Java读取,存写excel数据

前言所需jar包：

  
	      org.apache.poi  
	      poi  
	      3.10-FINAL  
	      
	      
	      org.apache.poi  
	      poi-ooxml  
	      3.10-FINAL  
	      
		
		    org.apache.commons
		    commons-collections4
		    4.1
		

读取excel文件内容，支持日期，数据，字符，公式，布尔

public class ExcelUtil {
	public static List readExcel(){
		List sheetPOs = new ArrayList<>();
		File file = new File("F:/students.xls");
		try{
	        String fileName = file.getName();
	        String extName = "."+fileName.substring(fileName.lastIndexOf(".") + 1);
			Workbook wb = null;
			if(".xls".equals(extName)){
				wb = new HSSFWorkbook(new FileInputStream(file));
			}else if(".xlsx".equals(extName)){
				wb = new XSSFWorkbook(new FileInputStream(file));
			}else{
				throw new IllegalArgumentException("Invalid excel version");
			}
			//解析sheet
			//获取sheet页签
			int sheetNum = wb.getNumberOfSheets();
			for(int i = 0 ; i < sheetNum ; i ++){
				Sheet sheet = wb.getSheetAt(i);
				Integer rowCount = sheet.getPhysicalNumberOfRows();
				List> dataList = new ArrayList<>();
				ExcelSheetPO sheetPO = new ExcelSheetPO();
				sheetPO.setSheetName(sheet.getSheetName());
				sheetPO.setDataList(dataList);
				int readRowCount = 0;
				if(rowCount == null || rowCount > sheet.getPhysicalNumberOfRows()){
					readRowCount = sheet.getPhysicalNumberOfRows();
				}else{
					readRowCount = rowCount;
				}
				//解析sheet行
				for(int j = sheet.getFirstRowNum(); j < readRowCount ; j ++){
					Row row = sheet.getRow(j);
					Integer columnCount = sheet.getRow(j).getPhysicalNumberOfCells();
					if(row == null){
						continue;
					}
					if(row.getFirstCellNum()< 0){
						continue;
					}
					int readColumnCount = 0;
					if(columnCount == null || columnCount > row.getLastCellNum()){
						readColumnCount = (int)row.getLastCellNum();
					}else{
						readColumnCount = columnCount;
					}
					List