poi操作excel

面向对象的思想，首先你要操作一个excel，进行excel的分析，获取整个excel，然后获取sheet，获取row，接下来用row获取col。这样就解决了哦。
接下来看几个重要代码块

 package com;import java.io.FileInputStream;import java.io.IOException;import java.io.InputStream;import java.util.ArrayList;import java.util.Iterator;import java.util.List;import org.apache.poi.hssf.usermodel.HSSFWorkbook;import org.apache.poi.ss.usermodel.Sheet;import org.apache.poi.ss.usermodel.Workbook;import org.apache.poi.xssf.usermodel.XSSFCell;import org.apache.poi.xssf.usermodel.XSSFRow;import org.apache.poi.xssf.usermodel.XSSFWorkbook;/** * Created by kcz on 2016/9/8. */public class Read {    public List<List<String>>list=new ArrayList<>();    public static int lastRowNum=0;    public static int lastCellNum=0;    public static void main(String[] args) {        new Read().read("E:\\ExcelTest\\data.xlsx");        System.out.println("-------------");        //readXml("d:\\data1.xls");    }    public  List<List<String>> read(String fileName) {        boolean isE2007 = false;    //判断是否是excel2007格式        if (fileName.endsWith("xlsx"))            isE2007 = true;        try {            InputStream input = new FileInputStream(fileName);  //建立输入流            Workbook wb = null;            //根据文件格式(2003或者2007)来初始化            if (isE2007)                wb = new XSSFWorkbook(input);            else                wb = new HSSFWorkbook(input);            for (int i = 0; i < wb.getNumberOfSheets(); i++) {//获取每个Sheet表                Sheet sheet = wb.getSheetAt(i);                int firstRowNum = sheet.getFirstRowNum();                lastRowNum = sheet.getLastRowNum();                for (int j = firstRowNum; j <= lastRowNum; j++) {                    XSSFRow rowIn = (XSSFRow) sheet.getRow(j);                    if(rowIn == null) {                        continue;                    }                    int firstCellNum = rowIn.getFirstCellNum();                     lastCellNum = rowIn.getLastCellNum();                    List<String>list1=new ArrayList<>();                    for (int k = firstCellNum; k <= lastCellNum; k++) {//              XSSFCell cellIn = rowIn.getCell((short) k);                        XSSFCell cellIn = rowIn.getCell(k);                        if(cellIn == null) {                            continue;                        }                        int cellType = cellIn.getCellType();                        if(XSSFCell.CELL_TYPE_STRING != cellType) {                            continue;                        }                        String cellValue = cellIn.getStringCellValue();                        if(cellValue == null) {                            continue;                        }                        list1.add(cellValue);                        //System.out.println(cellValue);                    }                    list.add(list1);                }            }            }catch (IOException ex) {            ex.printStackTrace();        }        Iterator iterator=  list.iterator();        while (iterator.hasNext()){            System.out.println(iterator.next());            System.out.println(lastCellNum);            System.out.println(lastRowNum);        }        return list;        }    }

package com;import java.io.*;import java.util.List;import org.apache.poi.ss.usermodel.Cell;import org.apache.poi.ss.usermodel.Row;import org.apache.poi.ss.usermodel.Sheet;import org.apache.poi.ss.usermodel.Workbook;import org.apache.poi.xssf.usermodel.XSSFWorkbook;/** * Created by kcz on 2016/9/8. */public class Write {    public static int lastRowNum=0;    public static int lastCellNum=0;    public static int bt = 0;    public static void main(String[] args) throws IOException {        new Write().outputExcelData();    }    public void outputExcelData() throws IOException {       Read read =new Read();       List<List<String>> lists = read.read("E:\\ExcelTest\\data.xlsx");     lastRowNum = read.lastRowNum ;     lastCellNum = read.lastCellNum ;        String fileName = "E:\\ExcelTest\\测试1.xlsx";        File file = new File(fileName);        if (file.exists()) {            file.delete();        }        //首先要使用Workbook类的工厂方法创建一个可写入的工作薄(Workbook)对象        Workbook wb = new XSSFWorkbook();        for (int i = 0; i < lastRowNum; i++) {            Sheet sheet = wb.createSheet("列表"+i);  //创建一个可写入的工作表            for (int r=0;r<lastRowNum;r++){                bt=0;//循环一次结束之后重新置为0                Row row = sheet.createRow(r);                for (int c=0;c<lists.get(r).size();c++){                    Cell cell = row.createCell(c);                    cell.setCellValue(lists.get(r).get(c));//                    if(bt>lastCellNum){//                        break;//                    }//                    else {//                        for (int value=0;value<lastCellNum-1;value++){////                           cell.setCellValue(lists.get(r).get(c));////                        }//                        bt++;//                    }                }            }        }        FileOutputStream fos = new FileOutputStream(file);        wb.write(fos);//从内存中写入文件中        fos.close();    }}