Download executable file through servlet

Create index.jsp file

<form method="post" action="OpenNotepadServlet">

<input type="submit" value="Open Notepad"/>
</form>

---

Create OpenNotepadServlet.java file

package com.pcc.rnd;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;

import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
* Servlet implementation class OpenNotepadServlet
*/
@WebServlet("/OpenNotepadServlet")
public class OpenNotepadServlet extends HttpServlet {
private static final long serialVersionUID = 1L;

/**
* @see HttpServlet#HttpServlet()
*/
public OpenNotepadServlet() {
super();
}

/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
runNotepad(request,response);
}

/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
runNotepad(request,response);
}

private void runNotepad(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setContentType("application/octet-stream");
response.setHeader("Content-Disposition","attachment;filename=mytest.bat");
StringBuffer sb = new StringBuffer("C:\\Windows\\System32\\notepad.exe");
InputStream in = new ByteArrayInputStream(sb.toString().getBytes("UTF-8"));
ServletOutputStream out = response.getOutputStream();

byte[] outputByte = new byte[4096];
//copy binary contect to output stream
while(in.read(outputByte, 0, 4096) != -1) {
out.write(outputByte, 0, 4096);
}
in.close();
out.flush();
out.close();
}
}