Package org.apache.velocity.tools.generic

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:

java.io.Serializable

@DefaultKey("number")
public class NumberTool
extends FormatConfig
implements java.io.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:

Serialized Form

Field Summary

Fields inherited from class org.apache.velocity.tools.generic.FormatConfig

DEFAULT_FORMAT, FORMAT_KEY

Fields inherited from class org.apache.velocity.tools.generic.LocaleConfig

DEFAULT_LOCALE

Fields inherited from class org.apache.velocity.tools.generic.SafeConfig

LOCK_CONFIG_KEY, log, LOGGER_NAME_KEY, SAFE_MODE_KEY, USE_CLASS_LOGGER_KEY

Constructor Summary

Constructors

Constructor	Description
NumberTool()

Method Summary

Modifier and Type	Method	Description
java.lang.String	currency(java.lang.Object obj)	Convenience method equivalent to $number.format("currency", $foo).
java.lang.String	format(java.lang.Object obj)	Converts the specified object to a number and formats it according to the pattern or style returned by FormatConfig.getFormat().
java.lang.String	format(java.lang.String format, java.lang.Object obj)	Converts the specified object to a number and returns a formatted string representing that number in the locale returned by LocaleConfig.getLocale().
java.lang.String	format(java.lang.String format, java.lang.Object obj, java.util.Locale locale)	Converts the specified object to a number and returns a formatted string representing that number in the specified Locale.
java.text.NumberFormat	getNumberFormat(java.lang.String format, java.util.Locale locale)	Returns a NumberFormat instance for the specified format and Locale.
java.lang.String	integer(java.lang.Object obj)	Convenience method equivalent to $number.format("integer", $foo).
java.lang.String	number(java.lang.Object obj)	Convenience method equivalent to $number.format("number", $foo).
java.lang.String	percent(java.lang.Object obj)	Convenience method equivalent to $number.format("percent", $foo).
java.lang.Boolean	toBoolean(java.lang.Object value)	Converts an object to an instance of Boolean if the object is not already an instance of Boolean.
java.lang.Number	toNumber(java.lang.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.
java.lang.Number	toNumber(java.lang.String format, java.lang.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.
java.lang.Number	toNumber(java.lang.String format, java.lang.Object obj, java.util.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.

Methods inherited from class org.apache.velocity.tools.generic.FormatConfig

configure, getFormat, setFormat

Methods inherited from class org.apache.velocity.tools.generic.LocaleConfig

getLocale, setLocale, toLocale

Methods inherited from class org.apache.velocity.tools.generic.SafeConfig

configure, getLog, initLogger, isConfigLocked, isSafeMode, setLockConfig, setSafeMode

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

NumberTool

public NumberTool()

Method Detail

format

public java.lang.String format(java.lang.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:

format(String format, Object obj, Locale locale)

currency

public java.lang.String currency(java.lang.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 java.lang.String integer(java.lang.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 java.lang.String number(java.lang.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 java.lang.String percent(java.lang.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 java.lang.String format(java.lang.String format,
                               java.lang.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(String format, Object obj, Locale locale)

format

public java.lang.String format(java.lang.String format,
                               java.lang.Object obj,
                               java.util.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 java.text.NumberFormat getNumberFormat(java.lang.String format,
                                              java.util.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:

NumberFormat

toNumber

public java.lang.Number toNumber(java.lang.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 java.lang.Number toNumber(java.lang.String format,
                                 java.lang.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(String format, Object obj, Locale locale)

toNumber

public java.lang.Number toNumber(java.lang.String format,
                                 java.lang.Object obj,
                                 java.util.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:

NumberFormat.parse(java.lang.String, java.text.ParsePosition)

toBoolean

public java.lang.Boolean toBoolean(java.lang.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