Interface for parsing lines in the HEAD section of an HTTP message.
There are individual methods for parsing a request line, a
status line, or a header line.
The lines to parse are passed in memory, the parser does not depend
on any specific IO mechanism.
Instances of this interface are expected to be stateless and thread-safe.
Checks whether there likely is a protocol version in a line.
This method implements a heuristic to check for a
likely protocol version specification. It does not
guarantee that {@link #parseProtocolVersion} would not
detect a parse error.
This can be used to detect garbage lines before a request
or status line.
param
buffer a buffer holding the line to inspect
param
cursor the cursor at which to check for a protocol version, or
negative for "end of line". Whether the check tolerates
whitespace before or after the protocol version is
implementation dependent.
return
true if there is a protocol version at the
argument index (possibly ignoring whitespace),
false otherwise
Creates a header from a line.
The full header line is expected here. Header continuation lines
must be joined by the caller before invoking this method.
param
buffer a buffer holding the full header line.
This buffer MUST NOT be re-used afterwards, since
the returned object may reference the contents later.
return
the header in the argument buffer.
The returned object MAY be a wrapper for the argument buffer.
The argument buffer MUST NOT be re-used or changed afterwards.
Parses the textual representation of a protocol version.
This is needed for parsing request lines (last element)
as well as status lines (first element).
param
buffer a buffer holding the protocol version to parse
param
cursor the parser cursor containing the current position and
the bounds within the buffer for the parsing operation
