DDR爱好者之家 Design By 杰米

本文实例为大家分享了Android九宫格图片展示的具体代码,供大家参考,具体内容如下

由于存储空间,对一般用户而言,就是用来操作存储文件的,所以这两天,特意看了一下windows下用servlet实现文件上传、下载和删除,下面是详细代码说明

上传:

用的是commons-fileupload-1.2.2.jar和commons-io-2.0.1.jar组件,可以去apache官网上去下载,然后放到WebRoot/WEB-INF/lib目录下 

upload.html

 <html> 
<head> 
  <meta http-equiv="Content-Type" content="text/html; charset=GBK"> 
  <title>File upload</title> 
</head> 
<body> 
<!-- action="fileupload"对应web.xml中<servlet-mapping>中<url-pattern>的设置.--> 
<!-- 必须是multipart的表单数据,才能完整的传递文件数据 --> 
  <form name="myform" action="fileupload" method="post" 
    enctype="multipart/form-data"> 
    File:<br> 
    <input type="file" name="myfile"><br> 
    <br> 
    <input type="submit" name="submit" value="Commit"> 
  </form> 
</body> 
</html> 

web.xml里加上下面几行:

<servlet> 
 <servlet-name>Upload</servlet-name> 
 <servlet-class>am.demo.Upload</servlet-class> 
 </servlet> 
 <servlet-mapping> 
 <servlet-name>Upload</servlet-name> 
 <url-pattern>/fileupload</url-pattern> 
 </servlet-mapping> 

src目录下新建文件Upload.java:

package am.demo; 
 
import java.io.File; 
import java.io.IOException; 
import java.util.Iterator; 
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.disk.DiskFileItemFactory; 
import org.apache.commons.fileupload.servlet.ServletFileUpload; 
 
@SuppressWarnings("serial") 
public class Upload extends HttpServlet { 
  private String uploadPath = "d://temp"; // 上传文件的目录 
 
  @SuppressWarnings("unchecked") 
  public void doPost(HttpServletRequest request, HttpServletResponse response) 
      throws IOException, ServletException { 
    try { 
      // Create a factory for disk-based file items 
      DiskFileItemFactory factory = new DiskFileItemFactory(); 
 
 
      // Create a new file upload handler 
      ServletFileUpload upload = new ServletFileUpload(factory); 
 
 
      List<FileItem> items = upload.parseRequest(request);// 得到所有的文件 
      Iterator<FileItem> i = items.iterator(); 
      while (i.hasNext()) { 
        FileItem fi = (FileItem) i.next(); 
        String fileName = fi.getName(); 
        if (fileName != null) { 
          File fullFile = new File(fi.getName()); 
          File savedFile = new File(uploadPath, fullFile.getName()); 
          fi.write(savedFile); 
        } 
      } 
       
      response.setContentType("text/html;charset=GBK");  
      response.getWriter().print( 
      "<mce:script language='javascript'><!-- 
alert('上传成功');window.location.href='index.jsp'; 
// --></mce:script>"); 
    } catch (Exception e) { 
      // 可以跳转出错页面 
      e.printStackTrace(); 
    } 
  } 
 
  public void init() throws ServletException { 
    File uploadFile = new File(uploadPath); 
    if (!uploadFile.exists()) { 
      uploadFile.mkdirs(); 
    } 
  } 
} 

再看下载Downlaod.java:

package am.demo; 
 
import java.io.File; 
import java.io.FileInputStream; 
import java.io.IOException; 
import java.io.OutputStream; 
 
import javax.servlet.ServletException; 
import javax.servlet.http.HttpServlet; 
import javax.servlet.http.HttpServletRequest; 
import javax.servlet.http.HttpServletResponse; 
 
@SuppressWarnings("serial") 
public class Download extends HttpServlet { 
  public void doGet(HttpServletRequest request, HttpServletResponse response) 
      throws IOException, ServletException { 
 
 
    String aFileName = new String(request.getParameter("name").getBytes( 
        "iso8859-1"), "gbk"); 
 
    File fileLoad = new File("d:/temp", aFileName); 
 
    FileInputStream in = null; // 输入流 
    OutputStream out = response.getOutputStream(); 
    byte b[] = new byte[1024]; 
 
    try { 
 
       response.setContentType("application/x-msdownload;"); 
 
      response.setHeader("Content-disposition", "attachment; filename=" 
          + new String(aFileName.getBytes("GBK"), "ISO-8859-1")); 
 
      // download the file. 
      in = new FileInputStream(fileLoad); 
      int n = 0; 
      while ((n = in.read(b)) != -1) { 
        out.write(b, 0, n); 
      } 
 
    } catch (Throwable e) { 
      e.printStackTrace(); 
    } finally { 
      try { 
        in.close(); 
        out.close(); 
      } catch (Throwable e) { 
        e.printStackTrace(); 
      } 
    } 
  } 
 
  public void doPost(HttpServletRequest request, HttpServletResponse response) 
      throws IOException, ServletException { 
    doGet(request, response); 
  } 
 
} 

删除Delete.java:

package am.demo; 
 
import java.io.File; 
import java.io.FileNotFoundException; 
import java.io.IOException; 
 
import javax.servlet.ServletException; 
import javax.servlet.http.HttpServlet; 
import javax.servlet.http.HttpServletRequest; 
import javax.servlet.http.HttpServletResponse; 
 
@SuppressWarnings("serial") 
public class Delete extends HttpServlet { 
 
  public void doGet(HttpServletRequest request, HttpServletResponse response) 
      throws FileNotFoundException, IOException { 
 
    String aFileName = new String(request.getParameter("name").getBytes( 
        "iso8859-1"), "gbk"); 
 
    File file = new File("d:/temp", aFileName); 
 
    response.setContentType("text/html;charset=GBK"); 
 
    if (!file.isDirectory()) { 
      file.delete(); 
      response.getWriter().print( 
        "<mce:script language='javascript'><!-- 
alert('删除成功');window.location.href='index.jsp'; 
// --></mce:script>"); 
    } else { 
 
    } 
 
  } 
 
  public void doPost(HttpServletRequest request, HttpServletResponse response) 
      throws IOException, ServletException { 
    doGet(request, response); 
  } 
} 

 因为ubuntu server是黑屏,本人用的是ubuntu server10.04,不方便用浏览器来查看文件,因为没有图形界面,也不方便调试,所以可以先在windows上测试通过,然后把相应文件拷到ubuntu server中的tomcat相应目录下,可以通过samba来传文件,但遇到一个问题,就是中文乱码的问题,因为在开始安装时,选的是英文,后面用网上的一些办法,还是没有解决中文乱码的问题,有知道的大侠,还烦请转告。

以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持。

DDR爱好者之家 Design By 杰米
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DDR爱好者之家 Design By 杰米