Difference between revisions of "Formatting"

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== Introduction ==
 
== Introduction ==
  
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* String formatting can be done using the printf() and the format() methods added in java.io.PrintStream (System.out is a PrintStream)
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* Internally they ise the java.util.Formatter class.
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* Basic format:
  
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printf("format string", argument(s));
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== Format String ==
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* Syntax:
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%[arg_index$][flags][width][.precision] conversion_char
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Arguments within [] are optional. Only the conversion_char is mandatory. The following are the conversion chars:
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* b - boolean
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* c - char
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* d - integer
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* f - floating point
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* s - string
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Optional arguments
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* arg_index is the number of the argument followed by a $. The no starts from 1.
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<syntaxhighlight lang="java5">
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System.out.printf("%2$s , %1$s", Suhrid, Karthik);
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//Prints : Karthik, Suhrid
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</syntaxhighlight>
  
 
[[Category:OCPJP]]
 
[[Category:OCPJP]]

Revision as of 02:13, 8 July 2011

Introduction

  • String formatting can be done using the printf() and the format() methods added in java.io.PrintStream (System.out is a PrintStream)
  • Internally they ise the java.util.Formatter class.
  • Basic format:

printf("format string", argument(s));

Format String

  • Syntax:

%[arg_index$][flags][width][.precision] conversion_char

Arguments within [] are optional. Only the conversion_char is mandatory. The following are the conversion chars:

  • b - boolean
  • c - char
  • d - integer
  • f - floating point
  • s - string

Optional arguments

  • arg_index is the number of the argument followed by a $. The no starts from 1.
System.out.printf("%2$s , %1$s", Suhrid, Karthik);
//Prints : Karthik, Suhrid