Class NumberTool

java.lang.Object
org.apache.velocity.tools.generic.SafeConfig
org.apache.velocity.tools.generic.LocaleConfig
org.apache.velocity.tools.generic.FormatConfig
org.apache.velocity.tools.generic.NumberTool
All Implemented Interfaces:
Serializable
@DefaultKey("number") public class NumberTool extends FormatConfig implements Serializable

Tool for working with Number in Velocity templates. It is useful for accessing and formatting arbitrary Number objects. Also the tool can be used to retrieve NumberFormat instances or make conversions to and from various number types.

Example uses:
 $myNumber                   -gt; 13.55
 $number.format($myNumber)   -gt; 13.6
 $number.currency($myNumber) -gt; $13.55
 $number.integer($myNumber)  -gt; 13

Example tools.xml config (if you want to use this with VelocityView):
<tools>
  <toolbox scope="application">
    <tool class="org.apache.velocity.tools.generic.MathTool"/>
  </toolbox>
</tools>

This tool is entirely threadsafe, and has no instance members. It may be used in any scope (request, session, or application). As such, the methods are highly interconnected, and overriding key methods provides an easy way to create subclasses that use a non-default format or locale.

Since:
VelocityTools 1.2
Version:
$Id$
Author:
Nathan Bubna, Mike Kienenberger
See Also:

  • Constructor Details

    • NumberTool

      public NumberTool()

  • Method Details

    • format

      public String format(Object obj)
      Converts the specified object to a number and formats it according to the pattern or style returned by FormatConfig.getFormat().
      Parameters:
      obj - the number object to be formatted
      Returns:
      the specified number formatted as a string
      See Also:

    • currency

      public String currency(Object obj)
      Convenience method equivalent to $number.format("currency", $foo).
      Parameters:
      obj - the number object to be formatted
      Returns:
      the specified number formatted as a currency
      Since:
      VelocityTools 1.3

    • integer

      public String integer(Object obj)
      Convenience method equivalent to $number.format("integer", $foo).
      Parameters:
      obj - the number object to be formatted
      Returns:
      the specified number formatted as an integer
      Since:
      VelocityTools 1.3

    • number

      public String number(Object obj)
      Convenience method equivalent to $number.format("number", $foo).
      Parameters:
      obj - the number object to be formatted
      Returns:
      the specified number formatted as a number
      Since:
      VelocityTools 1.3

    • percent

      public String percent(Object obj)
      Convenience method equivalent to $number.format("percent", $foo).
      Parameters:
      obj - the number object to be formatted
      Returns:
      the specified number formatted as a percentage
      Since:
      VelocityTools 1.3

    • format

      public String format(String format, Object obj)
      Converts the specified object to a number and returns a formatted string representing that number in the locale returned by LocaleConfig.getLocale().
      Parameters:
      format - the formatting instructions
      obj - the number object to be formatted
      Returns:
      a formatted string for this locale representing the specified number or null if the parameters are invalid
      See Also:

    • format

      public String format(String format, Object obj, Locale locale)
      Converts the specified object to a number and returns a formatted string representing that number in the specified Locale.
      Parameters:
      format - the custom or standard pattern to be used
      obj - the number object to be formatted
      locale - the Locale to be used when formatting
      Returns:
      a formatted string representing the specified number or null if the parameters are invalid

    • getNumberFormat

      public NumberFormat getNumberFormat(String format, Locale locale)
      Returns a NumberFormat instance for the specified format and Locale. If the format specified is a standard style pattern, then a number instance will be returned with the number style set to the specified style. If it is a custom format, then a customized NumberFormat will be returned.
      Parameters:
      format - the custom or standard formatting pattern to be used
      locale - the Locale to be used
      Returns:
      an instance of NumberFormat
      See Also:

    • toNumber

      public Number toNumber(Object obj)
      Converts an object to an instance of Number using the format returned by FormatConfig.getFormat() and the Locale returned by LocaleConfig.getLocale() if the object is not already an instance of Number.
      Parameters:
      obj - the number to convert
      Returns:
      the object as a Number or null if no conversion is possible

    • toNumber

      public Number toNumber(String format, Object obj)
      Converts an object to an instance of Number using the specified format and the Locale returned by LocaleConfig.getLocale() if the object is not already an instance of Number.
      Parameters:
      format - - the format the number is in
      obj - - the number to convert
      Returns:
      the object as a Number or null if no conversion is possible
      See Also:

    • toNumber

      public Number toNumber(String format, Object obj, Locale locale)
      Converts an object to an instance of Number using the specified format and Locale if the object is not already an instance of Number.
      Parameters:
      format - - the format the number is in
      obj - - the number to convert
      locale - - the Locale
      Returns:
      the object as a Number or null if no conversion is possible
      See Also:

    • toBoolean

      public Boolean toBoolean(Object value)
      Converts an object to an instance of Boolean if the object is not already an instance of Boolean.
      Parameters:
      value - the object to be converted
      Returns:
      a Boolean object for the specified value or null if the value is null or the conversion failed