java使用poi包将数据写入Excel表格

1、Excel相关操作代码

 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.lang.reflect.Field;
 import java.lang.reflect.Method;
 import java.util.ArrayList;
 import java.util.List;

 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.Cell;
 import org.apache.poi.ss.usermodel.Row;
 import org.springframework.stereotype.Component;

 /**
  * @Description:
  * @author  * @date 创建时间：2016年12月8日下午2:38:47
  * @version 1.0
  */
 @Component
 public class ExcelManage {
     private HSSFWorkbook workbook = null;  

     /**
      * 判断文件是否存在
      * @param filePath  文件路径
      * @return
      */
     public boolean fileExist(String filePath){
          boolean flag = false;
          File file = new File(filePath);
          flag = file.exists();
          return flag;
     }  

     /**
      * 判断文件的sheet是否存在
      * @param filePath   文件路径
      * @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()){    //文件存在
             //创建workbook
              try {
                 workbook = new HSSFWorkbook(new FileInputStream(file));
                 //添加Worksheet（不添加sheet时生成的xls文件打开时会报错)
                 HSSFSheet sheet = workbook.getSheet(sheetName);
                 if(sheet!=null)
                     flag = true;
             } catch (Exception e) {
                 e.printStackTrace();
             }
          }else{    //文件不存在
              flag = false;
          }
          return flag;
     }
     /**
      * 创建新Sheet并写入第一行数据
      * @param filePath  excel的路径
      * @param sheetName 要创建的表格索引
      * @param titleRow excel的第一行即表格头
      * @throws IOException
      * @throws FileNotFoundException
      */
     public void createSheet(String filePath,String sheetName,String titleRow[]) throws FileNotFoundException, IOException{
         FileOutputStream out = null;
         File excel = new File(filePath);  // 读取文件
         FileInputStream in = new FileInputStream(excel); // 转换为流
         workbook = new HSSFWorkbook(in); // 加载excel的 工作目录       

         workbook.createSheet(sheetName); // 添加一个新的sheet
         //添加表头
         Row row = workbook.getSheet(sheetName).createRow(0);    //创建第一行
         try {
             for(int i = 0;i < titleRow.length;i++){
                 Cell cell = row.createCell(i);
                 cell.setCellValue(titleRow[i]);
             }
             out = new FileOutputStream(filePath);
             workbook.write(out);
        }catch (Exception e) {
            e.printStackTrace();
        }finally {
            try {
                out.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
     }
 99     /**
      * 创建新excel.
      * @param filePath  excel的路径
      * @param sheetName 要创建的表格索引
      * @param titleRow excel的第一行即表格头
      */
     public void createExcel(String filePath,String sheetName,String titleRow[]){
         //创建workbook
         workbook = new HSSFWorkbook();
         //添加Worksheet（不添加sheet时生成的xls文件打开时会报错)
         workbook.createSheet(sheetName);
         //新建文件
         FileOutputStream out = null;
         try {
             //添加表头
             Row row = workbook.getSheet(sheetName).createRow(0);    //创建第一行
             for(int i = 0;i < titleRow.length;i++){
                 Cell cell = row.createCell(i);
                 cell.setCellValue(titleRow[i]);
             }
             out = new FileOutputStream(filePath);
             workbook.write(out);
         } catch (Exception e) {
             e.printStackTrace();
         } finally {
             try {
                 out.close();
             } catch (IOException e) {
                 e.printStackTrace();
             }
         }
     }
     /**
      * 删除文件.
      * @param filePath  文件路径
      */
     public boolean deleteExcel(String filePath){
         boolean flag = false;
         File file = new File(filePath);
         // 判断目录或文件是否存在
         if (!file.exists()) {
             return flag;
         } else {
             // 判断是否为文件
             if (file.isFile()) {  // 为文件时调用删除文件方法
                 file.delete();
                 flag = true;
             }
         }
         return flag;
     }
     /**
      * 往excel中写入.
      * @param filePath    文件路径
      * @param sheetName  表格索引
      * @param object
      */
     public void writeToExcel(String filePath,String sheetName, Object object,String titleRow[]){
         //创建workbook
         File file = new File(filePath);
         try {
             workbook = new HSSFWorkbook(new FileInputStream(file));
         } catch (FileNotFoundException e) {
             e.printStackTrace();
         } catch (IOException e) {
             e.printStackTrace();
         }
         FileOutputStream out = null;
         HSSFSheet sheet = workbook.getSheet(sheetName);
         // 获取表格的总行数
         int rowCount = sheet.getLastRowNum() + 1; // 需要加一
         try {
             Row row = sheet.createRow(rowCount);     //最新要添加的一行
             //通过反射获得object的字段,对应表头插入
             // 获取该对象的class对象
             Class<? extends Object> class_ = object.getClass();              

             for(int i = 0;i < titleRow.length;i++){
                 String title = titleRow[i];
                 String UTitle = Character.toUpperCase(title.charAt(0))+ title.substring(1, title.length()); // 使其首字母大写;
                 String methodName  = "get"+UTitle;
                 Method method = class_.getDeclaredMethod(methodName); // 设置要执行的方法
                 String data = method.invoke(object).toString(); // 执行该get方法,即要插入的数据
                 Cell cell = row.createCell(i);
                 cell.setCellValue(data);
             }
             out = new FileOutputStream(filePath);
             workbook.write(out);
         } catch (Exception e) {
             e.printStackTrace();
         } finally {
             try {
                 out.close();
             } catch (IOException e) {
                 e.printStackTrace();
             }
         }
     }
 }

2、main方法调用方式

 public static void main(String[] args) {
     String filePath = "result/数据汇总.xls";
     String sheetName = "测试";
     //Excel文件易车sheet页的第一行
     String title[] = {"日期", "城市","新发布车源数"};
     //Excel文件易车每一列对应的数据
     String titleDate[] = {"date", "city","newPublish"};

     ExcelManage em = new ExcelManage();
     //判断该名称的文件是否存在
     boolean fileFlag = em.fileExist(filePath);
     if(!fileFlag){
        em.createExcel(filePath,sheetName,title);
     }
     //判断该名称的Sheet是否存在
     boolean sheetFlag = em.sheetExist(filePath,sheetName);
     //如果该名称的Sheet不存在，则新建一个新的Sheet
     if(!sheetFlag){
        try {
            em.createSheet(filePath,sheetName,title);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
     }
     YiCheData user = new YiCheData();
     user.setDate("206-12-21");
     user.setCity("北京");
     user.setNewPublish("5");
     //写入到excel
     em.writeToExcel(filePath,sheetName,user,titleDate);
 }

3、用于测试的bean类

 public class YiCheData {
     private String date;
     private String city;
     private String newPublish;  

     public String getDate() {
         return date;
     }
     public void setDate(String date) {
         this.date = date;
     }
     public String getCity() {
     　　return city;
     }
     public void setCity(String city) {
    　　 this.city = city;
     }
     public String getNewPublish() {
     　　eturn newPublish;
     }
     public void setNewPublish(String newPublish) {
     　　this.newPublish = newPublish;
     }
 }        

以上代码请参考：http://www.open-open.com/lib/view/open1433238476150.html