package myapp;

import java.io.IOException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.util.*;


public class ListServlet extends HttpServlet {
  InputOutPut io=new InputOutPut();

  @Override
  public void doGet(HttpServletRequest req, HttpServletResponse resp)
      throws IOException {
    resp.setContentType("text/plain");
    List<String> list=new ArrayList<>();
    list.add("String in list");
    io.write(list);
    resp.getWriter().println(io.read().get(0));
  }
}

@@ -492,24 +492,33 @@
  in list%22);%0A
+    try%7B%0A
     io.write
@@ -573,14 +573,103 @@
 et(0));%0A
+    %7D%0A    catch(Exception e)%7B%0A      resp.getWriter().println(e.printStackTrace());%0A    %7D%0A
   %7D%0A%7D%0A

Update ListServlet.java