i've used following code, it works now.
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String[] pool_names = { "test_pool" };
iControl.LocalLBLBMethod[] lb_methods = new iControl.LocalLBLBMethod[1];
lb_methods[0] = iControl.LocalLBLBMethod.LB_METHOD_ROUND_ROBIN;
CommonIPPortDefinition[][] membersToAdd = new CommonIPPortDefinition[1][1];
CommonIPPortDefinition member1 = new CommonIPPortDefinition();
member1.setAddress("10.10.10.10");
member1.setPort(80);
membersToAdd[0][0] = member1;
m_interfaces.getLocalLBPool().create(pool_names, lb_methods,membersToAdd);