Package groovy.json

Class JsonGenerator.Options

java.lang.Object
groovy.json.JsonGenerator.Options
Enclosing interface:
JsonGenerator

public static class JsonGenerator.Options
extends Object
A builder used to construct a JsonGenerator instance that allows control over the serialized JSON output. If you do not need to customize the output it is recommended to use the static JsonOutput.toJson methods.

Example:


     def generator = new groovy.json.JsonGenerator.Options()
                         .excludeNulls()
                         .dateFormat('yyyy')
                         .excludeFieldsByName('bar', 'baz')
                         .excludeFieldsByType(java.sql.Date)
                         .build()

     def input = [foo: null, lastUpdated: Date.parse('yyyy-MM-dd', '2014-10-24'),
                   bar: 'foo', baz: 'foo', systemDate: new java.sql.Date(new Date().getTime())]

     assert generator.toJson(input) == '{"lastUpdated":"2014"}'
 
Since:
2.5.0
  • Field Details

    • JSON_DATE_FORMAT

      protected static final String JSON_DATE_FORMAT
      See Also:
      Constant Field Values
    • JSON_DATE_FORMAT_LOCALE

      protected static final Locale JSON_DATE_FORMAT_LOCALE
    • DEFAULT_TIMEZONE

      protected static final String DEFAULT_TIMEZONE
      See Also:
      Constant Field Values
    • excludeNulls

      protected boolean excludeNulls
    • disableUnicodeEscaping

      protected boolean disableUnicodeEscaping
    • dateFormat

      protected String dateFormat
    • dateLocale

      protected Locale dateLocale
    • timezone

      protected TimeZone timezone
    • converters

      protected final Set<JsonGenerator.Converter> converters
    • excludedFieldNames

      protected final Set<String> excludedFieldNames
    • excludedFieldTypes

      protected final Set<Class<?>> excludedFieldTypes
  • Constructor Details

    • Options

      public Options()
  • Method Details

    • excludeNulls

      public JsonGenerator.Options excludeNulls()
      Do not serialize null values.
      Returns:
      a reference to this Options instance
    • disableUnicodeEscaping

      public JsonGenerator.Options disableUnicodeEscaping()
      Disables the escaping of Unicode characters in JSON String values.
      Returns:
      a reference to this Options instance
    • dateFormat

      public JsonGenerator.Options dateFormat​(String format)
      Sets the date format that will be used to serialize Date objects. This must be a valid pattern for SimpleDateFormat and the date formatter will be constructed with the default locale of Locale.US.
      Parameters:
      format - date format pattern used to serialize dates
      Returns:
      a reference to this Options instance
      Throws:
      NullPointerException - if the given pattern is null
      IllegalArgumentException - if the given pattern is invalid
    • dateFormat

      public JsonGenerator.Options dateFormat​(String format, Locale locale)
      Sets the date format that will be used to serialize Date objects. This must be a valid pattern for SimpleDateFormat.
      Parameters:
      format - date format pattern used to serialize dates
      locale - the locale whose date format symbols will be used
      Returns:
      a reference to this Options instance
      Throws:
      IllegalArgumentException - if the given pattern is invalid
    • timezone

      public JsonGenerator.Options timezone​(String timezone)
      Sets the time zone that will be used to serialize dates.
      Parameters:
      timezone - used to serialize dates
      Returns:
      a reference to this Options instance
      Throws:
      NullPointerException - if the given timezone is null
    • addConverter

      public JsonGenerator.Options addConverter​(JsonGenerator.Converter converter)
      Registers a converter that will be called when a type it handles is encountered.
      Parameters:
      converter - to register
      Returns:
      a reference to this Options instance
    • addConverter

      public <T> JsonGenerator.Options addConverter​(Class<T> type, Closure<?> closure)
      Registers a closure that will be called when the specified type or subtype is serialized.

      The closure must accept either 1 or 2 parameters. The first parameter is required and will be instance of the type for which the closure is registered. The second optional parameter should be of type String and, if available, will be passed the name of the key associated with this value if serializing a JSON Object. This parameter will be null when serializing a JSON Array or when there is no way to determine the name of the key.

      Example:

      
           def generator = new groovy.json.JsonGenerator.Options()
                               .addConverter(URL) { URL u ->
                                   u.getHost()
                               }
                               .build()
      
           def input = [domain: new URL('http://groovy-lang.org/json.html#_parser_variants')]
      
           assert generator.toJson(input) == '{"domain":"groovy-lang.org"}'
       

      If two or more closures are registered for the exact same type the last closure based on the order they were specified will be used. When serializing an object its type is compared to the list of registered types in the order the were given and the closure for the first suitable type will be called. Therefore, it is important to register more specific types first.

      Type Parameters:
      T - the type this converter is registered to handle
      Parameters:
      type - the type to convert
      closure - called when the registered type or any type assignable to the given type is encountered
      Returns:
      a reference to this Options instance
      Throws:
      NullPointerException - if the given type or closure is null
      IllegalArgumentException - if the given closure does not accept a parameter of the given type
    • excludeFieldsByName

      public JsonGenerator.Options excludeFieldsByName​(CharSequence... fieldNames)
      Excludes from the output any fields that match the specified names.
      Parameters:
      fieldNames - name of the field to exclude from the output
      Returns:
      a reference to this Options instance
    • excludeFieldsByName

      public JsonGenerator.Options excludeFieldsByName​(Iterable<? extends CharSequence> fieldNames)
      Excludes from the output any fields that match the specified names.
      Parameters:
      fieldNames - collection of names to exclude from the output
      Returns:
      a reference to this Options instance
    • excludeFieldsByType

      public JsonGenerator.Options excludeFieldsByType​(Class<?>... types)
      Excludes from the output any fields whose type is the same or is assignable to any of the given types.
      Parameters:
      types - excluded from the output
      Returns:
      a reference to this Options instance
    • excludeFieldsByType

      public JsonGenerator.Options excludeFieldsByType​(Iterable<Class<?>> types)
      Excludes from the output any fields whose type is the same or is assignable to any of the given types.
      Parameters:
      types - collection of types to exclude from the output
      Returns:
      a reference to this Options instance
    • build

      public JsonGenerator build()
      Creates a JsonGenerator that is based on the current options.
      Returns:
      a fully configured JsonGenerator