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javasnmp

Checking if MIB object is DisplayString

I'm using java Mibble library to process MIB files and create MIB implementation for my snmp agent. And have a little problem with that:

There is a DisplayString type that is the representation of OCTET_STRING but can contains only 7bit ASCII chars. There is also type like AdminString that is another represetnation of OCTET_STRING but can contains all ASCII chars.

So my question is: how to distinguish DisplayString (so I can check for chars that are greater then 126 in my implementation) from Admin String? i tried to use MibTypeTag[1] but apparently I don't know HOW to use it (any hints?) and it says that "it is possible to distinguish between types using the same or a similar primitive ASN.1 type representation (such as DisplayString and IpAddress)"

My written english isn't perfect so here's what I would like to do:

if (MibTypeTag == DisplayString) {
   check for chars greater than 126
}
else if (MibTypeTag == AdminString) {
   awesome! nothing to do!
}

Thanks in advance!

[1] http://www.mibble.org/doc/release/api/net/percederberg/mibble/MibType.html

Solution

  • Ok, I resolved this problem.

    I decided not to use getTag() at all - instead I tried this algorithm:

    1. get the type of the object (getType()) and check if it is an instance of StringType

    2. if it is I get reference symbol from it:

      MibTypeSymbol mts = (StringType)myObj.getReferenceSymbol()

    3. Then I convert this MibTypeSymbol to String and compare to "DisplayString"

      mts.toString.equals("DisplayString");

    And - as for now - it is working.

    Mayby this help for someone in the future.

    But mayby someone have better idea?