Web service Java com VRaptor para gerar o stream dos jaspers para o Jacad3

conf.properties

#algum diretório seguro.
reports.builded.dir=/home/carlos/reports-temp/

#um hash aleatório.
reports.hash=032rh204nacm9f4-2d3k-9f53-kkc994jn4n

ReportServiceController.java

package com.wp.carlos4web.services.controllers;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.net.URLConnection;
import java.util.Properties;

import br.com.caelum.vraptor.Get;
import br.com.caelum.vraptor.Resource;
import br.com.caelum.vraptor.interceptor.download.Download;
import br.com.caelum.vraptor.interceptor.download.FileDownload;

@Resource
public class ReportServiceController {

	@Get("/services/reports-builded/{report}/{hash}/")
	public Download download(String report, String hash){
		
		Properties conf = getConfigProperties();
		
		if(conf.getProperty("reports.hash").equals(hash)){
			String path = conf.getProperty("reports.builded.dir") + report;
			
			File jasper = new File(path);
			
			String mime = URLConnection.guessContentTypeFromName(jasper.getAbsolutePath());
			
			return new FileDownload(jasper, mime, jasper.getName(), true);
		}
		else{
			throw new IllegalArgumentException("Hash de segurança incorreto.");
		}
	}

	private Properties getConfigProperties() {
		Properties properties = new Properties();
		try {
			InputStream in = Thread.currentThread().getContextClassLoader().getResourceAsStream("conf.properties");
			properties.load(in);
			
			return properties;
			
		} catch (FileNotFoundException e) {
			e.printStackTrace();
			return null;
		} catch (IOException e) {
			e.printStackTrace();
			return null;
		}
	}
}