使用 SXSSF POI 编写大型 Excel 工作表
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【中文标题】使用 SXSSF POI 编写大型 Excel 工作表【英文标题】：Writing large Excel sheet using SXSSF POI 【发布时间】：2015-09-22 12:40:11 【问题描述】：我正在使用 POI () 的流式工作表编写一个大型 Excel 表（超过一百万条记录），但我得到了java.lang.OutOfMemoryError: Java heap space。这是我的代码：
public void exportExcel()
try
SXSSFWorkbook workbook = new SXSSFWorkbook();
Sheet sheet = workbook.createSheet();
List<Oject> list = dao.getList();
Cell cell = null;
if (!list.isEmpty())
Row row = sheet.createRow(0);
cell = row.createCell(0);
cell.setCellValue("s1");
cell = row.createCell(1);
cell.setCellValue("s2");
cell = row.createCell(2);
cell.setCellValue("s3");
cell = row.createCell(3);
cell.setCellValue("s4");
cell = row.createCell(4);
cell.setCellValue("s5");
cell = row.createCell(5);
cell.setCellValue("s6");
cell = row.createCell(6);
cell.setCellValue("s7");
cell = row.createCell(7);
cell.setCellValue("s8");
cell = row.createCell(8);
cell.setCellValue("s9");
cell = row.createCell(9);
cell.setCellValue("s10");
cell = row.createCell(10);
cell.setCellValue("s11");
cell = row.createCell(11);
cell.setCellValue("s12");
cell = row.createCell(12);
cell.setCellValue("s13");
cell = row.createCell(13);
cell.setCellValue("s14");
cell = row.createCell(14);
cell.setCellValue("s15");
cell = row.createCell(15);
cell.setCellValue("s16");
cell = row.createCell(16);
cell.setCellValue("s17");
cell = row.createCell(17);
cell.setCellValue("s18");
cell = row.createCell(18);
cell.setCellValue("s19");
cell = row.createCell(19);
cell.setCellValue("s20");
cell = row.createCell(20);
cell.setCellValue("s21");
cell = row.createCell(21);
cell.setCellValue("s22");
cell = row.createCell(22);
cell.setCellValue("s23");
cell = row.createCell(23);
cell.setCellValue("s24");
cell = row.createCell(24);
cell.setCellValue("s25");
cell = row.createCell(25);
cell.setCellValue("s26");
cell = row.createCell(26);
cell.setCellValue("s27");
cell = row.createCell(27);
cell.setCellValue("s28");
cell = row.createCell(28);
cell.setCellValue("s29");
cell = row.createCell(29);
cell.setCellValue("s30");
cell = row.createCell(30);
cell.setCellValue("s31");
cell = row.createCell(31);
cell.setCellValue("s32");
cell = row.createCell(32);
cell.setCellValue("s33");
cell = row.createCell(33);
cell.setCellValue("s34");
cell = row.createCell(34);
cell.setCellValue("s35");
cell = row.createCell(35);
cell.setCellValue("s36");
cell = row.createCell(36);
cell.setCellValue("s37");
for (int i = 0; i < list.size(); i++)
row = sheet.createRow(i + 1);
cell = row.createCell(0);
if (list.get(i).getOne == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getOne);
cell = row.createCell(1);
if (list.get(i).getTwo() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getTwo());
cell = row.createCell(2);
if (list.get(i).getThree() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getThree());
cell = row.createCell(3);
if (list.get(i).getFour() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getFour().toString());
cell = row.createCell(4);
if (list.get(i).getFive() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getFive());
cell = row.createCell(5);
if (list.get(i).getSix() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getSix());
cell = row.createCell(6);
if (list.get(i).getSeven() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getSeven());
cell = row.createCell(7);
if (list.get(i).getEight() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getEight());
cell = row.createCell(8);
if (list.get(i).getNine() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getNine());
cell = row.createCell(9);
if (list.get(i).getTen() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getTen().toString());
cell = row.createCell(10);
if (list.get(i).getD() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getD());
cell = row.createCell(11);
if (list.get(i).getF() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getF().toString());
cell = row.createCell(12);
if (list.get(i).getV() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getV().toString());
cell = row.createCell(13);
if (list.get(i).getVa() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getVa().toString());
cell = row.createCell(14);
if (list.get(i).getFo() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getFo().toString());
cell = row.createCell(15);
if (list.get(i).getVar() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getVar().toString());
cell = row.createCell(16);
if (list.get(i).getVarm() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getVarm().toString());
cell = row.createCell(17);
if (list.get(i).getFor() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getFor().toString());
cell = row.createCell(18);
if (list.get(i).getVarp() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getVarp().toString());
cell = row.createCell(19);
if (list.get(i).getVau() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getVau().toString());
cell = row.createCell(20);
if (list.get(i).getFoi() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getFoi().toString());
cell = row.createCell(21);
if (list.get(i).getVaro() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getVaro());
cell = row.createCell(22);
if (list.get(i).getVo() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getvo().toString());
cell = row.createCell(23);
if (list.get(i).getF5() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getF5().toString());
cell = row.createCell(24);
if (list.get(i).getV5() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getV5().toString());
cell = row.createCell(25);
if (list.get(i).getVm5() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getVm5().toString());
cell = row.createCell(26);
if (list.get(i).getDo() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getDo().toString());
cell = row.createCell(27);
if (list.get(i).getDmow() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getDmow().toString());
cell = row.createCell(28);
if (list.get(i).getCut() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getCut());
cell = row.createCell(29);
if (list.get(i).getDre() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getDre().toString());
cell = row.createCell(30);
if (list.get(i).getCli() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getCli());
cell = row.createCell(31);
if (list.get(i).getDn() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getDn().toString());
cell = row.createCell(32);
if (list.get(i).getCod() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getCod());
cell = row.createCell(33);
if (list.get(i).getCk() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getCk());
cell = row.createCell(34);
if (list.get(i).getRem() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getRem().toString());
cell = row.createCell(35);
if (list.get(i).getPs() == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getPs().toString());
cell = row.createCell(36);
if (list.get(i).getTyp) == null)
cell.setCellValue("");
else
cell.setCellValue(list.get(i).getTyp().toString());
FacesContext facesContext = FacesContext.getCurrentInstance();
ExternalContext externalContext = facesContext.getExternalContext()
externalContext.setResponseContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
externalContext.setResponseHeader("Content-Disposition", "attachment; filename=\"Lim_" + new Date().toString() + ".xlsx\"");
workbook.write(externalContext.getResponseOutputStream());
facesContext.responseComplete();
workbook.dispose();
catch (Exception e)
FacesContext.getCurrentInstance().addMessage(null, new FacesMessage(FacesMessage.SEVERITY_ERROR, "Error", null));
e.printStackTrace();
由于列表的大小不同，我需要了解问题，我的堆大小是 512m
【问题讨论】：
你在用eclipse吗。
你迭代了几十个方法，你应该阅读“push and pop”和你的变量的生命周期。为什么你要静态访问所有 createCell() 方法而不是 createCell(i);
我正在使用 netbeans，我知道单元格的数量，所以我不需要遍历它们
【参考方案1】：
当您使用new SXSSFWorkbook(); 创建流式工作簿时，您会隐式指定无限制 行访问权限。这通常不是你想要写的。我建议在构造函数中添加一个整数参数，例如
SXSSFWorkbook workbook = new SXSSFWorkbook(100);
这应该会大大减少内存消耗。您甚至可以使用1 作为数字，只要您只按顺序写入行即可。
【讨论】：
还是同样的问题，知道我做错了什么吗？ 尝试从您的 JSF 代码中提取 Excel 编写代码并在相同的内存限制下直接运行它。如果这样可行，您可能需要更改您的 JSF 配置或代码，因为 JSF 很可能会尝试将您的大型工作表存储在内存中，以便它可以在发送之前设置一个大小标题。以上是关于使用 SXSSF POI 编写大型 Excel 工作表的主要内容，如果未能解决你的问题，请参考以下文章
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