使用ServletFileUpload实现上传

使用ServletFileUpload实现上传

转载自/article/9156547.html

1.首先我们应该为上传的文件建一个存放的位置，一般位置分为临时和真是文件夹，那我们就需要获取这俩个文件夹的绝对路径，在servlet中我们可以这样做

[java]
view plaincopyprint?

ServletContext application = this.getServletContext();

String tempDirectory = application.getRealPath(Constant.TEMP_DIRECTORY) +
"/";
String realDirectory = application.getRealPath(Constant.REAL_DIRECTORY) +
"/";

ServletContext application = this.getServletContext();
String tempDirectory = application.getRealPath(Constant.TEMP_DIRECTORY) + "/";
String realDirectory = application.getRealPath(Constant.REAL_DIRECTORY) + "/";

然后建立文件工厂即仓库一个参数表示存放多大后flush，

[java]
view plaincopyprint?

FileItemFactory factory = new DiskFileItemFactory(Constant.SIZE_THRESHOLD,new File(tempDirectory));

ServletFileUpload upload = new ServletFileUpload(factory);

FileItemFactory factory = new DiskFileItemFactory(Constant.SIZE_THRESHOLD,new File(tempDirectory));
ServletFileUpload upload = new ServletFileUpload(factory);

2.对上传的文件进行设定

[java]
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upload.setSizeMax(500*1024*1024);//设置该次上传最大值为500M

upload.setSizeMax(500*1024*1024);//设置该次上传最大值为500M

3,.解析请求正文，获取上传文件，不抛出异常则写入真是路径

[java]
view plaincopyprint?

List<FileItem> list = upload.parseRequest(request);

Iterator<FileItem> iter = list.iterator();
while (iter.hasNext()) {

FileItem item = iter.next();
//item.isFormField()用来判断当前对象是否是file表单域的数据 如果返回值是true说明不是 就是普通表单域

if(item.isFormField()){

System.out.println(
"普通表单域" +item.getFieldName());
System.out.println(item.getString("utf-8"));

}else{
//System.out.println("file表单域" + item.getFieldName());

/*
* 只有file表单域才将该对象中的内容写到真实文件夹中

*/
String lastpath = item.getName();//获取上传文件的名称

lastpath = lastpath.substring(lastpath.lastIndexOf("."));

String filename = UUID.randomUUID().toString().replace("-",
"") + lastpath;
item.write(new File(realDirectory+filename));

List<FileItem> list = upload.parseRequest(request);
Iterator<FileItem> iter = list.iterator();
while (iter.hasNext()) {
FileItem item = iter.next();
//item.isFormField()用来判断当前对象是否是file表单域的数据  如果返回值是true说明不是 就是普通表单域
if(item.isFormField()){
System.out.println( "普通表单域" +item.getFieldName());
System.out.println(item.getString("utf-8"));

}else{
//System.out.println("file表单域" + item.getFieldName());
/*
* 只有file表单域才将该对象中的内容写到真实文件夹中
*/
String lastpath = item.getName();//获取上传文件的名称
lastpath = lastpath.substring(lastpath.lastIndexOf("."));
String filename = UUID.randomUUID().toString().replace("-", "") + lastpath;
item.write(new File(realDirectory+filename));