使用POI导入Excel文件数据

package com.cn.test;


import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.text.DecimalFormat;
import java.util.ArrayList;


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.ss.usermodel.Workbook;


public class Excel {
private final String fileName;

public Excel(String fileName) {
super();
this.fileName = fileName;
}


public ArrayList<ArrayList<String>> getDataToArray(){
ArrayList<ArrayList<String>> result = new ArrayList<>();
try {
FileInputStream is = new FileInputStream(fileName);
return xlsToArray(is);
} catch (Exception e) {
e.printStackTrace();
}
return null;
}

public ArrayList<ArrayList<String>> xlsToArray(InputStream is){
Workbook workbook = null;
HSSFSheet sheet = null;
ArrayList<ArrayList<String>> result = new ArrayList<>();
try {
workbook = new HSSFWorkbook(is);
sheet = (HSSFSheet) workbook.getSheetAt(0);
for(int rowNumOfSheet = 0; rowNumOfSheet <= sheet.getLastRowNum();rowNumOfSheet++) {
HSSFRow row = sheet.getRow(rowNumOfSheet);
ArrayList<String> rows = new ArrayList<String>();

for(int cellNumOfSheet = 0; cellNumOfSheet < row.getLastCellNum();cellNumOfSheet++) {
HSSFCell cell = row.getCell(cellNumOfSheet);
String value = null;
if(cell != null) {
switch (cell.getCellType()) {
case 0:
value = new DecimalFormat("#.##").format(cell.getNumericCellValue()).toString();
break;
case 1:
value = cell.getStringCellValue();
if(value == null) {
value = "";
}
break;
case 4:
value = new Boolean(cell.getBooleanCellValue()).toString();
break;
}
}
if(value == null) {
value = "";
}
rows.add(value);
}
result.add(rows);
}
} catch (Exception e) {
e.printStackTrace();
}finally {
workbook.cloneSheet(0);
}
return result;
}

public static void main(String[] args) {
String path = "C:\\Users\\12\\Desktop\\1.xls";
File file = new File(path);
Excel excel = new Excel(file.toString());
ArrayList<ArrayList<String>> data = excel.getDataToArray();
System.out.println(data.size());
}
}