Decompress gsipped http response

Question

Hi, Java developers. I get a response with headers and body as shown below, but when I try to unpack it using the following code, it fails with this exception:

 java.io.IOException: Not in GZIP format

Answer:

 HTTP / 1.1 200 OK
 Content-Type: text / xml;  charset = utf-8
 Content-Encoding: gzip
 Server: Jetty (6.1.x)
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 ╬û? ▓ε? ╞┼ → RtGqè ₧ ójWë ♫ ╩∞j05├╞┘ |> ┘º ∙ ↑ j╪2┐ | = ÷ ²
 eY \ ╛P? # 5wÑqc╙τ ♦ ▓½Θt £ 6q∩? ┌4┼t ♠ ↕ = 7æƒ╙? ╟ | ♂; ║) ∩ ÷ ≈═ ^ ╛ {v⌂┌∞◄> 6ä╝ |

The code:

byte[] b= IOUtils.toByteArray(sock.getInputStream()); ByteArrayInputStream bais = new ByteArrayInputStream(b); GZIPInputStream gzis = new GZIPInputStream(bais); InputStreamReader reader = new InputStreamReader(gzis); BufferedReader in = new BufferedReader(reader); String readed; while ((readed = in.readLine()) != null) { System.out.println("read: "+readed); } 

Please inform.

Thanks,

Pradeep

Answer 1

The MIME header is NOT in GZIP format, it is in plain text. You must read this before you can unpack the stream.

Also, why not just use this:

 InputStream in = sock.getInputStream(); readHeader(in); InputStream zin = new GZIPInputStream(in); 

Answer 2

There are libraries for all of this. You can use, for example, Apache HTTP Components , or you can read it open source to find out what it does. At least read the relevant specification.

Answer 3

The second answer is bmarguiles.

Only the body ( response-body in the RFC) is compressed, so you only need to unpack the part that is after \r\n\r\n .

Generally speaking, you can cut the answer in half with these double CRLFs and only unzip the other half.