java使用POI处理EXCEL的核心类（二）

接上一篇写了使用poi导出excel，今天把读取excel的方法补上，核心类以下：

package cn.qazit.common.utils;

import java.io.ByteArrayOutputStream; import java.io.FileInputStream; import java.io.IOException; import java.io.InputStream; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.util.ArrayList; import java.util.Iterator; import java.util.List;

import org.apache.poi.hssf.usermodel.HSSFCell; import org.apache.poi.hssf.usermodel.HSSFCellStyle; 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.apache.poi.ss.usermodel.Sheet; import org.apache.poi.ss.usermodel.Workbook; import org.apache.poi.xssf.usermodel.XSSFWorkbook; import org.junit.internal.runners.statements.ExpectException;

import cn.qazit.app.core.charge.model.ZywsptGfxwjb; import cn.qazit.common.bean.ExportFiledsBean;

/**

• 导出的公共类

• @ClassName:ExportUtil.java

• @Title:ExportUtil.java

• @Description:

• @CopyRight:CopyRight(c)2016

• @Company:www.qazit.cn

• @author

• @date 2016年10月11日 下午7:14:05

• @version:v1.0 */ public class ExportUtil {

  /**

  • 导出的通用方法

  • @param sheet1

  • @param title

  • @param clazz

  • @param list

  • @return

  • @throws IOException

  • @throws ClassNotFoundException

  • @throws SecurityException

  • @throws NoSuchMethodException

  • @throws IllegalArgumentException

  • @throws Exception */ public static byte[] export(String sheet1, String title, Class<?> clazz,List<?> list) throws IOException, ClassNotFoundException, SecurityException, NoSuchMethodException, IllegalArgumentException, Exception{ ByteArrayOutputStream out = new ByteArrayOutputStream(); // 第一步，建立一个webbook，对应一个Excel文件
    HSSFWorkbook wb = new HSSFWorkbook(); // 第二步，在webbook中添加一个sheet,对应Excel文件中的sheet
    HSSFSheet sheet = wb.createSheet(sheet1); // 第三步，在sheet中添加表头第0行,注意老版本poi对Excel的行数列数有限制short

    HSSFRow row = sheet.createRow((int) 0); // 第四步，建立单元格，并设置值表头 设置表头居中
    HSSFCellStyle style = wb.createCellStyle(); style.setAlignment(HSSFCellStyle.ALIGN_CENTER); // 建立一个居中格式

    //设置表头
    List<ExportFiledsBean> excelHead = getExcelHead(clazz); Class _class = createClazz(clazz);

    HSSFCell cell = null; // excel头
    for (int i = 0; i < excelHead.size(); i++) {
    ExportFiledsBean exportFiledsBean = excelHead.get(i); cell = row.createCell(i);
    cell.setCellValue(exportFiledsBean.getName());
    cell.setCellStyle(style); }

    for (int i = 0;i<list.size();i++) { row = sheet.createRow((int) i + 1); Object obj = (Object) list.get(i); for(int j=0;j<excelHead.size();j++) { ExportFiledsBean exportFiledsBean = excelHead.get(j); String getFuncName = exportFiledsBean.getGetFuncName();

    Method addMethod = _class.getMethod(getFuncName);
     	Object result = addMethod.invoke(obj);
     	if(result==null)
     	{
     		row.createCell((int) j).setCellValue("");
     	}else{
     		row.createCell((int) j).setCellValue(result.toString());
     	}
     }

    } wb.write(out); // 第五步，写入实体数据 实际应用中这些数据从数据库获得 return out.toByteArray(); }

  private static List<ExportFiledsBean> getExcelHead(Class<?> clazz){ return AunotationUtil.getExportFileds(clazz); }

  private void insertCell(HSSFRow row,int i,Object object){
  if(object==null){
  row.createCell(i).setCellValue("");
  }else{
  row.createCell(i).setCellValue(object.toString());
  }

  }

  /**

  • 读取excel

  • @param fileName

  • @param clazz

  • @return

  • @throws ClassNotFoundException

  • @throws SecurityException

  • @throws NoSuchMethodException

  • @throws IllegalArgumentException

  • @throws Exception

  • @throws InvocationTargetException */ public static List<?> readExport(String fileName,Class<?> clazz) throws ClassNotFoundException, SecurityException, NoSuchMethodException, IllegalArgumentException, Exception, InvocationTargetException{ List<Object> list = new ArrayList<Object>(); List<ExportFiledsBean> excelHead = getExcelHead(clazz);

    Class _class = createClazz(clazz);

    boolean isE2007 = false; //判断是不是excel2007格式
    if(fileName.endsWith("xlsx"))
    isE2007 = true;
    try {
    InputStream input = new FileInputStream(fileName); //创建输入流 Workbook wb = creatWorkbook(isE2007,input);
    //根据文件格式(2003或者2007)来初始化
    Sheet sheet = wb.getSheetAt(0); //得到第一个表单
    Iterator<Row> rows = sheet.rowIterator(); //得到第一个表单的迭代器
    while (rows.hasNext()) {
    Row row = rows.next(); //得到行数据
    int rowNum = row.getRowNum(); if(rowNum>0) { Object obj = _class.newInstance(); Iterator<Cell> cells = row.cellIterator(); //得到第一行的迭代器
    while (cells.hasNext()) {
    Cell cell = cells.next();

    int cellColumnIndex = cell.getColumnIndex();
    
                 for(int i=0;i<excelHead.size();i++)
                 {   
                 	ExportFiledsBean exportFiledsBean = excelHead.get(i);
                 	int order = exportFiledsBean.getOrder();
                 	if(order==cellColumnIndex)
                 	{  
                 		String fitFuncName =  exportFiledsBean.getFitFuncName();
                         obj = addObjctList(cell,fitFuncName,obj,_class);
                 	}
                 }
             } 
             list.add(obj);
         }
     }

    } catch (IOException ex) {
    ex.printStackTrace();
    }
    return list; }

  private static Workbook creatWorkbook(boolean isE2007,InputStream input) throws IOException { Workbook wb = null; if(isE2007)
  wb = new XSSFWorkbook(input);
  else
  wb = new HSSFWorkbook(input);

  return wb;

  } /**

  • 使用反射机制建立对象
  • @param clazz
  • @return
  • @throws ClassNotFoundException */ private static Class createClazz(Class<?> clazz) throws ClassNotFoundException { String clazzName = clazz.getName(); Class _class = Class.forName(clazzName); return _class; }

  /**

  • 对象赋值
  • @param cell
  • @param addMethod
  • @param obj
  • @return
  • @throws IllegalArgumentException
  • @throws IllegalAccessException
  • @throws InvocationTargetException
  • @throws NoSuchMethodException
  • @throws SecurityException / private static Object addObjctList(Cell cell,String fitFuncName,Object obj,Class _class) throws IllegalArgumentException, IllegalAccessException, InvocationTargetException, SecurityException, NoSuchMethodException{ Method addMethod = null; switch (cell.getCellType()) { //根据cell中的类型来输出数据
    case HSSFCell.CELL_TYPE_NUMERIC:
    addMethod = _class.getMethod(fitFuncName,new Class[]{double.class}); addMethod.invoke(obj,cell.getNumericCellValue()); break;
    case HSSFCell.CELL_TYPE_STRING:
    addMethod = _class.getMethod(fitFuncName,new Class[]{String.class}); addMethod.invoke(obj,cell.getStringCellValue()); break;
    case HSSFCell.CELL_TYPE_BOOLEAN:
    addMethod = _class.getMethod(fitFuncName,new Class[]{boolean.class}); addMethod.invoke(obj,cell.getBooleanCellValue()); break;
    case HSSFCell.CELL_TYPE_FORMULA:
    addMethod = _class.getMethod(fitFuncName,new Class[]{String.class}); addMethod.invoke(obj,cell.getCellFormula()); break;
    default:
    addMethod = _class.getMethod(fitFuncName,new Class[]{String.class}); addMethod.invoke(obj,""); break;
    }
    return obj; } public static void main(String[] args) throws SecurityException, IllegalArgumentException, ClassNotFoundException, NoSuchMethodException, InvocationTargetException, Exception { List<ZywsptGfxwjb> list = (List<ZywsptGfxwjb>) readExport("D:/05download/例子/职业病基础知识.xls", ZywsptGfxwjb.class); System.out.println("结果对象**"); for(ZywsptGfxwjb z:list) { System.out.println(z.getMc()); } }

}