文件的导入

jsp：

   <s:form action="import.action" method="post" enctype="multipart/form-data" theme="simple">
   <table border="1">
   <tr>
   <td>文件上传</td>
   </tr>
   <tr>
   <td>
   <s:file name="uploadFile" label="文件位置" size="80"/>
   </td>
   </tr>
   <tr><td>
   <s:submit value="submit"></s:submit>
   <s:reset value="reset"></s:reset>
   </td></tr>
   </table>
   </s:form>

action：上传文件的文件如果为uploadFile,那么文件名一定要为uploadFileFileName,也就是在文件后加入FileName,不然不能识别

package excl;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.apache.commons.io.FileUtils;
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.struts2.ServletActionContext;
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.Transaction;

import test.BaseAction;
import test.User;

public class Import extends BaseAction{
	private static final String SUCCESS = "success";
	private File uploadFile=null;
	private String uploadFileFileName=null;
	
	
	public String loadRoleFile() {
	String directory="/upload/role";
	String targetDirectory=
		ServletActionContext.getServletContext().getRealPath(directory);
	String file=targetDirectory+"\\"+uploadFileFileName;
	//生成上传的文件对象
	File target = new File(file);
	//如果文件已经存在，则删除源文件
	if(target.exists()){
		target.delete();
	}
	System.out.println(uploadFile);
	System.out.println(uploadFileFileName);
	//复制file对象，实现上传
	try {
		FileUtils.copyFile(uploadFile,target);
	} catch (IOException e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
	} 
	
	List roleList = new ArrayList();
	
	try {
		
	FileInputStream fi = new FileInputStream(target);
	Workbook wb = new HSSFWorkbook(fi);
	Sheet sheet = wb.getSheetAt(0);
	int rowNum = sheet.getLastRowNum()+1;
	for(int i=1;i<rowNum;i++){
		User user = new User();
		Row row = sheet.getRow(i);
		int cellNum = row.getLastCellNum();
		for(int j=0;j<cellNum;j++){
			Cell cell = row.getCell(j);
			String cellValue=null;
			switch(cell.getCellType()){
			//判断 excel单元格内容的格式，并对其进行转换，以便插入数据库
			case 0:cellValue=String .valueOf((int)cell.getNumericCellValue());break;
			case 1 : cellValue = cell.getStringCellValue(); break;  
            case 2 : cellValue = String.valueOf(cell.getDateCellValue()); break;  
            case 3 : cellValue = ""; break;  
            case 4 : cellValue = String.valueOf(cell.getBooleanCellValue()); break;  
            case 5 : cellValue = String.valueOf(cell.getErrorCellValue()); break;  
			}
			 switch(j){//通过列数来判断对应插如的字段  
             case 0 : user.setId(Integer.parseInt(cellValue));break;  
             case 1 : user.setPassword(cellValue);break;  
             case 2 : user.setUsername(cellValue);break;  
         }
		}
		roleList.add(user);
	}
	} catch (IOException e) {
		e.printStackTrace();
	}
	Session session = this.getHibernateTemplate().getSessionFactory().openSession();
	Transaction tx = null;
	try {
		tx=null;
		tx=session.beginTransaction();
		if(roleList.size()>0){
			int roleNum=roleList.size();
			for(int i=0;i<roleNum;i++){
				session.save(roleList.get(i));
			}
			tx.commit();
		}
	} catch (HibernateException e) {
		tx.rollback();
		e.printStackTrace();
	}finally{
		session.close();
	}
	return SUCCESS;
	}

	public String getUploadFileFileName() {
		return uploadFileFileName;
	}


	public void setUploadFileFileName(String uploadFileFileName) {
		this.uploadFileFileName = uploadFileFileName;
	}


	
	public File getUploadFile() {
		return uploadFile;
	}
	public void setUploadFile(File uploadFile) {
		this.uploadFile = uploadFile;
	}
	
}

1：导入导出jar包的区别‘
2： private File uploadFile=null;
private String uploadFileFileName=null;

为什么不加“=null”值就传不进来

3：String directory="/upload/role";
String targetDirectory=
ServletActionContext.getServletContext().getRealPath(directory);

--》targetDirectory = D:\lxq\zhuanyi\jar+js\apache-tomcat-5.5.23\webapps\TinyBee\upload\role