package example;

import java.util.*;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import freemarker.template.*;

/**
 * This Servlet does not do anything useful, just prints "Hello World!". The
 * intent is to help you to get started if you want to build your own Controller
 * servlet that uses FreeMarker for the View. For more advanced example, see the
 * 2nd Web application example.
 */
public class HelloServlet extends HttpServlet {
    private Configuration cfg; 
    
    public void init() {
        // Initialize the FreeMarker configuration;
        // - Create a configuration instance
        cfg = new Configuration();
        // - Templates are stoted in the WEB-INF/templates directory of the Web app.
        cfg.setServletContextForTemplateLoading(
                getServletContext(), "WEB-INF/templates");
        // In a real-world application various other settings should be explicitly
        // set here, but for the sake of brevity we leave it out now. See the
        // "webapp2" example for them.
    }
    
    protected void doGet(HttpServletRequest req, HttpServletResponse resp)
        throws ServletException, IOException {
        
        // Build the data-model
        Map root = new HashMap();
        root.put("message", "Hello World!");
        
        // Get the templat object
        Template t = cfg.getTemplate("test.ftl");
        
        // Prepare the HTTP response:
        // - Use the charset of template for the output
        // - Use text/html MIME-type
        resp.setContentType("text/html; charset=" + t.getEncoding());
        Writer out = resp.getWriter();
        
        // Merge the data-model and the template
        try {
            t.process(root, out);
        } catch (TemplateException e) {
            throw new ServletException(
                    "Error while processing FreeMarker template", e);
        }
    }
}