code: public static void compressZip(Resource[] sources, Resource target, ResourceFilter filter) throws IOException {
  	ZipOutputStream zos = null;
  	try {
  	    zos = new ZipOutputStream(IOUtil.toBufferedOutputStream(target.getOutputStream()));
  	    compressZip("", sources, zos, filter);
  	}
  	finally {
  	    IOUtil.closeEL(zos);
  	}
      }
docs: compress a source file/directory to a zip file
  
  @param sources
  @param target
  @param filter
  @throws IOException