Valaid Identifiers

InvoiceApp        $orderTotal            i
Invoice           _orderTotal            x
InvoiceApp2       input_string           TITLE
subtotal          _get_total             MONTHS_PER_YEARS
discountPercent   $_64_valid


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The rule for naming an identifier


.Start each identifier with a letter, underscore, 
or dollar sign. Use letters, dollar signs, 
underscores, or digits for subsequent characters.

.Use up to 255 characters.
.Don't use Java keywords.


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Keywords


boolean   if   interface  class   true
char      else package    volatile  false
byte      final switch    while   throws
float     private  case   return  native
void      protected  break    throw    implements
short     public   default    try      import
double    static   for        catch    synchronized
int       new      continue   finally  const
long      this     do         transient   goto
abstract  super    extends    instanceof  null


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