com.fitbur.jackson.annotation.JsonFormat Maven / Gradle / Ivy
package com.fitbur.jackson.annotation;
import java.lang.annotation.*;
import java.util.Locale;
import java.util.TimeZone;
/**
* General-purpose annotation used for configuring details of how
* values of properties are to be serialized.
* Unlike most other Jackson annotations, annotation does not
* have specific universal interpretation: instead, effect depends on datatype
* of property being annotated (or more specifically, deserializer
* and serializer being used).
*
* Common uses include choosing between alternate representations -- for example,
* whether {@link java.util.Date} is to be serialized as number (Java timestamp)
* or String (such as ISO-8601 compatible time value) -- as well as configuring
* exact details with {@link #pattern} property.
*
* As of Jackson 2.6, known special handling includes:
*
* - {@link java.util.Date}: Shape can be {@link Shape#STRING} or {@link Shape#NUMBER};
* pattern may contain {@link java.text.SimpleDateFormat}-compatible pattern definition.
*
* - Can be used on Classes (types) as well, for modified default behavior, possibly
* overridden by per-property annotation
*
* - {@link java.lang.Enum}s: Shapes {@link Shape#STRING} and {@link Shape#NUMBER} can be
* used to change between numeric (index) and textual (name or
toString());
* but it is also possible to use {@link Shape#OBJECT} to serialize (but not deserialize)
* {@link java.lang.Enum}s as JSON Objects (as if they were POJOs). NOTE: serialization
* as JSON Object only works with class annotation;
* will not work as per-property annotation.
*
* - {@link java.util.Collection}s can be serialized as (and deserialized from) JSON Objects,
* if {@link Shape#OBJECT} is used. NOTE: can ONLY be used as class annotation;
* will not work as per-property annotation.
*
* - {@link java.lang.Number} subclasses can be serialized as full objects if
* {@link Shape#OBJECT} is used. Otherwise the default behavior of serializing to a
* scalar number value will be preferred. NOTE: can ONLY be used as class annotation;
* will not work as per-property annotation.
*
*
*
* @since 2.0
*/
@Target({ElementType.ANNOTATION_TYPE, ElementType.FIELD, ElementType.METHOD, ElementType.PARAMETER,
ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@JacksonAnnotation
public @interface JsonFormat
{
/**
* Value that indicates that default {@link java.util.Locale}
* (from deserialization or serialization context) should be used:
* annotation does not define value to use.
*/
public final static String DEFAULT_LOCALE = "##default";
/**
* Value that indicates that default {@link java.util.TimeZone}
* (from deserialization or serialization context) should be used:
* annotation does not define value to use.
*/
public final static String DEFAULT_TIMEZONE = "##default";
/**
* Datatype-specific additional piece of configuration that may be used
* to further refine formatting aspects. This may, for example, determine
* low-level format String used for {@link java.util.Date} serialization;
* however, exact use is determined by specific JsonSerializer
*/
public String pattern() default "";
/**
* Structure to use for serialization: definition of mapping depends on datatype,
* but usually has straight-forward counterpart in data format (JSON).
* Note that commonly only a subset of shapes is available; and if 'invalid' value
* is chosen, defaults are usually used.
*/
public Shape shape() default Shape.ANY;
/**
* {@link java.util.Locale} to use for serialization (if needed).
* Special value of {@link #DEFAULT_LOCALE}
* can be used to mean "just use the default", where default is specified
* by the serialization context, which in turn defaults to system
* defaults ({@link java.util.Locale#getDefault()}) unless explicitly
* set to another locale.
*/
public String locale() default DEFAULT_LOCALE;
/**
* {@link java.util.TimeZone} to use for serialization (if needed).
* Special value of {@link #DEFAULT_TIMEZONE}
* can be used to mean "just use the default", where default is specified
* by the serialization context, which in turn defaults to system
* defaults ({@link java.util.TimeZone#getDefault()}) unless explicitly
* set to another locale.
*/
public String timezone() default DEFAULT_TIMEZONE;
/**
* Set of {@link JsonFormat.Feature}s to explicitly enable with respect
* to handling of annotated property. This will have precedence over possible
* global configuration.
*
* @since 2.6
*/
public JsonFormat.Feature[] with() default { };
/**
* Set of {@link JsonFormat.Feature}s to explicitly disable with respect
* to handling of annotated property. This will have precedence over possible
* global configuration.
*
* @since 2.6
*/
public JsonFormat.Feature[] without() default { };
/*
/**********************************************************
/* Value enumeration(s), value class(es)
/**********************************************************
*/
/**
* Value enumeration used for indicating preferred Shape; translates
* loosely to JSON types, with some extra values to indicate less precise
* choices (i.e. allowing one of multiple actual shapes)
*/
public enum Shape
{
/**
* Marker enum value that indicates "default" (or "whatever") choice; needed
* since Annotations can not have null values for enums.
*/
ANY,
/**
* Value that indicates shape should not be structural (that is, not
* {@link #ARRAY} or {@link #OBJECT}, but can be any other shape.
*/
SCALAR,
/**
* Value that indicates that (JSON) Array type should be used.
*/
ARRAY,
/**
* Value that indicates that (JSON) Object type should be used.
*/
OBJECT,
/**
* Value that indicates that a numeric (JSON) type should be used
* (but does not specify whether integer or floating-point representation
* should be used)
*/
NUMBER,
/**
* Value that indicates that floating-point numeric type should be used
*/
NUMBER_FLOAT,
/**
* Value that indicates that integer number type should be used
* (and not {@link #NUMBER_FLOAT}).
*/
NUMBER_INT,
/**
* Value that indicates that (JSON) String type should be used.
*/
STRING,
/**
* Value that indicates that (JSON) boolean type
* (true, false) should be used.
*/
BOOLEAN
;
public boolean isNumeric() {
return (this == NUMBER) || (this == NUMBER_INT) || (this == NUMBER_FLOAT);
}
public boolean isStructured() {
return (this == OBJECT) || (this == ARRAY);
}
}
/**
* Set of features that can be enabled/disabled for property annotated.
* These often relate to specific SerializationFeature
* or DeserializationFeature, as noted by entries.
*
* Note that whether specific setting has an effect depends on whether
* JsonSerializer / JsonDeserializer being used
* takes the format setting into account. If not, please file an issue
* for adding support via issue tracker for package that has handlers
* (if you know which one; if not, just use `jackson-databind`).
*
* @since 2.6
*/
public enum Feature {
/**
* Override for DeserializationFeature.ACCEPT_SINGLE_VALUE_AS_ARRAY
* which will allow deserialization of JSON non-array values into single-element
* Java arrays and {@link java.util.Collection}s.
*/
ACCEPT_SINGLE_VALUE_AS_ARRAY,
/**
* Override for SerializationFeature.WRITE_DATE_TIMESTAMPS_AS_NANOSECONDS,
* similar constraints apply.
*/
WRITE_DATE_TIMESTAMPS_AS_NANOSECONDS,
/**
* Override for SerializationFeature.WRITE_DATES_WITH_ZONE_ID,
* similar constraints apply.
*/
WRITE_DATES_WITH_ZONE_ID,
/**
* Override for SerializationFeature.WRITE_SINGLE_ELEM_ARRAYS_UNWRAPPED
* which will force serialization of single-element arrays and {@link java.util.Collection}s
* as that single element and excluding array wrapper.
*/
WRITE_SINGLE_ELEM_ARRAYS_UNWRAPPED,
/**
* Override for SerializationFeature.ORDER_MAP_ENTRIES_BY_KEYS,
* enabling of which will force sorting of {@link java.util.Map} keys before
* serialization.
*/
WRITE_SORTED_MAP_ENTRIES,
;
}
/**
* Helper class that encapsulates information equivalent to {@link java.lang.Boolean}
* valued {@link java.util.EnumMap}.
*
* @since 2.6
*/
public static class Features
{
private final int _enabled, _disabled;
private final static Features EMPTY = new Features(0, 0);
private Features(int e, int d) {
_enabled = e;
_disabled = d;
}
public static Features empty() {
return EMPTY;
}
public static Features construct(JsonFormat f) {
return construct(f.with(), f.without());
}
public static Features construct(Feature[] enabled, Feature[] disabled)
{
int e = 0;
for (Feature f : enabled) {
e |= (1 << f.ordinal());
}
int d = 0;
for (Feature f : disabled) {
d |= (1 << f.ordinal());
}
return new Features(e, d);
}
public Features withOverrides(Features overrides) {
// Cheap checks first: maybe one is empty?
if (overrides == null) {
return this;
}
int overrideD = overrides._disabled;
int overrideE = overrides._enabled;
if ((overrideD == 0) && (overrideE == 0)) {
return this;
}
if ((_enabled == 0) && (_disabled == 0)) {
return overrides;
}
// If not, calculate combination with overrides
int newE = (_enabled & ~overrideD) | overrideE;
int newD = (_disabled & ~overrideE) | overrideD;
// one more thing; no point in creating new instance if there's no change
if ((newE == _enabled) && (newD == _disabled)) {
return this;
}
return new Features(newE, newD);
}
public Features with(Feature...features) {
int e = _enabled;
for (Feature f : features) {
e |= (1 << f.ordinal());
}
return (e == _enabled) ? this : new Features(e, _disabled);
}
public Features without(Feature...features) {
int d = _disabled;
for (Feature f : features) {
d |= (1 << f.ordinal());
}
return (d == _disabled) ? this : new Features(_enabled, d);
}
public Boolean get(Feature f) {
int mask = (1 << f.ordinal());
if ((_disabled & mask) != 0) {
return Boolean.FALSE;
}
if ((_enabled & mask) != 0) {
return Boolean.TRUE;
}
return null;
}
@Override
public int hashCode() {
return _disabled + _enabled;
}
@Override
public boolean equals(Object o) {
if (o == this) return true;
if (o == null) return false;
if (o.getClass() != getClass()) return false;
Features other = (Features) o;
return (other._enabled == _enabled) && (other._disabled == _disabled);
}
}
/**
* Helper class used to contain information from a single {@link JsonFormat}
* annotation.
*/
public static class Value
implements JacksonAnnotationValue, // since 2.6
java.io.Serializable
{
private static final long serialVersionUID = 1L;
private final static Value EMPTY = new Value();
private final String _pattern;
private final Shape _shape;
private final Locale _locale;
private final String _timezoneStr;
/**
* @since 2.6
*/
private final Features _features;
// lazily constructed when created from annotations
private transient TimeZone _timezone;
public Value() {
this("", Shape.ANY, "", "", Features.empty());
}
public Value(JsonFormat ann) {
this(ann.pattern(), ann.shape(), ann.locale(), ann.timezone(),
Features.construct(ann));
}
/**
* @since 2.6
*/
public Value(String p, Shape sh, String localeStr, String tzStr, Features f)
{
this(p, sh,
(localeStr == null || localeStr.length() == 0 || DEFAULT_LOCALE.equals(localeStr)) ?
null : new Locale(localeStr),
(tzStr == null || tzStr.length() == 0 || DEFAULT_TIMEZONE.equals(tzStr)) ?
null : tzStr,
null, f);
}
/**
* @since 2.6
*/
public Value(String p, Shape sh, Locale l, TimeZone tz, Features f)
{
_pattern = p;
_shape = (sh == null) ? Shape.ANY : sh;
_locale = l;
_timezone = tz;
_timezoneStr = null;
_features = (f == null) ? Features.empty() : f;
}
/**
* @since 2.6
*/
public Value(String p, Shape sh, Locale l, String tzStr, TimeZone tz, Features f)
{
_pattern = p;
_shape = (sh == null) ? Shape.ANY : sh;
_locale = l;
_timezone = tz;
_timezoneStr = tzStr;
_features = (f == null) ? Features.empty() : f;
}
/**
* @deprecated since 2.6
*/
@Deprecated
public Value(String p, Shape sh, Locale l, TimeZone tz) {
this(p, sh, l, tz, Features.empty());
}
/**
* @deprecated since 2.6
*/
@Deprecated
public Value(String p, Shape sh, String localeStr, String tzStr) {
this(p, sh, localeStr, tzStr, Features.empty());
}
/**
* @deprecated since 2.6
*/
@Deprecated
public Value(String p, Shape sh, Locale l, String tzStr, TimeZone tz) {
this(p, sh, l, tzStr, tz, Features.empty());
}
/**
* @since 2.7
*/
public final static Value empty() {
return EMPTY;
}
/**
* @since 2.7
*/
public final static Value from(JsonFormat ann) {
if (ann == null) { // os EMPTY?
return null;
}
return new Value(ann);
}
/**
* @since 2.7
*/
public final Value withOverrides(Value overrides) {
if ((overrides == null) || (overrides == EMPTY)) {
return this;
}
if (this == EMPTY) { // cheesy, but probably common enough
return overrides;
}
String p = overrides._pattern;
if ((p == null) || p.isEmpty()) {
p = _pattern;
}
Shape sh = overrides._shape;
if (sh == Shape.ANY) {
sh = _shape;
}
Locale l = overrides._locale;
if (l == null) {
l = _locale;
}
Features f = _features;
if (f == null) {
f = overrides._features;
} else {
f = f.withOverrides(overrides._features);
}
// timezone not merged, just choose one
String tzStr = overrides._timezoneStr;
TimeZone tz;
if ((tzStr == null) || tzStr.isEmpty()) { // no overrides, use space
tzStr = _timezoneStr;
tz = _timezone;
} else {
tz = overrides._timezone;
}
return new Value(p, sh, l, tzStr, tz, f);
}
/**
* @since 2.6
*/
public static Value forPattern(String p) {
return new Value(p, null, null, null, null, Features.empty());
}
/**
* @since 2.7
*/
public static Value forShape(Shape sh) {
return new Value(null, sh, null, null, null, Features.empty());
}
/**
* @since 2.1
*/
public Value withPattern(String p) {
return new Value(p, _shape, _locale, _timezoneStr, _timezone, _features);
}
/**
* @since 2.1
*/
public Value withShape(Shape s) {
return new Value(_pattern, s, _locale, _timezoneStr, _timezone, _features);
}
/**
* @since 2.1
*/
public Value withLocale(Locale l) {
return new Value(_pattern, _shape, l, _timezoneStr, _timezone, _features);
}
/**
* @since 2.1
*/
public Value withTimeZone(TimeZone tz) {
return new Value(_pattern, _shape, _locale, null, tz, _features);
}
/**
* @since 2.6
*/
public Value withFeature(JsonFormat.Feature f) {
Features newFeats = _features.with(f);
return (newFeats == _features) ? this :
new Value(_pattern, _shape, _locale, _timezoneStr, _timezone, newFeats);
}
/**
* @since 2.6
*/
public Value withoutFeature(JsonFormat.Feature f) {
Features newFeats = _features.without(f);
return (newFeats == _features) ? this :
new Value(_pattern, _shape, _locale, _timezoneStr, _timezone, newFeats);
}
@Override
public Class valueFor() {
return JsonFormat.class;
}
public String getPattern() { return _pattern; }
public Shape getShape() { return _shape; }
public Locale getLocale() { return _locale; }
/**
* Alternate access (compared to {@link #getTimeZone()}) which is useful
* when caller just wants time zone id to convert, but not as JDK
* provided {@link TimeZone}
*
* @since 2.4
*/
public String timeZoneAsString() {
if (_timezone != null) {
return _timezone.getID();
}
return _timezoneStr;
}
public TimeZone getTimeZone() {
TimeZone tz = _timezone;
if (tz == null) {
if (_timezoneStr == null) {
return null;
}
tz = TimeZone.getTimeZone(_timezoneStr);
_timezone = tz;
}
return tz;
}
/**
* @since 2.4
*/
public boolean hasShape() { return _shape != Shape.ANY; }
/**
* @since 2.4
*/
public boolean hasPattern() {
return (_pattern != null) && (_pattern.length() > 0);
}
/**
* @since 2.4
*/
public boolean hasLocale() { return _locale != null; }
/**
* @since 2.4
*/
public boolean hasTimeZone() {
return (_timezone != null) || (_timezoneStr != null && !_timezoneStr.isEmpty());
}
/**
* Accessor for checking whether this format value has specific setting for
* given feature. Result is 3-valued with either `null`, {@link Boolean#TRUE} or
* {@link Boolean#FALSE}, indicating 'yes/no/dunno' choices, where `null` ("dunno")
* indicates that the default handling should be used based on global defaults,
* and there is no format override.
*
* @since 2.6
*/
public Boolean getFeature(JsonFormat.Feature f) {
return _features.get(f);
}
@Override
public String toString() {
return String.format("[pattern=%s,shape=%s,locale=%s,timezone=%s]",
_pattern, _shape, _locale, _timezoneStr);
}
@Override
public int hashCode() {
int hash = (_timezoneStr == null) ? 1 : _timezoneStr.hashCode();
if (_pattern != null) {
hash ^= _pattern.hashCode();
}
hash += _shape.hashCode();
if (_locale != null) {
hash ^= _locale.hashCode();
}
hash += _features.hashCode();
return hash;
}
@Override
public boolean equals(Object o) {
if (o == this) return true;
if (o == null) return false;
if (o.getClass() != getClass()) return false;
Value other = (Value) o;
if ((_shape != other._shape)
|| !_features.equals(other._features)) {
return false;
}
return _equal(_timezoneStr, other._timezoneStr)
&& _equal(_pattern, other._pattern)
&& _equal(_timezone, other._timezone)
&& _equal(_locale, other._locale);
}
private static boolean _equal(T value1, T value2)
{
if (value1 == null) {
return (value2 == null);
} else if (value2 == null) {
return false;
}
return value1.equals(value2);
}
}
}