JavaWeb——文件上傳
阿新 • • 發佈：2018-02-21
pat new org 獲得 lean blog 路徑 protect b16
HTML
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<form action="/WEB16/upload" method="post" enctype="multipart/form-data">
<input type="text" name="text">
<input type="file" name="filename">
<input type="submit">
</form>
</body>
</html>
文件上傳（普通版）
package cn.x5456.uploadDemo;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.List;
@WebServlet(name = "FileuploadServlet")
public class FileuploadServlet extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//1.創建磁盤文件項工廠
DiskFileItemFactory factory = new DiskFileItemFactory();
//2.實例化文件上傳核心類
ServletFileUpload upload = new ServletFileUpload(factory);
//設置上傳文件的名稱的編碼
upload.setHeaderEncoding("UTF-8");
//3.解析request---獲得文件項集合
List<FileItem> list = null;
try {
list = upload.parseRequest(request);
} catch (FileUploadException e) {
e.printStackTrace();
}
//4.遍歷集合
for(FileItem item : list){
// 判斷是否為表單項
boolean formField = item.isFormField();
// 表單項
if(formField){
String fieldName = item.getFieldName();
String fieldValue = item.getString();
System.out.println(fieldName+"："+fieldValue);
}// 文件上傳項
else{
// 獲取文件名
String fileName = item.getName();
// 獲取文件輸入流
InputStream in = item.getInputStream();
// 獲取真路徑
String path = super.getServletContext().getRealPath("WEB-INF/upload");
// 設置輸出路徑
OutputStream out = new FileOutputStream(path+"/"+fileName);
int len = 0;
byte[] b = new byte[1024];
while ((len=in.read(b))!=-1){
out.write(b,0,len);
}
in.close();
out.close();
}
}
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
}
}文件上傳（緩沖區版）
package com.itheima;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
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.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.apache.commons.io.IOUtils;
public class FileuploadServlet2 extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
try {
//1、創建磁盤文件項工廠
//作用：設置緩存文件的大小 設置臨時文件存儲的位置
String path_temp = this.getServletContext().getRealPath("temp");
//DiskFileItemFactory factory = new DiskFileItemFactory(1024*1024, new File(path_temp));
DiskFileItemFactory factory = new DiskFileItemFactory();
factory.setSizeThreshold(1024*1024);
factory.setRepository(new File(path_temp));
//2、創建文件上傳的核心類
ServletFileUpload upload = new ServletFileUpload(factory);
//設置上傳文件的名稱的編碼
upload.setHeaderEncoding("UTF-8");
//ServletFileUpload的API
boolean multipartContent = upload.isMultipartContent(request);//判斷表單是否是文件上傳的表單
if(multipartContent){
//是文件上傳的表單
//***解析request獲得文件項集合
List<FileItem> parseRequest = upload.parseRequest(request);
if(parseRequest!=null){
for(FileItem item : parseRequest){
//判斷是不是一個普通表單項
boolean formField = item.isFormField();
if(formField){
//username=zhangsan
String fieldName = item.getFieldName();
String fieldValue = item.getString("UTF-8");//對普通表單項的內容進行編碼
System.out.println(fieldName+"----"+fieldValue);
//當表單是enctype="multipart/form-data"時 request.getParameter相關的方法
//String parameter = request.getParameter("username");
}else{
//文件上傳項
//文件的名
String fileName = item.getName();
//獲得上傳文件的內容
InputStream in = item.getInputStream();
String path_store = this.getServletContext().getRealPath("upload");
OutputStream out = new FileOutputStream(path_store+"/"+fileName);
IOUtils.copy(in, out);
in.close();
out.close();
//刪除臨時文件
item.delete();
}
}
}
}else{
//不是文件上傳表單
//使用原始的表單數據的獲得方式 request.getParameter();
}
} catch (FileUploadException e) {
e.printStackTrace();
}
}
public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request, response);
}
}
JavaWeb——文件上傳