Filter to optionally compress response with gzip

Accept a query parameter like isCompressionRequired. If this query param is present, compress the response using gzip. This will ensure less bandwidth usage if field apps are using mobile data.

Sample Code for response filter :-

Inside filter method :-

if (request.getRequestHeaders().getFirst(HttpHeaders.ACCEPT_ENCODING).contains("gzip"))

{ response.getHttpHeaders().add(HttpHeaders.CONTENT_ENCODING, "gzip"); response.setContainerResponseWriter( new Adapter(response.getContainerResponseWriter())); }

private static final class Adapter implements ContainerResponseWriter {
private final ContainerResponseWriter crw;

private GZIPOutputStream gos;

Adapter(ContainerResponseWriter crw)

{ this.crw = crw; }

public OutputStream writeStatusAndHeaders(long contentLength, ContainerResponse response) throws IOException

{ gos = new GZIPOutputStream(crw.writeStatusAndHeaders(-1, response)); return gos; }

public void finish() throws IOException

{ gos.finish(); crw.finish(); }

}