Returns true if the argument contains a number

      
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 */

import java.security.SecureRandom;
import java.util.Random;

public class StringUtils
{


  /**
   *  Returns true, if the argument contains a number, otherwise false.
   *  In a quick test this is roughly the same speed as Integer.parseInt()
   *  if the argument is a number, and roughly ten times the speed, if
   *  the argument is NOT a number.
   *
   *  @since 2.4
   *  @param s String to check
   *  @return True, if s represents a number.  False otherwise.
   */

  public static boolean isNumber( String s )
  {
      if( s == null ) return false;

      if( s.length() > 1 && s.charAt(0) == '-' )
          s = s.substring(1);

      for( int i = 0; i < s.length(); i++ )
      {
          if( !Character.isDigit(s.charAt(i)) )
              return false;
      }

      return true;
  }
}

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Returns true if the argument contains a number : String Parser « Data Type « Java

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