【poi】用POI新建一个xlsx文件【或者说将数据存入到xlsx中】/【将数据从xlsx中获取到项目中】

package com.it.poiTest;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

public class GetWorkBook {

public static <E> void main(String[] args) {
//1。前三步获取xlsx文件对象
File file = new File("createWorkBook.xlsx");
try {
//2.
FileInputStream in = new FileInputStream(file);
//3。
XSSFWorkbook workbook = new XSSFWorkbook(in);
//4.获取工作簿对象
Sheet sheet = workbook.getSheetAt(0);
//Sheet sheet1 = workbook.getSheet("first sheet");   效果一样
//5.迭代取出数据
Iterator<Row> rowItera = sheet.iterator();
List<Object[]> list =(List<Object[]>) new ArrayList<E>();
Row row;
while(rowItera.hasNext()){
row = rowItera.next();
Iterator<Cell> cellItera = row.cellIterator();
Cell cell;
while(cellItera.hasNext()){
cell = cellItera.next();
//6.打印
System.out.print(cell.getStringCellValue() + "   ");
}
System.out.println("\n");
}

} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}

}