FileUpload组件

package com.itheima.servlet;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.io.UnsupportedEncodingException;

import java.text.DateFormat;

import java.text.SimpleDateFormat;

import java.util.ArrayList;

import java.util.Date;

import java.util.List;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.apache.commons.fileupload.FileItem;

import org.apache.commons.fileupload.FileUploadBase;

import org.apache.commons.fileupload.FileUploadException;

import org.apache.commons.fileupload.disk.DiskFileItemFactory;

import org.apache.commons.fileupload.servlet.ServletFileUpload;

import org.apache.commons.io.FilenameUtils;

import com.itheima.util.IdGenertor;

public class UploadServlet3 extends HttpServlet {

public void doGet(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

request.setCharacterEncoding("UTF-8");

response.setContentType("text/html;charset=UTF-8");

//检测form是否是multipart/form-data类型的

boolean isMultipart = ServletFileUpload.isMultipartContent(request);

if(!isMultipart){

throw new RuntimeException("The form's enctype attribute value must be multipart/form-data");

}

//解析请求内容

DiskFileItemFactory factory = new DiskFileItemFactory();//产生FileItem的工厂

factory.setRepository(new File("d:/"));//指定临时文件的存放目录

ServletFileUpload sfu = new ServletFileUpload(factory);

//	sfu.setFileSizeMax(3*1024*1024);//单个文件大小限制

//	sfu.setSizeMax(5*1024*1024);//总文件大小

List<FileItem> items = new ArrayList<FileItem>();

try {

items = sfu.parseRequest(request);

}catch(FileUploadBase.FileSizeLimitExceededException e) {

response.getWriter().write("单个文件不能超过3M");

}

catch(FileUploadBase.SizeLimitExceededException e) {

response.getWriter().write("总文件不能超过5M");

}catch (FileUploadException e) {

e.printStackTrace();

throw new RuntimeException("解析请求失败");

}

//遍历：

for(FileItem item:items){

//处理普通字段

if(item.isFormField()){

processFormField(item);

}else{

//处理上传字段

processUploadField(item);

}

}

}

protected void processUploadField(FileItem item) {

try {

//	InputStream in = item.getInputStream();

//找一个存放文件的位置；存放的文件名

String fileName = item.getName();//上传的文件的文件名 C:\Users\wzhting\Desktop\a.txt a.txt(浏览器不同)

if(fileName!=null&&!fileName.equals("")){

//限定上传文件的类型

if(!item.getContentType().startsWith("image")){

return;

}

fileName = FilenameUtils.getName(fileName);

fileName = IdGenertor.genGUID()+"_"+fileName;

//存放路径

String realPath = getServletContext().getRealPath("/WEB-INF/files");

//生成一个子目录

String childDirectory = genChildDirectory(realPath,fileName);

File storeDirectory = new File(realPath+File.separator+childDirectory);

if(!storeDirectory.exists()){

storeDirectory.mkdirs();

}

//	OutputStream out = new FileOutputStream(new File(storeDirectory, fileName));

//

//	int len = -1;

//	byte b[] = new byte[1024];

//	while((len=in.read(b))!=-1){

//	out.write(b, 0, len);

//	}

//	in.close();

//	out.close();

//

//	item.delete();//清除临时文件

item.write(new File(storeDirectory, fileName));

}

} catch (Exception e) {

e.printStackTrace();

}

}

private String genChildDirectory(String realPath, String fileName) {

int hashCode = fileName.hashCode();

int dir1 = hashCode&0xf;

int dir2 = (hashCode&0xf0)>>4;

String str = dir1+File.separator+dir2;

File file = new File(realPath,str);

if(!file.exists()){

file.mkdirs();

}

return str;

}

//按照日期生成子目录

private String genChildDirectory(String realPath) {

Date now = new Date();

DateFormat df = new SimpleDateFormat("yyyy-MM-dd");

String str = df.format(now);

File file = new File(realPath,str);

if(!file.exists()){

file.mkdirs();

}

return str;

}

protected void processFormField(FileItem item) {

//打印到控制台

String fieldName = item.getFieldName();

String fieldValue = "";

try {

fieldValue = item.getString("UTF-8");

} catch (UnsupportedEncodingException e) {

e.printStackTrace();

}

System.out.println(fieldName+"="+fieldValue);

}

public void doPost(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

doGet(request, response);

}

}