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Quest is a JVM framework for quickly defining both api endpoints and view controllers in a web application

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package org.cinchapi.quest.router;

import java.io.File;
import java.util.Collections;
import java.util.Map;

import com.google.common.collect.Maps;

/**
 * A {@link View} is processed by a {@link Router} to display some front end
 * template.
 * 
 * @author jeffnelson
 * 
 */
public abstract class View extends AbstractRewritableRoute {

    /**
     * An empty collection that should be returned from the {@link #serve()}
     * method if there is no data for the front end template.
     */
    protected final static Map NO_DATA = Collections
            .unmodifiableMap(Maps. newHashMap());

    /**
     * Construct a new instance
     * 
     * @param relativePath
     */
    public View(String relativePath) {
        super(relativePath);
    }

    @Override
    public final Object handle() {
        return template("views" + File.separator + template()).render(
                serve());
    }

    /**
     * The name of the template to display. The View will look in the
     * {@link templates} folder at the root of the working directory for the
     * mustache template with the specified name.
     * 
     * @return the name of the view template (e.g. index.mustache)
     */
    protected abstract String template();

    /**
     * Serve the request and render the view.
     * 
     * Use this method to take care of any logic that determines whether the
     * request can be served (i.e. is it valid? does it need to be redirected?,
     * etc). Ultimately, this method should return any data (encapsulated in a
     * mapping from variable names to values) that the front end
     * {@link #template()} is expecting.
     * 
     * 
     * Return {@link #NO_DATA} if there is none to give to the front end
     * template.
     * 
     * 
     * @return the view data
     */
    protected abstract Map serve();

}