前段需要写个上传文件的功能

前段需要写个上传文件的功能，现在就把他贴上来。

 

package com.xiaobus.util;

import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Random;

import javax.servlet.http.HttpServletRequest;
import org.apache.struts.upload.FormFile;



/** *//**
 * <pre>
 * ------------------------------
 * Name: xiaobus System
 * Author: Shawn
 * CopyRight: cama company
 * WebSite: http://blog.youkuaiyun.com/xdy3008
 * Email: xiao.dongyi@gmail.com
 * Date: Sep 3, 2007
 * ------------------------------
 * </pre>
 */

public class FileUpLoadUtil ...{
    
    public final static String imageFlag_Old_New = "new";

    // 上传文件,返回文件名字
    public static String uploadFile(FormFile file, HttpServletRequest request) ...{
        String uploadFileAllowedExt = PropertiesCache.getInstance()
                .getUploadFileAllowedExt();
        long uploadFileMaxSize = PropertiesCache.getInstance()
                .getUploadFileMaxSize();
        String uploadFileDirectory = PropertiesCache.getInstance()
                .getUploadFileDirectory();

        String fileName = null;
        String filePath = null;
        int len = file.getFileName().length();
        int tempIndex = file.getFileName().lastIndexOf(".");
        String ext = file.getFileName().substring(tempIndex + 1, len);

        try ...{
            if (file.getFileSize() < uploadFileMaxSize
                    && uploadFileAllowedExt.indexOf(ext) != -1) ...{
                InputStream stream = file.getInputStream();
                String contextPath = request.getRealPath("/");
                contextPath = contextPath + uploadFileDirectory;
                fileName = createFileName(ext);
                if (fileName == null) ...{
                    return null;
                }
                filePath = createFilePath(uploadFileDirectory,contextPath);
                OutputStream bos = new FileOutputStream(filePath + fileName);
                int bytesRead = 0;
                byte[] buffer = new byte[8192];
                while ((bytesRead = stream.read(buffer, 0, 8192)) != -1) ...{
                    bos.write(buffer, 0, bytesRead);
                }
                bos.close();
                stream.close();
                int index = filePath.indexOf(uploadFileDirectory);
                int length = filePath.length();
                return filePath.substring(index + uploadFileDirectory.length(),
                        length)
                        + fileName;
            } else ...{
                return null;
            }
        } catch (Exception e) ...{
            e.printStackTrace();
            System.out.println("Error happan when uploadFile.");
            return null;

        }
    }

    public static String createFilePath(String uploadFileDirectory,String contextPath) ...{
        Date today = new Date();
        String year, month, day;
        year = new SimpleDateFormat("yyyy").format(today);
        month = new SimpleDateFormat("MM").format(today);
        day = new SimpleDateFormat("dd").format(today);
        
        //如果没有上传文件的文件夹，就创建一个
        if (!(new File(contextPath).exists())) ...{
            new File(contextPath).mkdir();
        }
        
        
        String dic = contextPath + "/" + year;
        if (!(new File(dic).exists())) ...{
            new File(dic).mkdir();
        }
        dic = dic + "/" + month;
        if (!(new File(dic).exists())) ...{
            new File(dic).mkdir();
        }
        dic = dic + "/" + day;
        if (!(new File(dic).exists())) ...{
            new File(dic).mkdir();
        }
        return dic + "/";
    }

    public static String createFileName(String ext) ...{
        if (ext.equals("")) ...{
            return null;
        }
        Random r = new Random();
        return "" + System.currentTimeMillis() + r.nextInt(9999) + "." + ext;
    }

    public static String createFileNameNew(String ext) ...{
        if (ext.equals("")) ...{
            return null;
        }
        return "file" + System.currentTimeMillis() + imageFlag_Old_New + "." + ext;
    }
    

    
    public static void main(String[] args) ...{
        String a = "c:/";
        String dic = a + "AAAAAAAAAAAA";
        if (!(new File(dic).exists())) ...{
            new File(dic).mkdir();
            System.out.println("no , but now create one.");
        }
        else...{
            System.out.println("exist ！");
        }
    }
}