package poi;

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.IOException;

import java.io.InputStream;

import java.util.ArrayList;

import java.util.LinkedHashMap;

import java.util.List;

import java.util.Map;

import java.util.Map.Entry;

import org.apache.poi.hssf.usermodel.HSSFWorkbook;

import org.apache.poi.ss.usermodel.Cell;

import org.apache.poi.ss.usermodel.DateUtil;

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;

public class Testpoi {

    public static void main(String[] args) {

        Workbook wb =null;

        Sheet sheet = null;

        Row row = null;

        List<Map<String,String>> list = null;

        String cellData = null;

        String filePath = "D:\\test.xlsx";

        String columns[] = {"name","age","score"};

        wb = readExcel(filePath);

        if(wb != null){

            //用来存放表中数据

            list = new ArrayList<Map<String,String>>();

            //获取第一个sheet

            sheet = wb.getSheetAt(0);

            //获取最大行数

            int rownum = sheet.getPhysicalNumberOfRows();

            //获取第一行

            row = sheet.getRow(0);

            //获取最大列数

            int colnum = row.getPhysicalNumberOfCells();

            for (int i = 1; i<rownum; i++) {

                Map<String,String> map = new LinkedHashMap<String,String>();

                row = sheet.getRow(i);

                if(row !=null){

                    for (int j=0;j<colnum;j++){

                        cellData = (String) getCellFormatValue(row.getCell(j));

                        map.put(columns[j], cellData);

                    }

                }else{

                    break;

                }

                list.add(map);

            }

        }

        //遍历解析出来的list

        for (Map<String,String> map : list) {

            for (Entry<String,String> entry : map.entrySet()) {

                System.out.print(entry.getKey()+":"+entry.getValue()+",");

            }

            System.out.println();

        }

    }

    //读取excel

    public static Workbook readExcel(String filePath){

        Workbook wb = null;

        if(filePath==null){

            return null;

        }

        String extString = filePath.substring(filePath.lastIndexOf("."));

        InputStream is = null;

        try {

            is = new FileInputStream(filePath);

            if(".xls".equals(extString)){

                return wb = new HSSFWorkbook(is);

            }else if(".xlsx".equals(extString)){

                return wb = new XSSFWorkbook(is);

            }else{

                return wb = null;

            }

        } catch (FileNotFoundException e) {

            e.printStackTrace();

        } catch (IOException e) {

            e.printStackTrace();

        }

        return wb;

    }

    public static Object getCellFormatValue(Cell cell){

        Object cellValue = null;

        if(cell!=null){

            //判断cell类型

            switch(cell.getCellType()){

            case Cell.CELL_TYPE_NUMERIC:{

                cellValue = String.valueOf(cell.getNumericCellValue());

                break;

            }

            case Cell.CELL_TYPE_FORMULA:{

                //判断cell是否为日期格式

                if(DateUtil.isCellDateFormatted(cell)){

                    //转换为日期格式YYYY-mm-dd

                    cellValue = cell.getDateCellValue();

                }else{

                    //数字

                    cellValue = String.valueOf(cell.getNumericCellValue());

                }

                break;

            }

            case Cell.CELL_TYPE_STRING:{

                cellValue = cell.getRichStringCellValue().getString();

                break;

            }

            default:

                cellValue = "";

            }

        }else{

            cellValue = "";

        }

        return cellValue;

    }

}