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student:java:formatting [2018/08/10 13:06] – created bernstdhstudent:java:formatting [2018/08/10 13:09] (current) – bernstdh
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 The static ''%%format()%%'' method in the ''%%String%%'' class is  passed one parameter called a //format string// and then any number  of other parameters. In the above example, the format string is  ''%%"CS%3d"%%'' and the one other parameter  is ''%%course%%''. A format string consists  of ''%%String%%'' literals and //format specifiers//. In the above  example, the format specifier is ''%%%3d%%''. The static ''%%format()%%'' method in the ''%%String%%'' class is  passed one parameter called a //format string// and then any number  of other parameters. In the above example, the format string is  ''%%"CS%3d"%%'' and the one other parameter  is ''%%course%%''. A format string consists  of ''%%String%%'' literals and //format specifiers//. In the above  example, the format specifier is ''%%%3d%%''.
  
-Format specifiers have the following syntaxcommand_syntax.+Format specifiers have the following syntax. 
 + 
 +|  %[//flags//][//width//][.//precision//]//conversion//  |
  
-%[//flags//][//width//][.//precision//]//conversion// 
 Common values of //conversion// include  ''%%b%%'' for ''%%boolean%%'',  ''%%c%%'' for ''%%char%%'',  ''%%d%%'' for ''%%int%%'',  ''%%e%%'' for ''%%double%%'' in scientific notation,  ''%%f%%'' for ''%%double%%'', and  ''%%s%%'' for ''%%String%%''. Common values of //conversion// include  ''%%b%%'' for ''%%boolean%%'',  ''%%c%%'' for ''%%char%%'',  ''%%d%%'' for ''%%int%%'',  ''%%e%%'' for ''%%double%%'' in scientific notation,  ''%%f%%'' for ''%%double%%'', and  ''%%s%%'' for ''%%String%%''.
  
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 So, for example the format specifier ''%%%8d%%'' indicates an  ''%%int%%'' that will be right-justified in a field of width 8.  Similarly, the format specifier ''%%-%6.2f%%'' indicates a  ''%%double%%'' that will be left-justified in a field of width 6  with 2 places to the right of the decimal point. So, for example the format specifier ''%%%8d%%'' indicates an  ''%%int%%'' that will be right-justified in a field of width 8.  Similarly, the format specifier ''%%-%6.2f%%'' indicates a  ''%%double%%'' that will be left-justified in a field of width 6  with 2 places to the right of the decimal point.
  
-The format string in the invokation of the ''%%format()%%''  method should have the same number of format specifiers as there are  other parameters in the invokation. This is illustrated in the following  example.+The format string in the invocation of the ''%%format()%%''  method should have the same number of format specifiers as there are  other parameters in the invocation. This is illustrated in the following  example.
  
-<code>+<code java>
  int  year = 2017;  int  year = 2017;
  double sales = 1050987.00;  double sales = 1050987.00;
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 </code> </code>
  
- After this code is executed, ''%%s%%'' will contain  ''%%%%Year: 2017, Sales: $ 1,050,987.00%%%%''+After this code is executed, ''%%s%%'' will contain  ''%%%%Year: 2017, Sales: $ 1,050,987.00%%%%''
  
 ==== Printing a Formatted String ==== ==== Printing a Formatted String ====
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-<code>+<code java>
  int  year = 2017;  int  year = 2017;
  double sales = 1050987.00;  double sales = 1050987.00;
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 However, when all you want to do is print a formatted ''%%String%%'',  it is easier to do it in one step, rather than two (i.e., first calling  ''%%format()%%'' and then calling ''%%println()%%''. To accomodate  this, all objects that have a ''%%println()%%'' method also have  a ''%%printf()%%'' method that has the same syntax as the  ''%%format()%%'' method. Hence, the previous example could also be  implemented as follows. However, when all you want to do is print a formatted ''%%String%%'',  it is easier to do it in one step, rather than two (i.e., first calling  ''%%format()%%'' and then calling ''%%println()%%''. To accomodate  this, all objects that have a ''%%println()%%'' method also have  a ''%%printf()%%'' method that has the same syntax as the  ''%%format()%%'' method. Hence, the previous example could also be  implemented as follows.
  
-<code>+<code java>
  int  year = 2017;  int  year = 2017;
  double sales = 1050987.00;  double sales = 1050987.00;