easyexcel/src/main/java/com/alibaba/excel/util/WorkBookUtil.java

package com.alibaba.excel.util;

import com.alibaba.excel.support.ExcelTypeEnum;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.poifs.filesystem.POIFSFileSystem;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.streaming.SXSSFWorkbook;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

import java.io.IOException;
import java.io.InputStream;

import static com.alibaba.excel.util.StyleUtil.buildSheetStyle;

/**
 * 
 * @author jipengfei
 */
public class WorkBookUtil {

    public static Workbook createWorkBook(InputStream templateInputStream, ExcelTypeEnum excelType) throws IOException {
        Workbook workbook;
        if (ExcelTypeEnum.XLS.equals(excelType)) {
            workbook = (templateInputStream == null) ? new HSSFWorkbook() : new HSSFWorkbook(
                new POIFSFileSystem(templateInputStream));
        } else {
            workbook = (templateInputStream == null) ? new SXSSFWorkbook(500) : new SXSSFWorkbook(
                new XSSFWorkbook(templateInputStream));
        }
        return workbook;
    }

    public static Sheet createOrGetSheet(Workbook workbook, com.alibaba.excel.metadata.Sheet sheet) {
        Sheet sheet1 = null;
        try {
            try {
                sheet1 = workbook.getSheetAt(sheet.getSheetNo()-1);
            } catch (Exception e) {
            }
            if (null == sheet1) {
                sheet1 = createSheet(workbook, sheet);
                buildSheetStyle(sheet1,sheet.getColumnWidthMap());
            }
        } catch (Exception e) {
            throw new RuntimeException("constructCurrentSheet error", e);
        }
        return sheet1;
    }

    public static Sheet createSheet(Workbook workbook, com.alibaba.excel.metadata.Sheet sheet) {
        return workbook.createSheet(sheet.getSheetName() != null ? sheet.getSheetName() : sheet.getSheetNo() + "");
    }

    public static Row createRow(Sheet sheet, int rowNum) {
        return sheet.createRow(rowNum);
    }

    public static Cell createCell(Row row, int colNum, CellStyle cellStyle, String cellValue) {
        return createCell(row, colNum, cellStyle, cellValue, false);
    }

    public static Cell createCell(Row row, int colNum, CellStyle cellStyle, Object cellValue, Boolean isNum) {
        Cell cell = row.createCell(colNum);
        cell.setCellStyle(cellStyle);
        if (null != cellValue) {
            if (isNum) {
                cell.setCellValue(Double.parseDouble(cellValue.toString()));
            } else {
                cell.setCellValue(cellValue.toString());
            }
        }
        return cell;
    }

}