POI的入门学习（二）遍历工作簿的行和列输出单元格内容

        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi</artifactId>
            <version>3.15</version>
        </dependency>

package cn.jp.poi.demo.test;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.poifs.filesystem.POIFSFileSystem;
import java.io.FileInputStream;
import java.io.InputStream;
/**
 * @author JP
 * @title: Demo4
 * @projectName demoPoi
 * @description: 遍历excel输出内容
 * @date 2019/5/13 0013
 */
public class Demo4 {
    public static void main(String[] args) throws Exception {
        //文件输入流导入excel文件
        InputStream inputStream=new FileInputStream("c:\\demo3.xls");
        POIFSFileSystem fileSystem=new POIFSFileSystem(inputStream);
        HSSFWorkbook workbook=new HSSFWorkbook(fileSystem);
        HSSFSheet sheet=workbook.getSheetAt(0); //获取第一个sheet页
        if (sheet==null){
            return;
        }
        //遍历行Row
        System.out.println(sheet.getLastRowNum());
        for(int i=0;i<=sheet.getLastRowNum();i++){
            HSSFRow row=sheet.getRow(i); //获取单行
            if (row==null){
                return;
            }
            //遍历列
            for(int j=0;j<=row.getLastCellNum();j++){
                HSSFCell cell=row.getCell(j); //获取单列
                if(cell ==null){
                    continue;
                }
                System.out.print(" "+getValue(cell));
            }
            System.out.println();
        }
    }
    private static String getValue(HSSFCell cell){
        if(cell.getCellType() ==HSSFCell.CELL_TYPE_BOOLEAN){ //若为boolean类型
            return String.valueOf(cell.getBooleanCellValue());
        }else if (cell.getCellType() ==HSSFCell.CELL_TYPE_NUMERIC){ //若为数字类型
            return String.valueOf(cell.getNumericCellValue());
        }else {
            return String.valueOf(cell.getStringCellValue()); //其他类型统一返回字符串
        }
    }
}