| package com.fasterxml.jackson.databind; |
| |
| import com.fasterxml.jackson.databind.cfg.ConfigFeature; |
| |
| /** |
| * Enumeration that defines simple on/off features that affect |
| * the way Java objects are serialized. |
| *<p> |
| * Note that features can be set both through |
| * {@link ObjectMapper} (as sort of defaults) and through |
| * {@link ObjectWriter}. |
| * In first case these defaults must follow "config-then-use" patterns |
| * (i.e. defined once, not changed afterwards); all per-call |
| * changes must be done using {@link ObjectWriter}. |
| */ |
| public enum SerializationFeature implements ConfigFeature |
| { |
| /* |
| /****************************************************** |
| /* Generic output features |
| /****************************************************** |
| */ |
| |
| /** |
| * Feature that can be enabled to make root value (usually JSON |
| * Object but can be any type) wrapped within a single property |
| * JSON object, where key as the "root name", as determined by |
| * annotation introspector (esp. for JAXB that uses |
| * <code>@XmlRootElement.name</code>) or fallback (non-qualified |
| * class name). |
| * Feature is mostly intended for JAXB compatibility. |
| *<p> |
| * Feature is disabled by default. |
| */ |
| WRAP_ROOT_VALUE(false), |
| |
| /** |
| * Feature that allows enabling (or disabling) indentation |
| * for the underlying generator, using the default pretty |
| * printer (see |
| * {@link com.fasterxml.jackson.core.JsonGenerator#useDefaultPrettyPrinter} |
| * for details). |
| *<p> |
| * Note that this only affects cases where |
| * {@link com.fasterxml.jackson.core.JsonGenerator} |
| * is constructed implicitly by ObjectMapper: if explicit |
| * generator is passed, its configuration is not changed. |
| *<p> |
| * Also note that if you want to configure details of indentation, |
| * you need to directly configure the generator: there is a |
| * method to use any <code>PrettyPrinter</code> instance. |
| * This feature will only allow using the default implementation. |
| *<p> |
| * Feature is enabled by default. |
| */ |
| INDENT_OUTPUT(false), |
| |
| /* |
| /****************************************************** |
| /* Error handling features |
| /****************************************************** |
| */ |
| |
| /** |
| * Feature that determines what happens when no accessors are |
| * found for a type (and there are no annotations to indicate |
| * it is meant to be serialized). If enabled (default), an |
| * exception is thrown to indicate these as non-serializable |
| * types; if disabled, they are serialized as empty Objects, |
| * i.e. without any properties. |
| *<p> |
| * Note that empty types that this feature has only effect on |
| * those "empty" beans that do not have any recognized annotations |
| * (like <code>@JsonSerialize</code>): ones that do have annotations |
| * do not result in an exception being thrown. |
| *<p> |
| * Feature is enabled by default. |
| */ |
| FAIL_ON_EMPTY_BEANS(true), |
| |
| /** |
| * Feature that determines whether Jackson code should catch |
| * and wrap {@link Exception}s (but never {@link Error}s!) |
| * to add additional information about |
| * location (within input) of problem or not. If enabled, |
| * most exceptions will be caught and re-thrown (exception |
| * specifically being that {@link java.io.IOException}s may be passed |
| * as is, since they are declared as throwable); this can be |
| * convenient both in that all exceptions will be checked and |
| * declared, and so there is more contextual information. |
| * However, sometimes calling application may just want "raw" |
| * unchecked exceptions passed as is. |
| *<p> |
| *<p> |
| * Feature is enabled by default. |
| */ |
| WRAP_EXCEPTIONS(true), |
| |
| /* |
| /****************************************************** |
| /* Output life cycle features |
| /****************************************************** |
| */ |
| |
| /** |
| * Feature that determines whether <code>close</code> method of |
| * serialized <b>root level</b> objects (ones for which <code>ObjectMapper</code>'s |
| * writeValue() (or equivalent) method is called) |
| * that implement {@link java.io.Closeable} |
| * is called after serialization or not. If enabled, <b>close()</b> will |
| * be called after serialization completes (whether succesfully, or |
| * due to an error manifested by an exception being thrown). You can |
| * think of this as sort of "finally" processing. |
| *<p> |
| * NOTE: only affects behavior with <b>root</b> objects, and not other |
| * objects reachable from the root object. Put another way, only one |
| * call will be made for each 'writeValue' call. |
| *<p> |
| * Feature is disabled by default. |
| */ |
| CLOSE_CLOSEABLE(false), |
| |
| /** |
| * Feature that determines whether <code>JsonGenerator.flush()</code> is |
| * called after <code>writeValue()</code> method <b>that takes JsonGenerator |
| * as an argument</b> completes (i.e. does NOT affect methods |
| * that use other destinations); same for methods in {@link ObjectWriter}. |
| * This usually makes sense; but there are cases where flushing |
| * should not be forced: for example when underlying stream is |
| * compressing and flush() causes compression state to be flushed |
| * (which occurs with some compression codecs). |
| *<p> |
| * Feature is enabled by default. |
| */ |
| FLUSH_AFTER_WRITE_VALUE(true), |
| |
| /* |
| /****************************************************** |
| /* Datatype-specific serialization configuration |
| /****************************************************** |
| */ |
| |
| /** |
| * Feature that determines whether {@link java.util.Date} values |
| * (and Date-based things like {@link java.util.Calendar}s) are to be |
| * serialized as numeric timestamps (true; the default), |
| * or as something else (usually textual representation). |
| * If textual representation is used, the actual format is |
| * one returned by a call to |
| * {@link com.fasterxml.jackson.databind.SerializationConfig#getDateFormat}. |
| *<p> |
| * Note: whether this feature affects handling of other date-related |
| * types depend on handlers of those types, although ideally they |
| * should use this feature |
| *<p> |
| * Note: whether {@link java.util.Map} keys are serialized as Strings |
| * or not is controlled using {@link #WRITE_DATE_KEYS_AS_TIMESTAMPS}. |
| *<p> |
| * Feature is enabled by default. |
| */ |
| WRITE_DATES_AS_TIMESTAMPS(true), |
| |
| /** |
| * Feature that determines whether {@link java.util.Date}s |
| * (and sub-types) used as {@link java.util.Map} keys are serialized |
| * as timestamps or not (if not, will be serialized as textual |
| * values). |
| *<p> |
| * Default value is 'false', meaning that Date-valued Map keys are serialized |
| * as textual (ISO-8601) values. |
| *<p> |
| * Feature is disabled by default. |
| */ |
| WRITE_DATE_KEYS_AS_TIMESTAMPS(false), |
| |
| /** |
| * Feature that determines how type <code>char[]</code> is serialized: |
| * when enabled, will be serialized as an explict JSON array (with |
| * single-character Strings as values); when disabled, defaults to |
| * serializing them as Strings (which is more compact). |
| *<p> |
| * Feature is disabled by default. |
| */ |
| WRITE_CHAR_ARRAYS_AS_JSON_ARRAYS(false), |
| |
| /** |
| * Feature that determines standard serialization mechanism used for |
| * Enum values: if enabled, return value of <code>Enum.toString()</code> |
| * is used; if disabled, return value of <code>Enum.name()</code> is used. |
| *<p> |
| * Note: this feature should usually have same value |
| * as {@link DeserializationFeature#READ_ENUMS_USING_TO_STRING}. |
| *<p> |
| * Feature is disabled by default. |
| */ |
| WRITE_ENUMS_USING_TO_STRING(false), |
| |
| /** |
| * Feature that determines whethere Java Enum values are serialized |
| * as numbers (true), or textual values (false). If textual values are |
| * used, other settings are also considered. |
| * If this feature is enabled, |
| * return value of <code>Enum.ordinal()</code> |
| * (an integer) will be used as the serialization. |
| *<p> |
| * Note that this feature has precedence over {@link #WRITE_ENUMS_USING_TO_STRING}, |
| * which is only considered if this feature is set to false. |
| *<p> |
| * Feature is disabled by default. |
| */ |
| WRITE_ENUMS_USING_INDEX(false), |
| |
| /** |
| * Feature that determines whether Map entries with null values are |
| * to be serialized (true) or not (false). |
| *<p> |
| * For further details, check out [JACKSON-314] |
| *<p> |
| * Feature is enabled by default. |
| */ |
| WRITE_NULL_MAP_VALUES(true), |
| |
| /** |
| * Feature that determines whether Container properties (POJO properties |
| * with declared value of Collection or array; i.e. things that produce JSON |
| * arrays) that are empty (have no elements) |
| * will be serialized as empty JSON arrays (true), or suppressed from output (false). |
| *<p> |
| * Note that this does not change behavior of {@link java.util.Map}s, or |
| * "Collection-like" types. |
| *<p> |
| * Feature is enabled by default. |
| */ |
| WRITE_EMPTY_JSON_ARRAYS(true), |
| |
| /** |
| * Feature added for interoperability, to work with oddities of |
| * so-called "BadgerFish" convention. |
| * Feature determines handling of single element {@link java.util.Collection}s |
| * and arrays: if enabled, {@link java.util.Collection}s and arrays that contain exactly |
| * one element will be serialized as if that element itself was serialized. |
| *<p> |
| * When enabled, a POJO with array that normally looks like this: |
| *<pre> |
| * { "arrayProperty" : [ 1 ] } |
| *</pre> |
| * will instead be serialized as |
| *<pre> |
| * { "arrayProperty" : 1 } |
| *</pre> |
| *<p> |
| * Note that this feature is counterpart to {@link DeserializationFeature#ACCEPT_SINGLE_VALUE_AS_ARRAY} |
| * (that is, usually both are enabled, or neither is). |
| *<p> |
| * Feature is disabled by default, so that no special handling is done. |
| */ |
| WRITE_SINGLE_ELEM_ARRAYS_UNWRAPPED(false), |
| |
| /** |
| * Feature that determines whether {@link java.math.BigDecimal} entries are |
| * serialized using {@link java.math.BigDecimal#toPlainString()} to prevent |
| * values to be written using scientific notation. |
| * <p> |
| * Feature is disabled by default. |
| */ |
| WRITE_BIGDECIMAL_AS_PLAIN(false), |
| |
| /** |
| * Feature that controls whether numeric timestamp values are |
| * to be written using nanosecond timestamps (enabled) or not (disabled); |
| * <b>if and only if</b> datatype supports such resolution. |
| * Only newer datatypes (such as Java8 Date/Time) support such resolution -- |
| * older types (pre-Java8 <b>java.util.Date</b> etc) and Joda do not -- |
| * and this setting <b>has no effect</b> on such types. |
| *<p> |
| * If disabled, standard millisecond timestamps are assumed. |
| * This is the counterpart to {@link SerializationFeature#WRITE_DATE_TIMESTAMPS_AS_NANOSECONDS}. |
| *<p> |
| * Feature is enabled by default, to support most accurate time values possible. |
| * |
| * @since 2.2 |
| */ |
| WRITE_DATE_TIMESTAMPS_AS_NANOSECONDS(true), |
| |
| /** |
| * Feature that determines whether {@link java.util.Map} entries are first |
| * sorted by key before serialization or not: if enabled, additional sorting |
| * step is performed if necessary (not necessary for {@link java.util.SortedMap}s), |
| * if disabled, no additional sorting is needed. |
| *<p> |
| * Feature is disabled by default. |
| */ |
| ORDER_MAP_ENTRIES_BY_KEYS(false), |
| |
| /* |
| /****************************************************** |
| /* Other |
| /****************************************************** |
| */ |
| |
| /** |
| * Feature that determines whether {@link ObjectWriter} should |
| * try to eagerly fetch necessary {@link JsonSerializer} when |
| * possible. This improves performance in cases where similarly |
| * configured {@link ObjectWriter} instance is used multiple |
| * times; and should not significantly affect single-use cases. |
| *<p> |
| * Note that there should not be any need to normally disable this |
| * feature: only consider that if there are actual perceived problems. |
| *<p> |
| * Feature is enabled by default. |
| * |
| * @since 2.1 |
| */ |
| EAGER_SERIALIZER_FETCH(true) |
| ; |
| |
| private final boolean _defaultState; |
| |
| private SerializationFeature(boolean defaultState) { |
| _defaultState = defaultState; |
| } |
| |
| @Override |
| public boolean enabledByDefault() { return _defaultState; } |
| |
| @Override |
| public int getMask() { return (1 << ordinal()); } |
| } |
