在导出时注册registerWriteHandler(new CustomCellWriteHandler())

/**

* @author jamin

* @date 2020/7/29 11:28

* 设置自适应列宽

*/

public class CustomCellWriteHandler extends AbstractColumnWidthStyleStrategy {

private Map> CACHE = new HashMap<>();

@Override

protected void setColumnWidth(WriteSheetHolder writeSheetHolder, List cellDataList, Cell cell, Head head, Integer integer, Boolean isHead) {

boolean needSetWidth = isHead || !CollectionUtils.isEmpty(cellDataList);

if (needSetWidth) {

Map maxColumnWidthMap = CACHE.get(writeSheetHolder.getSheetNo());

if (maxColumnWidthMap == null) {

maxColumnWidthMap = new HashMap<>();

CACHE.put(writeSheetHolder.getSheetNo(), maxColumnWidthMap);

}

Integer columnWidth = this.dataLength(cellDataList, cell, isHead);

if (columnWidth >= 0) {

if (columnWidth > 255) {

columnWidth = 255;

}

Integer maxColumnWidth = maxColumnWidthMap.get(cell.getColumnIndex());

if (maxColumnWidth == null || columnWidth > maxColumnWidth) {

maxColumnWidthMap.put(cell.getColumnIndex(), columnWidth);

writeSheetHolder.getSheet().setColumnWidth(cell.getColumnIndex(), columnWidth * 256);

}

}

}

}

private Integer dataLength(List cellDataList, Cell cell, Boolean isHead) {

if (isHead) {

return cell.getStringCellValue().getBytes().length;

} else {

CellData cellData = cellDataList.get(0);

CellDataTypeEnum type = cellData.getType();

if (type == null) {

return -1;

} else {

switch (type) {

case STRING:

return cellData.getStringValue().getBytes().length;

case BOOLEAN:

return cellData.getBooleanValue().toString().getBytes().length;

case NUMBER:

return cellData.getNumberValue().toString().getBytes().length;

default:

return -1;

}

}

}

}

}