POI 产生巨大 EXCEL 报表

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SXSSF is a brand new contribution and some features were added after it was first introduced in POI 3.8-beta3. Users are advised to try the latest build from trunk. Instructions how to build are here

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import junit.framework.Assert;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.ss.util.CellReference;
import org.apache.poi.xssf.streaming.SXSSFWorkbook;
  public static void main(String[] args) throws Throwable { Workbook wb = new SXSSFWorkbook(100); // keep 100 rows in memory, exceeding rows will be flushed to disk Sheet sh = wb.createSheet(); for(int rownum = 0; rownum < 1000; rownum++){ Row row = sh.createRow(rownum); for(int cellnum = 0; cellnum < 10; cellnum++){ Cell cell = row.createCell(cellnum); String address = new CellReference(cell).formatAsString(); cell.setCellValue(address); }
  }
  // Rows with rownum < 900 are flushed and not accessible for(int rownum = 0; rownum < 900; rownum++){ Assert.assertNull(sh.getRow(rownum)); }
  // ther last 100 rows are still in memory for(int rownum = 900; rownum < 1000; rownum++){ Assert.assertNotNull(sh.getRow(rownum)); } FileOutputStream out = new FileOutputStream("/temp/sxssf.xlsx"); wb.write(out); out.close(); }

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Workbook wb = new SXSSFWorkbook(100); // keep 100 rows in memory, exceeding rows will be flushed to disk