DateTimeConverter (Jakarta EE 8 Specification APIs)

java.lang.Object
- javax.faces.convert.DateTimeConverter

All Implemented Interfaces:

PartialStateHolder, StateHolder, Converter
```
public class DateTimeConverter
extends Object
implements Converter, PartialStateHolder
```
Converter implementation for java.util.Date values.

The getAsObject() method parses a String into a java.util.Date, according to the following algorithm:
- If the specified String is null, return a null. Otherwise, trim leading and trailing whitespace before proceeding.
- If the specified String - after trimming - has a zero length, return null.
- If the locale property is not null, use that Locale for managing parsing. Otherwise, use the Locale from the UIViewRoot.
- If a pattern has been specified, its syntax must conform the rules specified by java.text.SimpleDateFormat or java.time.format.DateTimeFormatter. Which of these two formatters is used depends on the value of type. Such a pattern will be used to parse, and the type, dateStyle, and timeStyle properties will be ignored, unless the value of type is one of the java.time specific values listed in setType(java.lang.String). In this case, DateTimeFormatter.ofPattern(String, Locale) must be called, passing the value of pattern as the first argument and the current Locale as the second argument, and this formatter must be used to parse the incoming value.
- If a pattern has not been specified, parsing will be based on the type property, which expects a date value, a time value, both, or one of several values specific to classes in java.time as listed in setType(java.lang.String). Any date and time values included will be parsed in accordance to the styles specified by dateStyle and timeStyle, respectively.
- If a timezone has been specified, it must be passed to the underlying DateFormat instance. Otherwise the "GMT" timezone is used.
- In all cases, parsing must be non-lenient; the given string must strictly adhere to the parsing format.
The getAsString() method expects a value of type java.util.Date (or a subclass), and creates a formatted String according to the following algorithm:
- If the specified value is null, return a zero-length String.
- If the specified value is a String, return it unmodified.
- If the locale property is not null, use that Locale for managing formatting. Otherwise, use the Locale from the UIViewRoot.
- If a timezone has been specified, it must be passed to the underlying DateFormat instance. Otherwise the "GMT" timezone is used.
- If a pattern has been specified, its syntax must conform the rules specified by java.text.SimpleDateFormat or java.time.format.DateTimeFormatter. Which of these two formatters is used depends on the value of type. Such a pattern will be used to format, and the type, dateStyle, and timeStyle properties will be ignored, unless the value of type is one of the java.time specific values listed in setType(java.lang.String). In this case, DateTimeFormatter.ofPattern(String, Locale) must be called, passing the value of pattern as the first argument and the current Locale as the second argument, and this formatter must be used to format the outgoing value.
- If a pattern has not been specified, formatting will be based on the type property, which includes a date value, a time value, both or into the formatted String. Any date and time values included will be formatted in accordance to the styles specified by dateStyle and timeStyle, respectively.

Field Summary

Fields
Modifier and Type	Field and Description
`static String`	`CONVERTER_ID` The standard converter id for this converter.
`static String`	`DATE_ID` The message identifier of the `FacesMessage` to be created if the conversion to `Date` fails.
`static String`	`DATETIME_ID` The message identifier of the `FacesMessage` to be created if the conversion to `DateTime` fails.
`static String`	`STRING_ID` The message identifier of the `FacesMessage` to be created if the conversion of the `DateTime` value to `String` fails.
`static String`	`TIME_ID` The message identifier of the `FacesMessage` to be created if the conversion to `Time` fails.

Fields inherited from interface javax.faces.convert.Converter
DATETIMECONVERTER_DEFAULT_TIMEZONE_IS_SYSTEM_TIMEZONE_PARAM_NAME

Constructor Summary

Constructors
Constructor and Description

DateTimeConverter()

Constructors
Constructor and Description
`DateTimeConverter()`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`clearInitialState()` Reset the PartialStateHolder to a non-delta tracking state.
`Object`	`getAsObject(FacesContext context, UIComponent component, String value)` Convert the specified string value, which is associated with the specified `UIComponent`, into a model data object that is appropriate for being stored during the Process Validations phase of the request processing lifecycle.
`String`	`getAsString(FacesContext context, UIComponent component, Object value)` Convert the specified model object value, which is associated with the specified `UIComponent`, into a String that is suitable for being included in the response generated during the Render Response phase of the request processing lifeycle.
`String`	`getDateStyle()` Return the style to be used to format or parse dates.
`Locale`	`getLocale()` Return the `Locale` to be used when parsing or formatting dates and times.
`String`	`getPattern()` Return the format pattern to be used when formatting and parsing dates and times.
`String`	`getTimeStyle()` Return the style to be used to format or parse times.
`TimeZone`	`getTimeZone()` Return the `TimeZone` used to interpret a time value.
`String`	`getType()` Return the type of value to be formatted or parsed.
`boolean`	`initialStateMarked()` Return `true` if delta state changes are being tracked, otherwise `false`
`boolean`	`isTransient()` If true, the Object implementing this interface must not participate in state saving or restoring.
`void`	`markInitialState()` The runtime must ensure that the `PartialStateHolder.markInitialState()` method is called on each instance of this interface in the view at the appropriate time to indicate the component is in its initial state.
`void`	`restoreState(FacesContext context, Object state)` Perform any processing required to restore the state from the entries in the state Object.
`Object`	`saveState(FacesContext context)` Gets the state of the instance as a `Serializable` Object.
`void`	`setDateStyle(String dateStyle)` Set the style to be used to format or parse dates.
`void`	`setLocale(Locale locale)` Set the `Locale` to be used when parsing or formatting dates and times.
`void`	`setPattern(String pattern)` Set the format pattern to be used when formatting and parsing dates and times.
`void`	`setTimeStyle(String timeStyle)` Set the style to be used to format or parse times.
`void`	`setTimeZone(TimeZone timeZone)` Set the `TimeZone` used to interpret a time value.
`void`	`setTransient(boolean transientFlag)` Denotes whether or not the Object implementing this interface must or must not participate in state saving or restoring.
`void`	`setType(String type)` Set the type of value to be formatted or parsed.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - CONVERTER_ID
```
public static final String CONVERTER_ID
```
    The standard converter id for this converter.
    
    See Also:
    
    Constant Field Values
  - DATE_ID
```
public static final String DATE_ID
```
    The message identifier of the FacesMessage to be created if the conversion to Date fails. The message format string for this message may optionally include the following placeholders:
    - {0} replaced by the unconverted value.
    - {1} replaced by an example value.
    - {2} replaced by a String whose value is the label of the input component that produced this message.
    See Also:
    
    Constant Field Values
  - TIME_ID
```
public static final String TIME_ID
```
    The message identifier of the FacesMessage to be created if the conversion to Time fails. The message format string for this message may optionally include the following placeholders:
    - {0} replaced by the unconverted value.
    - {1} replaced by an example value.
    - {2} replaced by a String whose value is the label of the input component that produced this message.
    See Also:
    
    Constant Field Values
  - DATETIME_ID
```
public static final String DATETIME_ID
```
    The message identifier of the FacesMessage to be created if the conversion to DateTime fails. The message format string for this message may optionally include the following placeholders:
    - {0} replaced by the unconverted value.
    - {1} replaced by an example value.
    - {2} replaced by a String whose value is the label of the input component that produced this message.
    See Also:
    
    Constant Field Values
  - STRING_ID
```
public static final String STRING_ID
```
    The message identifier of the FacesMessage to be created if the conversion of the DateTime value to String fails. The message format string for this message may optionally include the following placeholders:
    - {0} relaced by the unconverted value.
    - {1} replaced by a String whose value is the label of the input component that produced this message.
    See Also:
    
    Constant Field Values
- Constructor Detail
  - DateTimeConverter
```
public DateTimeConverter()
```
- Method Detail
  - getDateStyle
```
public String getDateStyle()
```
    Return the style to be used to format or parse dates. If not set, the default value, default, is returned.
    
    Returns:
    
    the style
  - setDateStyle
```
public void setDateStyle(String dateStyle)
```
    Set the style to be used to format or parse dates. Valid values are default, short, medium, long, and full. An invalid value will cause a ConverterException when getAsObject() or getAsString() is called.
    
    Parameters:
    
    dateStyle - The new style code
  - getLocale
```
public Locale getLocale()
```
    Return the Locale to be used when parsing or formatting dates and times. If not explicitly set, the Locale stored in the UIViewRoot for the current request is returned.
    
    Returns:
    
    the Locale
  - setLocale
```
public void setLocale(Locale locale)
```
    Set the Locale to be used when parsing or formatting dates and times. If set to null, the Locale stored in the UIViewRoot for the current request will be utilized.
    
    Parameters:
    
    locale - The new Locale (or null)
  - getPattern
```
public String getPattern()
```
    Return the format pattern to be used when formatting and parsing dates and times.
    
    Returns:
    
    the pattern
  - setPattern
```
public void setPattern(String pattern)
```
    Set the format pattern to be used when formatting and parsing dates and times. Valid values are those supported by java.text.SimpleDateFormat. An invalid value will cause a ConverterException when getAsObject() or getAsString() is called.
    
    Parameters:
    
    pattern - The new format pattern
  - getTimeStyle
```
public String getTimeStyle()
```
    Return the style to be used to format or parse times. If not set, the default value, default, is returned.
    
    Returns:
    
    the time style
  - setTimeStyle
```
public void setTimeStyle(String timeStyle)
```
    Set the style to be used to format or parse times. Valid values are default, short, medium, long, and full. An invalid value will cause a ConverterException when getAsObject() or getAsString() is called.
    
    Parameters:
    
    timeStyle - The new style code
  - getTimeZone
```
public TimeZone getTimeZone()
```
    Return the TimeZone used to interpret a time value. If not explicitly set, the default time zone of GMT returned.
    
    Returns:
    
    the TimeZone
  - setTimeZone
```
public void setTimeZone(TimeZone timeZone)
```
    Set the TimeZone used to interpret a time value.
    
    Parameters:
    
    timeZone - The new time zone
  - getType
```
public String getType()
```
    Return the type of value to be formatted or parsed. If not explicitly set, the default type, date is returned.
    
    Returns:
    
    the type
  - setType
```
public void setType(String type)
```
    Set the type of value to be formatted or parsed. Valid values are both, date, time localDate, localDateTime, localTime, offsetTime, offsetDateTime, or zonedDateTime. The values starting with "local", "offset" and "zoned" correspond to Java SE 8 Date Time API classes in package java.time with the name derived by upper casing the first letter. For example, java.time.LocalDate for the value "localDate". An invalid value will cause a ConverterException when getAsObject() or getAsString() is called.
    
    Parameters:
    
    type - The new date style
  - getAsObject
```
public Object getAsObject(FacesContext context,
                          UIComponent component,
                          String value)
```
    Description copied from interface: Converter
    
    Convert the specified string value, which is associated with the specified UIComponent, into a model data object that is appropriate for being stored during the Process Validations phase of the request processing lifecycle.
    
    Specified by:
    
    getAsObject in interface Converter
    
    Parameters:
    
    context - FacesContext for the request being processed
    
    component - UIComponent with which this model object value is associated
    
    value - String value to be converted (may be null)
    
    Returns:
    
    null if the value to convert is null, otherwise the result of the conversion
    
    Throws:
    
    ConverterException - if conversion cannot be successfully performed
    
    NullPointerException - if context or component is null
  - getAsString
```
public String getAsString(FacesContext context,
                          UIComponent component,
                          Object value)
```
    Description copied from interface: Converter
    
    Convert the specified model object value, which is associated with the specified UIComponent, into a String that is suitable for being included in the response generated during the Render Response phase of the request processing lifeycle.
    
    Specified by:
    
    getAsString in interface Converter
    
    Parameters:
    
    context - FacesContext for the request being processed
    
    component - UIComponent with which this model object value is associated
    
    value - Model object value to be converted (may be null)
    
    Returns:
    
    a zero-length String if value is null, otherwise the result of the conversion
    
    Throws:
    
    ConverterException - if conversion cannot be successfully performed
    
    NullPointerException - if context or component is null
  - saveState
```
public Object saveState(FacesContext context)
```
    Description copied from interface: StateHolder
    Gets the state of the instance as a Serializable Object.
    
    If the class that implements this interface has references to instances that implement StateHolder (such as a UIComponent with event handlers, validators, etc.) this method must call the StateHolder.saveState(javax.faces.context.FacesContext) method on all those instances as well. This method must not save the state of children and facets. That is done via the StateManager
    
    This method must not alter the state of the implementing object. In other words, after executing this code:
```
 Object state = component.saveState(facesContext);
 
```
    component should be the same as before executing it.
    
    The return from this method must be Serializable
    Specified by:
    
    saveState in interface StateHolder
    
    Parameters:
    
    context - the Faces context.
    
    Returns:
    
    the saved state.
  - restoreState
```
public void restoreState(FacesContext context,
                         Object state)
```
    Description copied from interface: StateHolder
    
    Perform any processing required to restore the state from the entries in the state Object.
    
    If the class that implements this interface has references to instances that also implement StateHolder (such as a UIComponent with event handlers, validators, etc.) this method must call the StateHolder.restoreState(javax.faces.context.FacesContext, java.lang.Object) method on all those instances as well.
    
    If the state argument is null, take no action and return.
    
    Specified by:
    
    restoreState in interface StateHolder
    
    Parameters:
    
    context - the Faces context.
    
    state - the state.
  - isTransient
```
public boolean isTransient()
```
    Description copied from interface: StateHolder
    
    If true, the Object implementing this interface must not participate in state saving or restoring.
    
    Specified by:
    
    isTransient in interface StateHolder
    
    Returns:
    
    true if transient, false otherwise.
  - setTransient
```
public void setTransient(boolean transientFlag)
```
    Description copied from interface: StateHolder
    
    Denotes whether or not the Object implementing this interface must or must not participate in state saving or restoring.
    
    Specified by:
    
    setTransient in interface StateHolder
    
    Parameters:
    
    transientFlag - boolean pass true if this Object will not participate in state saving or restoring, otherwise pass false.
  - markInitialState
```
public void markInitialState()
```
    Description copied from interface: PartialStateHolder
    
    The runtime must ensure that the PartialStateHolder.markInitialState() method is called on each instance of this interface in the view at the appropriate time to indicate the component is in its initial state. The implementor of the interface must ensure that PartialStateHolder.initialStateMarked() returns true from the time markInitialState() is called until PartialStateHolder.clearInitialState() is called, after which time initialStateMarked() must return false. Also, during the time that the instance returns true from initialStateMarked(), the implementation must return only the state that has changed in its implementation of StateHolder.saveState(javax.faces.context.FacesContext).
    
    Specified by:
    
    markInitialState in interface PartialStateHolder
  - initialStateMarked
```
public boolean initialStateMarked()
```
    Description copied from interface: PartialStateHolder
    
    Return true if delta state changes are being tracked, otherwise false
    
    Specified by:
    
    initialStateMarked in interface PartialStateHolder
    
    Returns:
    
    true if the initial state is marked, false otherwise.
  - clearInitialState
```
public void clearInitialState()
```
    Description copied from interface: PartialStateHolder
    
    Reset the PartialStateHolder to a non-delta tracking state.
    
    Specified by:
    
    clearInitialState in interface PartialStateHolder

Class DateTimeConverter

Field Summary

Fields inherited from interface javax.faces.convert.Converter

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

CONVERTER_ID

DATE_ID

TIME_ID

DATETIME_ID

STRING_ID

Constructor Detail

DateTimeConverter

Method Detail

getDateStyle

setDateStyle

getLocale

setLocale

getPattern

setPattern

getTimeStyle

setTimeStyle

getTimeZone

setTimeZone

getType

setType

getAsObject

getAsString

saveState

restoreState

isTransient

setTransient

markInitialState

initialStateMarked

clearInitialState