JSTL - fmt를 사용해서 데이터 format 변경하기.

jstl의 fmt를 사용하면 날자 데이터를 사용자가 원하는 표기법으로 표기한다던지(yyyy-mm-dd) 숫자 형식에서 소수점을 몇째짜리 까지 표현할 것인지를 정의 할 수 있다.

작업 순서
1. jsp 상단에 fmt 를 선언해 준다.
<%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt" %>

2. 원하는 위치에 <fmt:~~ 이용해서 포맷을 변경한다.


다양한 fmt의 Attribute

1. fmt:formatNumber Attributes
Name	Required	Request-time	Type	Description
value	false	true	java.lang.String	Numeric value to be formatted.
type	false	true	java.lang.String	Specifies whether the value is to be formatted as number, currency, or percentage.
pattern	false	true	java.lang.String	Custom formatting pattern.
currencyCode	false	true	java.lang.String	ISO 4217 currency code. Applied only when formatting currencies (i.e. if type is equal to "currency"); ignored otherwise.
currencySymbol	false	true	java.lang.String	Currency symbol. Applied only when formatting currencies (i.e. if type is equal to "currency"); ignored otherwise.
groupingUsed	false	true	java.lang.String	Specifies whether the formatted output will contain any grouping separators.
maxIntegerDigits	false	true	java.lang.String	Maximum number of digits in the integer portion of the formatted output.
minIntegerDigits	false	true	java.lang.String	Minimum number of digits in the integer portion of the formatted output.
maxFractionDigits	false	true	java.lang.String	Maximum number of digits in the fractional portion of the formatted output.
minFractionDigits	false	true	java.lang.String	Minimum number of digits in the fractional portion of the formatted output.
var	false	false	java.lang.String	Name of the exported scoped variable which stores the formatted result as a String.
scope	false	false	java.lang.String	Scope of var.

 

2. fmt:parseNumber Attributes
Name	Required	Request-time	Type	Description
value	false	true	java.lang.String	String to be parsed.
type	false	true	java.lang.String	Specifies whether the string in the value attribute should be parsed as a number, currency, or percentage.
pattern	false	true	java.lang.String	Custom formatting pattern that determines how the string in the value attribute is to be parsed.
parseLocale	false	true	java.lang.String	Locale whose default formatting pattern (for numbers, currencies, or percentages, respectively) is to be used during the parse operation, or to which the pattern specified via the pattern attribute (if present) is applied.
integerOnly	false	true	java.lang.String	Specifies whether just the integer portion of the given value should be parsed.
var	false	false	java.lang.String	Name of the exported scoped variable which stores the parsed result (of type java.lang.Number).
scope	false	false	java.lang.String	Scope of var.

 

ex) 패턴 예제

  <fmt:formatNumber value="123456.78" pattern=",###"/> 3자리 기준으로 "," 찍기 (금액 / 소수점 제거)

  <fmt:formatNumber value="123456.78" pattern=".##"/> #의 갯수에 따라 소수점을 출력함 (반올림)

 

3. fmt:formatDate Attributes
Name	Required	Request-time	Type	Description
value	true	true	java.lang.String	Date and/or time to be formatted.
type	false	true	java.lang.String	Specifies whether the time, the date, or both the time and date components of the given date are to be formatted.
dateStyle	false	true	java.lang.String	Predefined formatting style for dates. Follows the semantics defined in class java.text.DateFormat. Applied only when formatting a date or both a date and time (i.e. if type is missing or is equal to "date" or "both"); ignored otherwise.
timeStyle	false	true	java.lang.String	Predefined formatting style for times. Follows the semantics defined in class java.text.DateFormat. Applied only when formatting a time or both a date and time (i.e. if type is equal to "time" or "both"); ignored otherwise.
pattern	false	true	java.lang.String	Custom formatting style for dates and times.
timeZone	false	true	java.lang.String	Time zone in which to represent the formatted time.
var	false	false	java.lang.String	Name of the exported scoped variable which stores the formatted result as a String.
scope	false	false	java.lang.String	Scope of var.

 

4. fmt:parseDate Attributes
Name	Required	Request-time	Type	Description
value	false	true	java.lang.String	Date string to be parsed.
type	false	true	java.lang.String	Specifies whether the date string in the value attribute is supposed to contain a time, a date, or both.
dateStyle	false	true	java.lang.String	Predefined formatting style for days which determines how the date component of the date string is to be parsed. Applied only when formatting a date or both a date and time (i.e. if type is missing or is equal to "date" or "both"); ignored otherwise.
timeStyle	false	true	java.lang.String	Predefined formatting styles for times which determines how the time component in the date string is to be parsed. Applied only when formatting a time or both a date and time (i.e. if type is equal to "time" or "both"); ignored otherwise.
pattern	false	true	java.lang.String	Custom formatting pattern which determines how the date string is to be parsed.
timeZone	false	true	java.lang.String	Time zone in which to interpret any time information in the date string.
parseLocale	false	true	java.lang.String	Locale whose predefined formatting styles for dates and times are to be used during the parse operation, or to which the pattern specified via the pattern attribute (if present) is applied.
var	false	false	java.lang.String	Name of the exported scoped variable in which the parsing result (of type java.util.Date) is stored.
scope	false	false	java.lang.String	Scope of var.

 

ex) 표기법 예제

  <fmt:formatDate value="timstamp" type="both" pattern="yy-MM-dd hh:mm"/> 날짜 및 시간

  <fmt:formatDate value="timstamp" type="date" pattern="yy-MM-dd"/> 날짜

  <fmt:formatDate value="timstamp" type="time" pattern="hh:mm"/> 시간

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