Here's how to get static resources minified and gzipped. Most addons and plugins I've seen don't handle static resources. Stick this file anywhere in the classpath (I put it in "util" directory) and stick the play.plugins file into your conf directory.

play.plugins

1003:util.StaticGzipPlugin

StaticGzipPlugin.java

package util;

import com.google.common.io.Files;
import play.Logger;
import play.Play;
import play.PlayPlugin;
import play.libs.MimeTypes;
import play.mvc.Http;
import play.utils.Utils;
import play.vfs.VirtualFile;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.nio.charset.Charset;
import java.util.Date;

import static org.jboss.netty.handler.codec.http.HttpHeaders.Names.*;
import static util.Compression.*;

public class StaticGzipPlugin extends PlayPlugin {

    @Override
    public boolean serveStatic(VirtualFile file, Http.Request request, Http.Response response) {
        try {
            final File localFile = file.getRealFile();

            String contentType = MimeTypes.getContentType(localFile.getName(), "text/plain");
            // ignore images, I was having trouble when gzipping them. They probably don't need it anyway.
            if (contentType.contains("image")) return false;
            response.setContentTypeIfNotSet(contentType);
            response = addEtag(request, response, localFile);

            // minify
            String content = minify(request, response, localFile);

            // gzip only if supported and not excluded
            if (isGzipSupported(request) && !isExcludedAction(request)) {
                final ByteArrayOutputStream gzip = getGzipStream(content);
                // set response header
                response.setHeader("Content-Encoding", "gzip");
                response.setHeader("Content-Length", gzip.size() + "");
                response.out = gzip;
                return true;
            } else {
                response.out = new ByteArrayOutputStream(content.length());
                response.out.write(content.getBytes());
                return true;
            }
        } catch (Exception e) {
            Logger.error(e, "Error when Gzipping response: %s", e.getMessage());

        }
        return false;
    }

    private String minify(Http.Request request, Http.Response response, File file) throws IOException {
        String content = Files.toString(file, Charset.defaultCharset());
        if (!isExcludedAction(request)) {
            // select compression method by contentType
            if (response.contentType.contains("text/html")) {    // could be "text/html; charset=utf-8"
                return Compression.compressHTML(content);
            } else if (response.contentType.contains("text/xml")) {
                return Compression.compressXML(content);
            } else if (response.contentType.contains("text/css")) {
                return Compression.compressCSS(content);
            } else if (response.contentType.contains("text/javascript")
                    || response.contentType.contains("application/javascript")) {
                return Compression.compressJS(content);
            }
        }
        return content;
    }

    private static Http.Response addEtag(Http.Request request, Http.Response response, File file) {
        if (Play.mode == Play.Mode.DEV) {
            response.setHeader(CACHE_CONTROL, "no-cache");
        } else {
            String maxAge = Play.configuration.getProperty("http.cacheControl", "3600");
            if (maxAge.equals("0")) {
                response.setHeader(CACHE_CONTROL, "no-cache");
            } else {
                response.setHeader(CACHE_CONTROL, "max-age=" + maxAge);
            }
        }
        boolean useEtag = Play.configuration.getProperty("http.useETag", "true").equals("true");
        last = (file.lastModified() / 1000) * 1000
        final String etag = "\"" + last + "-" + file.hashCode() + "\"";
        if (!request.isModified(etag, last)) {
            if (request.method.equals("GET")) {
                response.status = Http.StatusCode.NOT_MODIFIED;
            }
            if (useEtag) {
                response.setHeader(ETAG, etag);
            }
        } else {
            response.setHeader(LAST_MODIFIED, Utils.getHttpDateFormatter().format(new Date(last)));
            if (useEtag) {
                response.setHeader(ETAG, etag);
            }
        }
        return response;
    }

}

GITHUB COMMENTING SYSTEM

ლ(ಠ益ಠლ)

Y U NO WORK CORRECTLY?

this doesn't compile

"this doesn't compile"
It has dependencies. Look at the play-minifymod. You should find everything you need to compile this.

what the heck! with Play 2.0....
response.setHeader .... should be " response().setHeader ... " I spent 15 minutes trying to debug that bad compile!
On other thoughts was that on purpose??????

@manish333999 you spent 15 minutes debugging something that wouldn't compile?

This was written for Play 1.2.4 - I haven't tried it with Play 2.

Looks like the addEtag() method causes problems with Safari. Be careful with it, or disable it until I can figure out a fix: http://stackoverflow.com/questions/16824862/heroku-hosted-html-times-out-after-1-minute-on-safari-only-every-second-time