POI Jar包导出excel问题：maximum number of fonts was exceeded

这个错误是由于导出的数据量变大，多次创建字体样式而导致的；数据量小的时候不会报错。

所以解决办法就是把字体样式的创建、设置放到循环外面，循环调用就可以了。

具体代码如下：

 

Wrong :

for (int i = 0; i < 10000; i++) {

Row row = sheet.createRow(i);

Cell cell = row.createCell((short) 0);

CellStyle style = workbook.createCellStyle();

Font font = workbook.createFont();

font.setBoldweight(Font.BOLDWEIGHT_BOLD);

style.setFont(font);

cell.setCellStyle(style);

}
Correct:
<span style="color:#ff0000;">CellStyle style = workbook.createCellStyle();

Font font = workbook.createFont();

font.setBoldweight(Font.BOLDWEIGHT_BOLD);

style.setFont(font);

for (int i = 0; i < 10000; i++) {

Row row = sheet.createRow(i);

Cell cell = row.createCell((short) 0);

cell.setCellStyle(style);
</span>
}

Note : LOC of creating fonts is inside the loop , because when you are writing the records to the row.there is no need of keeping the font creation in loop , better move it outside the loop and try it . Sure popup message will not come in case of large datas populated in the worksheet .