一 代码

package WorkbookTest;import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import java.io.*;/**
* Copyright (C), 2020-2020, XXX有限公司
* FileName: Workbook
* Author:   cakin
* Date:     2020/1/18
* Description: 获取对应Excel文件的Workbook对象
*/
public class WorkbookTest {public static void main( String[] args ) {String file = "F:\\Javatest\\tempTest\\test.xlsx";File fileTest = new File(file);Workbook workbook = getWorkbook(fileTest);System.out.println("workbook:"+workbook);}public static Workbook getWorkbook( File file ) {Workbook wb = null;try {if (file.exists() && file.isFile()) {// 文件名String fileName = file.getName();// 文件扩展名String extension = fileName.lastIndexOf(".") == -1 ? "" : fileName.substring(fileName.lastIndexOf(".") + 1);// 文件输入流FileInputStream fileInputStream = new FileInputStream(file);try {if ("xls".equals(extension)) { //Excel 2003// 参考   https://www.cnblogs.com/fqfanqi/p/6172223.html// 得到Excel工作簿对象wb = new HSSFWorkbook(fileInputStream);} else if ("xlsx".equals(extension)) { //Excel 2007wb = new XSSFWorkbook(fileInputStream);} else {throw new IOException("not support the file type");}} catch (Exception e) {e.printStackTrace();} finally {try {// 关闭资源System.out.println("关闭资源");fileInputStream.close();} catch (Exception e) {e.printStackTrace();}}}return wb;} catch (Exception e) {e.printStackTrace();}return null;}
}

二 测试

1 文件名存在时打印

关闭资源
workbook:Name: /xl/workbook.xml - Content Type: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet.main+xml

2 文件不存在时打印

workbook:null

3 后缀名非法时的打印

java.io.IOException: not support the file type
关闭资源at WorkbookTest.WorkbookTest.getWorkbook(WorkbookTest.java:41)at WorkbookTest.WorkbookTest.main(WorkbookTest.java:19)
workbook:null