question: return the content-length header or -1 if unknown . concode_field_sep String CONTENT_LENGTH concode_elem_sep String ACK concode_elem_sep Map<String,List<String>> headers concode_elem_sep String LOGIN concode_elem_sep String SERVER concode_elem_sep String SESSION concode_elem_sep String PASSCODE concode_elem_sep String HEARTBEAT concode_elem_sep long serialVersionUID concode_elem_sep String HOST concode_elem_sep String MESSAGE_ID concode_elem_sep String DESTINATION concode_elem_sep String CONTENT_TYPE concode_elem_sep String ID concode_elem_sep String SUBSCRIPTION concode_elem_sep String RECEIPT_ID concode_elem_sep String RECEIPT concode_field_sep void setHeartbeat concode_elem_sep void setContentLength concode_elem_sep void setServer concode_elem_sep boolean isHeartbeatEnabled concode_elem_sep void setSubscription concode_elem_sep boolean containsValue concode_elem_sep List<String> put concode_elem_sep void setPasscode concode_elem_sep String getFirst concode_elem_sep void setId concode_elem_sep void setContentType concode_elem_sep String getHost concode_elem_sep long[] getHeartbeat concode_elem_sep String getServer concode_elem_sep void add concode_elem_sep String getReceiptId concode_elem_sep Set<Entry<String,List<String>>> entrySet concode_elem_sep boolean containsKey concode_elem_sep void setMessageId concode_elem_sep String getPasscode concode_elem_sep int size concode_elem_sep void setReceipt concode_elem_sep MimeType getContentType concode_elem_sep String getDestination concode_elem_sep void setAck concode_elem_sep Collection<List<String>> values concode_elem_sep String getId concode_elem_sep String getReceipt concode_elem_sep void setDestination concode_elem_sep List<String> remove concode_elem_sep String getMessageId concode_elem_sep int hashCode concode_elem_sep List<String> get concode_elem_sep void putAll concode_elem_sep void setSession concode_elem_sep String getAck concode_elem_sep String getSubscription concode_elem_sep void setAll concode_elem_sep Set<String> keySet concode_elem_sep void setReceiptId concode_elem_sep void setHost concode_elem_sep void set concode_elem_sep boolean isEmpty concode_elem_sep void clear concode_elem_sep Map<String,String> toSingleValueMap concode_elem_sep String getLogin concode_elem_sep void setLogin concode_elem_sep boolean equals concode_elem_sep StompHeaders readOnlyStompHeaders concode_elem_sep String toString concode_elem_sep String getSession
target: long function ( ) { String loc0 = getFirst ( CONTENT_LENGTH ) ; return ( loc0 != null ? Long . parseLong ( loc0 ) : - 1 ) ; }