java解析Excel（xls、xlsx两种格式）

https://www.cnblogs.com/hhhshct/p/7255915.html

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一、需要导入的jar

　　1.commons-collections4-4.1.jar

　　2.poi-3.17-beta1.jar

　　3.poi-ooxml-3.17-beta1.jar

　　4.poi-ooxml-schemas-3.17-beta1.jar

　　5.xmlbeans-2.6.0.jar

maven

  <dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi-ooxml</artifactId>
    <version>3.17</version>
</dependency>

二、主要API

　　1.import org.apache.poi.ss.usermodel.Workbook,对应Excel文档；

　　2.import org.apache.poi.hssf.usermodel.HSSFWorkbook，对应xls格式的Excel文档；

　　3.import org.apache.poi.xssf.usermodel.XSSFWorkbook，对应xlsx格式的Excel文档；

　　4.import org.apache.poi.ss.usermodel.Sheet，对应Excel文档中的一个sheet；

　　5.import org.apache.poi.ss.usermodel.Row，对应一个sheet中的一行；

　　6.import org.apache.poi.ss.usermodel.Cell，对应一个单元格。

三、代码如下

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;
    }

}

四、运行结果

　　代码运行前保证在D盘下有一个test.xlsx文档，不然报文件找不到异常；Excel文档中的表头要和代码中的String columns[] = {"name","age","score"}对应起来。

例2

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;

import org.apache.poi.xssf.usermodel.XSSFRow;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

public class TestExcel {

    public static void main(String[] args) throws IOException{
          // 创建工作薄 xlsx
        XSSFWorkbook  xssWorkbook = new XSSFWorkbook();
          // 创建工作表
        XSSFSheet  sheet = xssWorkbook.createSheet("sheet1");

          for (int row = 0; row < 10; row++)
          {
              XSSFRow  rows = sheet.createRow(row);
             for (int col = 0; col < 10; col++)
             {
                // 向工作表中添加数据
                rows.createCell(col).setCellValue("data" + row + col);
             }
          }
//
          File xlsFile = new File("poi.xlsx");
          FileOutputStream xlsStream = new FileOutputStream(xlsFile);
          xssWorkbook.write(xlsStream);
    }
}