Putting all together

import freemarker.template.*;
import java.util.*;
import java.io.*;

public class Test {

    public static void main(String[] args) throws Exception {
        
        /* ------------------------------------------------------------------------ */    
        /* You should do this ONLY ONCE in the whole application life-cycle:        */    
    
        /* Create and adjust the configuration singleton */
        Configuration cfg = new Configuration(Configuration.VERSION_2_3_22);
        cfg.setDirectoryForTemplateLoading(new File("/where/you/store/templates"));
        cfg.setDefaultEncoding("UTF-8");
        cfg.setTemplateExceptionHandler(TemplateExceptionHandler.RETHROW);

        /* ------------------------------------------------------------------------ */    
        /* You usually do these for MULTIPLE TIMES in the application life-cycle:   */    

        /* Create a data-model */
        Map root = new HashMap();
        root.put("user", "Big Joe");
        Map latest = new HashMap();
        root.put("latestProduct", latest);
        latest.put("url", "products/greenmouse.html");
        latest.put("name", "green mouse");

        /* Get the template (uses cache internally) */
        Template temp = cfg.getTemplate("test.ftl");

        /* Merge data-model with template */
        Writer out = new OutputStreamWriter(System.out);
        temp.process(root, out);
        // Note: Depending on what `out` is, you may need to call `out.close()`.
        // This is usually the case for file output, but not for servlet output.
    }
}