一 、處理帶說明信息的圖片與處理文件上傳
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String | getContentType() 獲取文檔的類型 Returns the content type passed by the browser or null if not defined. | |
String | getFieldName() 獲取字段的名稱，即name=xxxx Returns the name of the field in the multipart form corresponding to this file item. <input type=”file” name=”img”/> | |
InputStream | getInputStream() Returns an InputStream that can be used to retrieve the contents of the file. | |
String | getName() Returns the original filename in the client's filesystem, as PRovided by the browser (or other client software). 獲取文件名稱。 如果是在IＥ獲取的文件為 c：/aaa/aaa/xxx.jpg –即完整的路徑。 非IE;文件名稱只是 xxx.jpg | |
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long | getSize() 獲取文件大小 相當(dāng)于in.avilivable(); Returns the size of the file item | |
如果你上傳是一普通的文本元素，則可以通過以下方式獲取元素中的數(shù)據(jù) <form enctype=”multipart/form-data”> <input type=”text” name=”name”/> | ||
String | getString() 用于獲取普通的表單域的信息。 Returns the contents of the file item as a String, using the default character encoding.（IOS-8859-1） | |
String | getString(Stringencoding) 可以指定編碼格式 Returns the contents of the file item as a String, using the specified encoding. | |
void | write(Filefile) 直接將文件保存到另一個文件中去。 A convenience method to write an uploaded item to disk. | |
以下文件用判斷一個fileItem是否是file（type=file）對象或是text(type=text|checkbox|radio)對象： | ||
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代碼：
public class UpDescServlet extends HttpServlet {
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.setCharacterEncoding("UTF-8");//可以獲取中文的文件名
String path = getServletContext().getRealPath("/up");
DiskFileItemFactory disk =
new DiskFileItemFactory();
disk.setRepository(new File("d:/a"));
try{
ServletFileUpload up =
new ServletFileUpload(disk);
List<FileItem> list = up.parseRequest(request);
for(FileItem file:list){
//第一步：判斷是否是普通的表單項
if(file.isFormField()){
String fileName = file.getFieldName();//<input type="text" name="desc">=desc
String value = file.getString("UTF-8");//默認(rèn)以ISO方式讀取數(shù)據(jù)
System.err.println(fileName+"="+value);
}else{//說明是一個文件
String fileName = file.getName();
fileName = fileName.substring(fileName.lastIndexOf("http://")+1);
file.write(new File(path+"/"+fileName));
System.err.println("文件名是:"+fileName);
System.err.println("文件大小是："+file.getSize());
file.delete();
}
}
}catch(Exception e){
e.printStackTrace();
}
}
}
二處理文件上傳（性能能夠相對之前提升）
核心點用FileItemIterator it= up.getItemIterator(request);處理文件上傳。
package cn.hx.servlet;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
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.FileItemIterator;
import org.apache.commons.fileupload.FileItemStream;
import org.apache.commons.fileupload.RequestContext;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.apache.commons.fileupload.servlet.ServletRequestContext;
import org.apache.commons.io.FileUtils;
public class FastServlet extends HttpServlet {
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.setCharacterEncoding("UTF-8");
String path = getServletContext().getRealPath("/up");
DiskFileItemFactory disk =
new DiskFileItemFactory();
disk.setRepository(new File("d:/a"));
try{
ServletFileUpload up = new ServletFileUpload(disk);
//以下是迭代器模式
FileItemIterator it= up.getItemIterator(request);
while(it.hasNext()){
FileItemStream item = it.next();
String fileName = item.getName();
fileName=fileName.substring(fileName.lastIndexOf("http://")+1);
InputStream in = item.openStream();
FileUtils.copyInputStreamToFile(in,new File(path+"/"+fileName));
}
}catch(Exception e){
e.printStackTrace();
}
}
}
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