Ninf-G Java Client API version4 FAQ

Q1, Can I use Java CoG kit as GT library?
A1, No.
    Ninf-G Java Client API version4 requires GT4(Java WS Core).
    Java CoG kit doesn't work with Ninf-G Java Client.

Q2, Can I limit the port range to be used ? 
A2, Yes, A client instantiates two objects, PortManager and GassServer.
    They are created just once for one client.

    Currently, the ports to be used by those objects are dynamically
    assigned to any ports, but you can set the port range in 
    $HOME/.globus/cog.properties like the following.   
 
    # port range 
      tcp.port.range = 64001,65000

Q3, On Windows, Ninf-G client sometimes fails when it tries to handle
    simultaneous multiple requests.
A3, On Windows, ServerSocket sometimes fails to accept requests for connection
    from Ninf-G Executables when there are many (about 10 or more)
    simultaneous requests.
    This problem does not appears on Linux or Solaris.
    So Please use Linux or Solaris for large-scale client applications.

Q4, On Windows, Ninf-G Executables can't connect back to Ninf-G Client.
A4, Set "loglevel" of <CLIENT> section in your client configuration file to 5,
    And check the RSL string of "arguments".
    There is a "--client=..." in RSL string, it indicates where to connect
    back from Ninf-G Executable.  Wrong location may be specified.
    In order to avoid this, you can specify the location where to
    connect back in "hostname" attribute in <CLIENT> section of your
    client configuration file.  Following is an example of the description.

    ===== example of client configuration file =====
      <CLIENT>
        hostname 10.0.0.1
      </CLIENT>
    ===== example of client configuration file =====

Q5, Does Ninf-G Java Client library provide all functions which are
    supported by C client library?
A5, No.
    Following functions are not supported on Ninf-G Java Client library.
    + more than 31 arguments for NgGrpcFunctionHandle#call()
      and NgGrpcObjectHandle#invoke().
    + argument stack for NgGrpcFunctionHandle#call()
      and NgGrpcObjectHandle#invoke().
    + following attributes in configuration file will be ignored.
      - "save_sessionInfo" in "<CLIENT>" section
      - "refresh_credential" in "<CLIENT>" section
      - "force_xdr" in "<SERVER>" section
      - "argument_transfer" in "<SERVER>" section
      - "server_timeout" in "<MDS_SERVER>" section

Q6, Can null be specified as an argument of grpc_call() and grpc_invoke()?
A6, Yes.  null can be specified as argument of grpc_call() and grpc_invoke().
    But in this case, you have to specify the type of argument.
    When you specify null as an argument, please see java/diag/NullArgumentTest.java.

Q7, How can I use WS GRAM of GT4?
A7, By default, Ninf-G Java Client uses PreWS GRAM to invoke jobs.
    If you want to use WS GRAM, you have to set <SERVER> "invoke_server"
    to "GT4py".  But "GT4py" does not work on Windows.  If you want to use
    WS GRAM on Windows, you have to use invoke_server "GT4java".
    See ng-4.x.x/utility/invoke_server/gt4java/README for more details.