String fileName = "/coverages/" + getCoverage.getCoverageId() + "." + delegate.getFileExtension(format);
// coverages xml structure, which is very close to the DescribeFeatureType output
BodyPart coveragesPart = new MimeBodyPart();
FileReference reference = new FileReference(fileName, delegate.getMimeType(format), delegate.getConformanceClass(format));
final CoverageData coveragesData = new CoverageData(coverage, reference, envelopeDimensionsMapper);
coveragesPart.setDataHandler(new DataHandler(coveragesData, "geoserver/coverages20"));
coveragesPart.setHeader("Content-ID", "wcs");
coveragesPart.setHeader("Content-Type", "application/gml+xml");
multipart.addBodyPart(coveragesPart);