Add httpsession-xml

Fixes #103

samples/httpsession-xml/src/main/java/sample/SessionServlet.java

@@ -0,0 +1,20 @@
+package sample;
+
+import javax.servlet.*;
+import javax.servlet.annotation.*;
+import javax.servlet.http.*;
+import java.io.IOException;
+
+@WebServlet("/session")
+public class SessionServlet extends HttpServlet {
+
+    @Override
+    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+        String attributeName = req.getParameter("attributeName");
+        String attributeValue = req.getParameter("attributeValue");
+        req.getSession().setAttribute(attributeName, attributeValue);
+        resp.sendRedirect(req.getContextPath() + "/");
+    }
+
+    private static final long serialVersionUID = 2878267318695777395L;
+}