Run create/drop DB2 database commands for a speci

db2 CREATE DATABASE XYZ

db2 DROP   DATABASE XYZ

These db2 commands which doesn't provide support to specify username/password while executing on db2cmd/db2clp for a specific user other than machine logged-in user. Hence result a exception

"SQL1092N The requested command or operation failed because the user ID does not have the authority to perform the requested command or operation."

And when the same commands run as by choosing 'Run as different user', it works properly.

But I need to use same mechanism from Java code, but don't know how. Is it possible to open installed db2's clp as a different user form Java code??
Is it possible to associate username/password in create/drop commands?

From the CLP you can first ATTACH to the instance using whatever user ID you need, and then issue the CREATE DATABASE command.

If the instance is running on your local machine, you just attach like this:

$ db2 attach to db2inst1 user db2inst1
Enter current password for db2inst1: 

   Instance Attachment Information

 Instance server        = DB2/LINUXX8664 9.7.5
 Authorization ID       = DB2INST1
 Local instance alias   = DB2INST1

If the instance is running on a remote server, you attach to the "node name" that you have defined in your database catalog:

$ db2 list db directory

 System Database Directory

 Number of entries in the directory = 1

Database 1 entry:

 Database alias                       = SAMPLE
 Database name                        = SAMPLE
 Node name                            = SRV01
 Database release level               = d.00
 Comment                              =
 Directory entry type                 = Remote
 Catalog database partition number    = -1
 Alternate server hostname            =
 Alternate server port number         =

In this example, the Node Name shown in the output from list database directory is SRV01, so you would attach using: db2 attach to srv01 user <username>.