Servlet 3.0 container's has standard support for multipart data. First you should be writing a HTML page which takes the file input along with other input parameters.
<form action="uploadservlet" method="post" enctype="multipart/form-data">
<input type="text" name="name" />
<input type="text" name="age" />
<input type="file" name="photo" />
<input type="submit" />
</form>
Now write a UploadServlet which uses the Servlet 3.0 Upload API. Here is the code which demonstrates the usage of API. Fist the servlet handling multipart data should define MultiPartConfig using any of the two approaches:
@MultiPartConfig annotation on Servlet Class- In
web.xml, by adding <multipart-config> entry inside <servlet> definition.
Here is the UploadServlet,
@MultipartConfig
public class UploadServlet extends HttpServlet
{
protected void service(HttpServletRequest request,
HttpServletResponse responst) throws ServletException, IOException
{
Collection<Part> parts = request.getParts();
if (parts.size() != 3) {
//can write error page saying all details are not entered
}
Part filePart = httpServletRequest.getPart("photo");
InputStream imageInputStream = filePart.getInputStream();
//read imageInputStream
filePart.write("somefiepath");
//can also write the photo to local storage
//Read Name, String Type
Part namePart = request.getPart("name");
if(namePart.getSize() > 20){
//write name cannot exceed 20 chars
}
//use nameInputStream if required
InputStream nameInputStream = namePart.getInputStream();
//name , String type can also obtained using Request parameter
String nameParameter = request.getParameter("name");
//Similialrly can read age properties
Part agePart = request.getPart("age");
int ageParameter = Integer.parseInt(request.getParameter("age"));
}
}
If you are not using Sevlet 3.0 Container, you should be truing Apache Commons File Upload. Here are the links for using Apache Commons File Upload:
- Using Apache Commons File Upload
- Apache Commons File Upload Example
References:
- Servlet 3.0 javax.servlet.http.HttpServletRequest API
- Servlet 3.0 javax.servlet.http.Part API
- Uploading File using Servlet 3.0
