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Background 

        STUTTGART UNIVERSITY OF APPLIED 

SCIENCES 

2.5.2.1 

Configurations 

Configurations comprise a virtual  machine and a minimal set of class  libraries. They 

provide  the  base  functionality  for  a  particular  range  of  devices  that  share  similar 

characteristics,  such  as  network  connectivity  and  memory  footprint.  Currently,  there 

are two J2ME configurations: the Connected Limited Device  Configuration (CLDC) 

and the Connected Device Configuration (CDC). 

2.5.2.2 

Profiles 

To  provide  a  complete  runtime  environment  for  a  specific  device  category  a 

configuration must be combined with a profile, a set of higher level APIs that further 

define  the  application  life cycle  model,  the  user  interface,  and  access  to 

device specific  properties.  A  profile  supports  a  narrower  category  of  devices  within 

the  framework  of  a  chosen  configuration.  A  widely  adopted  example  is  to  combine 

CLDC  with  the  Mobile  Information  Device  Profile  (MIDP)  to  provide  a  complete 

Java  application  environment  for  cell  phones  and  other  devices  with  similar 

capabilities. 

2.5.2.3 

Optional Packages 

The  J2ME  platform  can  be  extended  by  adding  various  optional  packages  to  a 

technology  stack  that  includes  either  CLDC  or  CDC  and  an  associated  profile. 

Created  to  address  very  specific  application  requirements,  optional  packages  offer 

standard  APIs  for  using  both  existing  and  emerging  technologies  such  as  database 

connectivity,  wireless  messaging,  multimedia,  Bluetooth,  and  web  services.  Because 

optional  packages  are  modular,  developers  can  avoid  carrying  the  overhead  of 

unnecessary  functionality  by  including  only  the  packages  of  an  application  actually 

needs. 

2.5.3  Mobile Information Device Profile (MIDP) 

The Mobile Information Device Profile (MIDP) is a key element of J2ME. CLDC and 

MIDP  provide  the  core  application  functionality  required  by  mobile  applications,  in 

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