有一个Servlet,它从客户端接受文件并将它们存储在文件夹中。 现在必须列出该文件夹中的文件并创建指向它们的链接(即,单击文件名,然后从您那里下载文件)。
现在只输出文本形式的文件列表。如何创建指向它们的链接?我读到了这一点,足以暴露标题了,但是如何完成和尚未找到。 示例代码:
public class FileListServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
public FileListServlet() {
super();
}
protected void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {
String param = "/dirs";
PrintWriter w = res.getWriter();
res.setContentType("text/html");
String root="/dirs";
java.io.File dir = new java.io.File(root);
File[] fileList = dir.listFiles();
w.println("<H2><FONT COLOR=TEAL>" + "Total number of files in the choosen directory - " +
fileList.length + "</FONT></H2>");
w.println("<H3><FONT COLOR=PURPLE>" +
"Directory path - " + param + "</FONT></H3><HR>");
w.println("<TABLE BORDER=0 CELLSPACING=5>");
for(int i = 0; i < fileList.length; i++)
printName(fileList[i], w);
w.println("</TABLE><HR>");
}
private void printName(File name, PrintWriter output)
{
String type = name.isDirectory()
? " (Directory)" : " (File)";
output.println("<TR><TD>" + type + "</TD><TD><FONT COLOR=BLUE>"
+ name.getName() + "</FONT></TD></TR>");
}
public String getServletInfo()
{
return "This servlet shows a content of a directory" +
"mentioned in dirToShow parameter or property.";
}
}
答案 0 :(得分:0)
我解决了我的问题。万一有人需要它,或者有人知道更美好的方式。
import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class FileListServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
public FileListServlet() {
super();
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
PrintWriter printWriter = response.getWriter();
response.setContentType("text/html");
File currentFolder = new File(".");
File workingFolder = new File(currentFolder, "Sorted files");
String root = workingFolder.getAbsolutePath();
java.io.File dir = new java.io.File(root);
File[] fileList = dir.listFiles();
printWriter.println("<H2><FONT COLOR=TEAL>" + "Total number of files in the choosen directory - " +
fileList.length + "</FONT></H2>");
printWriter.println("<H3><FONT COLOR=PURPLE>" +
"Directory path - " + root + "</FONT></H3><HR>");
printWriter.println("<TABLE BORDER=0 CELLSPACING=5>");
for(int i = 0; i < fileList.length; i++) {
printName(fileList[i], printWriter);
}
printWriter.println("</TABLE><HR>");
}
private void printName(File file, PrintWriter output)
{
System.out.println(file.getName());
output.println("<tr><td><a href=\"https://Upload/DownloadServlet?name="
+file.getName()+"\">" + file.getName() + "</a></td></tr>" );
}
public String getServletInfo()
{
return "This servlet shows a content of a directory" +
"mentioned in dirToShow parameter or property.";
}
}
和DownloadServlet
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;
/**
* Servlet implementation class DownloadServlet
*/
public class DownloadServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#HttpServlet()
*/
public DownloadServlet() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
String name = request.getParameter("name");
String fileType = "multipart/form-data";
response.setContentType(fileType);
response.setHeader("Content-disposition", "attachment; filename=" + name);
File currentFolder = new File(".");
File workingFolder = new File(currentFolder, "Sorted files");
String root = workingFolder.getAbsolutePath();
File file = new File(root + File.separator + name);
OutputStream output = response.getOutputStream();
FileInputStream input = new FileInputStream(file);
byte[] buffer = new byte[4096];
int lenght;
while( ( lenght = input.read(buffer) ) > 0 ) {
output.write(buffer, 0, lenght);
}
input.close();
output.flush();
output.close();
response.getOutputStream().flush();
response.getOutputStream().close();
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
doGet(request, response);
}
}