private PutCommand convert2PutCommand(final String topic, final int partition, final byte[] data, final int flag,
            int checkSum) {
        return new PutCommand(topic, partition, data, flag, checkSum, null, 0);
    }
Set the response headers. This method is called to set the response
headers such as content type and content length. May be extended to add
additional headers.

@param response
@param resource
@param mimeType
metamorphosis-server-wrapper/src/main/java/com/taobao/metamorphosis/http/processor/MetamorphosisOnJettyProcessor.java