POI依賴的jar包：
<org.apache.poi.version>3.10-FINAL</org.apache.poi.version>

        <!-- POI的jar包-->
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi</artifactId>
            <version>${org.apache.poi.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi-ooxml-schemas</artifactId>
            <version>${org.apache.poi.version}</version>
        </dependency>

        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi-ooxml</artifactId>
            <version>${org.apache.poi.version}</version>
        </dependency>
 

java POI讀取excel模版並填寫資料程式碼:

public class ExportExcelDemo {
    private HSSFWorkbook workbook = null;
    /**
     * 顯示的匯出表的標題
     */
    private String title;
    /**
     * 匯出表的列名
     */
    private String[] rowName;

    private List<Object[]> dataList = new ArrayList<>();

    /**
     * 構造方法，傳入要匯出的資料
     *
     * @param title
     * @param rowName
     * @param dataList
     */
    public ExportExcelDemo(String title, String[] rowName, List<Object[]> dataList) {
        this.dataList = dataList;
        this.rowName = rowName;
        this.title = title;
    }


    /**
     * 判斷檔案的sheet是否存在
     * @param filePath      檔案路徑
     * @param sheetName     表格索引名
     * @return
     */
    public boolean sheetExist(String filePath,String sheetName){
        boolean flag = false;
        File file = new File(filePath);
        if(file.exists()) {    //檔案存在
            //建立workbook
            try {
                workbook = new HSSFWorkbook(new FileInputStream(file));
                //新增Worksheet（不新增sheet時生成的xls檔案開啟時會報錯)
                HSSFSheet sheet = workbook.getSheet(sheetName);
                if(sheet!=null)
                     flag = true;
            } catch (Exception e) {
                e.printStackTrace();
            }
        }else{  //檔案不存在
            flag =false;
        }
        return flag;
    }

    /**
     *
     *(2003 xls字尾 匯出)
     * @param TODO
     * @return void 返回型別
     * @author xsw
     * @2016-12-7上午10:44:00
     */
    public static void createXLS(String importFilePath,String exportFilePath) throws IOException{
        try {
            //excel模板路徑
            File fi=new File(importFilePath);
            POIFSFileSystem fs = new POIFSFileSystem(new FileInputStream(fi));
            //讀取excel模板
            HSSFWorkbook wb = new HSSFWorkbook(fs);
            //讀取了模板內所有sheet內容
            HSSFSheet sheet = wb.getSheetAt(0);

            //如果這行沒有了，整個公式都不會有自動計算的效果的
            sheet.setForceFormulaRecalculation(true);


            //在相應的單元格進行賦值
            HSSFCell cell = sheet.getRow(11).getCell(6);//第11行 第6列
            cell.setCellValue(1);
            HSSFCell cell2 = sheet.getRow(11).getCell(7);
            cell2.setCellValue(2);
            sheet.getRow(12).getCell(6).setCellValue(12);
            sheet.getRow(12).getCell(7).setCellValue(12);
            //修改模板內容匯出新模板
            FileOutputStream out = new FileOutputStream(exportFilePath);
            wb.write(out);
            out.close();
        }catch (Exception e) {
            System.out.println("檔案讀取錯誤!");
        }

    }

    /**
     *
     *(2007 xlsx字尾 匯出)
     * @param
     * @return void 返回型別
     * @author xsw
     * @2016-12-7上午10:44:30
     */
    public static void createXLSX(String importFilePath,String exportFilePath) throws IOException{
        //excel模板路徑
        File fi=new File(importFilePath);
        InputStream in = new FileInputStream(fi);
        //讀取excel模板
        XSSFWorkbook wb = new XSSFWorkbook(in);
        //讀取了模板內所有sheet內容
        XSSFSheet sheet = wb.getSheetAt(0);

        //如果這行沒有了，整個公式都不會有自動計算的效果的
        sheet.setForceFormulaRecalculation(true);


        //在相應的單元格進行賦值
        XSSFCell cell = sheet.getRow(11).getCell(6);//第12行 第7列
        cell.setCellValue(1);
        XSSFCell cell2 = sheet.getRow(11).getCell(7);
        cell2.setCellValue(2);
        sheet.getRow(12).getCell(6).setCellValue(3);
        sheet.getRow(12).getCell(7).setCellValue(4);
        //修改模板內容匯出新模板
        FileOutputStream out = new FileOutputStream(exportFilePath);
        wb.write(out);
        out.close();
    }

    /**
     * @param @param  file
     * @param @return
     * @param @throws IOException
     * @return List<String> (excel每行拼接成List中的String)
     * @throws
     * @Title: readExcel
     * @Description: TODO(對外提供讀取excel 的方法)
     */
    public static synchronized void readExcel(String importFilePath,String exportFilePath) throws IOException {
        File file=new File(importFilePath);
        String fileName = file.getName();
        //List<String> list = new ArrayList<String>();
        //根據其名稱獲取字尾
        String extension = fileName.lastIndexOf(".") == -1 ? "" : fileName
                .substring(fileName.lastIndexOf(".") + 1);
        if ("xls".equals(extension)) {
            read2003Excel(new FileInputStream(file),exportFilePath);
        } else if ("xlsx".equals(extension) || "xlsm".equals(extension)) {
            read2007Excel(new FileInputStream(file),exportFilePath);
        } else if ("tmp".equals(extension)) {
            read2007Excel(new FileInputStream(file),exportFilePath);
        } else {
            throw new IOException("不支援的檔案型別");
        }
    }

    public static void main(String[] args) throws IOException{
        //excle 2007
        String importFilePath= "/Users/dataDemo.xlsx";
        String exportFilePath= "/Users/test2.xlsx";
        //createXLSX(importFilePath,exportFilePath);
        readExcel(importFilePath,exportFilePath);
    }
}