C:\\test.xlsx") File dest = new File("C:\\test.csv") src.renameTo(dest); 这是转换文件。但是当我打开时,打开文件时会出错 另外,我尝试了以下代码 class XlstoCSV { public static void main(String[] args) {
File src = new File("C:\\test.xlsx")
File dest = new File("C:\\test.csv")
src.renameTo(dest);
这是转换文件。但是当我打开时,打开文件时会出错
另外,我尝试了以下代码
class XlstoCSV
{
public static void main(String[] args)
{
File inputFile = new File("C:\test.xls");
File outputFile = new File("C:\output.csv");
// For storing data into CSV files
StringBuffer data = new StringBuffer();
try
{
FileOutputStream fos = new FileOutputStream(outputFile);
// Get the workbook object for XLS file
HSSFWorkbook workbook = new HSSFWorkbook(new FileInputStream(inputFile));
// Get first sheet from the workbook
HSSFSheet sheet = workbook.getSheetAt(0);
Cell cell;
Row row;
// Iterate through each rows from first sheet
Iterator<Row> rowIterator = sheet.iterator();
while (rowIterator.hasNext())
{
row = rowIterator.next();
// For each row, iterate through each columns
Iterator<Cell> cellIterator = row.cellIterator();
while (cellIterator.hasNext())
{
cell = cellIterator.next();
switch (cell.getCellType())
{
case Cell.CELL_TYPE_BOOLEAN:
data.append(cell.getBooleanCellValue() + ",");
break;
case Cell.CELL_TYPE_NUMERIC:
data.append(cell.getNumericCellValue() + ",");
break;
case Cell.CELL_TYPE_STRING:
data.append(cell.getStringCellValue() + ",");
break;
case Cell.CELL_TYPE_BLANK:
data.append("" + ",");
break;
default:
data.append(cell + ",");
}
data.append('\n');
}
}
fos.write(data.toString().getBytes());
fos.close();
}
catch (FileNotFoundException e)
{
e.printStackTrace();
}
catch (IOException e)
{
e.printStackTrace();
}
}
我在上面一行中得到堆内存错误。我不知道如何使用java进行批量数据上传。我甚至尝试了ApachePOIJAR代码。但该代码也在失败
有人能帮我吗?最简单的方法(假设代码在较小的文件上工作):增加JVM使用的内存
或者,您可以逐行写入文件:
Path outputFile = Paths.get("C:\output.csv");
HSSFWorkbook workbook = new HSSFWorkbook(new FileInputStream(inputFile));
HSSFSheet sheet = workbook.getSheetAt(0);
for (Row row : sheet) {
List<String> csv = new StringBuilder();
for (Cell cell : row) {
//add the logic with csv.add(cell.getXXXValue()); etc., no comma here
}
String csvRow = String.join(",", csv) + "\n";
Files.write(outputFile, csvRow.getBytes(UTF_8), StandardOpenOption.APPEND);
}
Path outputFile=Path.get(“C:\output.csv”);
HSSFWorkbook=新的HSSFWorkbook(新文件InputStream(inputFile));
HSSFSheet sheet=工作簿。getSheetAt(0);
用于(行:页){
List csv=新的StringBuilder();
用于(单元格:行){
//使用csv.add(cell.getXXXValue())等添加逻辑,此处不使用逗号
}
String csvRow=String.join(“,”,csv)+“\n”;
write(outputFile、csvRow.getBytes(UTF_8)、StandardOpenOption.APPEND);
}
用于导入Excel文件并在基于磁盘的文件数据库中缓存行。有没有不在Excel中打开文件并“另存为”的原因csv?@assylias谢谢您刚刚保存的MyTime是服务器上正在动态更新的文件吗?该文件位于服务器计算机上,客户端希望将其转换为csv,我们必须将该文件移动到客户端路径,以便客户端可以从there@madhunatarajan在这里,您会发现ApachePOI也不是什么新东西工作在那里,我也发现它失败了
Path outputFile = Paths.get("C:\output.csv");
HSSFWorkbook workbook = new HSSFWorkbook(new FileInputStream(inputFile));
HSSFSheet sheet = workbook.getSheetAt(0);
for (Row row : sheet) {
List<String> csv = new StringBuilder();
for (Cell cell : row) {
//add the logic with csv.add(cell.getXXXValue()); etc., no comma here
}
String csvRow = String.join(",", csv) + "\n";
Files.write(outputFile, csvRow.getBytes(UTF_8), StandardOpenOption.APPEND);
}