Serializer of Nit objects to Json string.

Introduced properties

protected fun current_object=(current_object: nullable Object)

json :: JsonSerializer :: current_object=

fun plain_json: Bool

json :: JsonSerializer :: plain_json

Write plain JSON? Standard JSON without metadata for deserialization
fun plain_json=(plain_json: Bool)

json :: JsonSerializer :: plain_json=

Write plain JSON? Standard JSON without metadata for deserialization
fun pretty_json: Bool

json :: JsonSerializer :: pretty_json

Write pretty JSON for human eyes?
fun pretty_json=(pretty_json: Bool)

json :: JsonSerializer :: pretty_json=

Write pretty JSON for human eyes?
fun stream: Writer

json :: JsonSerializer :: stream

Target writing stream
protected fun stream=(stream: Writer)

json :: JsonSerializer :: stream=

Target writing stream

Redefined properties

redef type SELF: JsonSerializer

json $ JsonSerializer :: SELF

Type of this instance, automatically specialized in every class
redef fun current_object: nullable Object

json $ JsonSerializer :: current_object

The object currently serialized by serialized
redef init init(stream: Writer)

json $ JsonSerializer :: init

redef fun serialize(object: nullable Serializable)

json $ JsonSerializer :: serialize

Entry point method of this service, serialize the object
redef fun serialize_attribute(name: String, value: nullable Object)

json $ JsonSerializer :: serialize_attribute

Serialize an attribute to compose a serializable object
redef fun serialize_reference(object: Serializable)

json $ JsonSerializer :: serialize_reference

Serialize an object, with full serialization or a simple reference

All properties

fun !=(other: nullable Object): Bool

core :: Object :: !=

Have self and other different values?
fun ==(other: nullable Object): Bool

core :: Object :: ==

Have self and other the same value?
type CLASS: Class[SELF]

core :: Object :: CLASS

The type of the class of self.
type SELF: Object

core :: Object :: SELF

Type of this instance, automatically specialized in every class
fun cache: SerializerCache

serialization :: CachingSerializer :: cache

Cache of known objects
fun cache=(cache: SerializerCache)

serialization :: CachingSerializer :: cache=

Cache of known objects
protected fun class_factory(name: String): CLASS

core :: Object :: class_factory

Implementation used by get_class to create the specific class.
fun class_name: String

core :: Object :: class_name

The class name of the object.
protected abstract fun current_object: nullable Object

serialization :: Serializer :: current_object

The object currently serialized by serialized
protected fun current_object=(current_object: nullable Object)

json :: JsonSerializer :: current_object=

fun get_class: CLASS

core :: Object :: get_class

The meta-object representing the dynamic type of self.
fun hash: Int

core :: Object :: hash

The hash code of the object.
init init

core :: Object :: init

fun inspect: String

core :: Object :: inspect

Developer readable representation of self.
protected fun inspect_head: String

core :: Object :: inspect_head

Return "CLASSNAME:#OBJECTID".
intern fun is_same_instance(other: nullable Object): Bool

core :: Object :: is_same_instance

Return true if self and other are the same instance (i.e. same identity).
fun is_same_serialized(other: nullable Object): Bool

core :: Object :: is_same_serialized

Is self the same as other in a serialization context?
intern fun is_same_type(other: Object): Bool

core :: Object :: is_same_type

Return true if self and other have the same dynamic type.
intern fun object_id: Int

core :: Object :: object_id

An internal hash code for the object based on its identity.
fun output

core :: Object :: output

Display self on stdout (debug only).
intern fun output_class_name

core :: Object :: output_class_name

Display class name on stdout (debug only).
fun plain_json: Bool

json :: JsonSerializer :: plain_json

Write plain JSON? Standard JSON without metadata for deserialization
fun plain_json=(plain_json: Bool)

json :: JsonSerializer :: plain_json=

Write plain JSON? Standard JSON without metadata for deserialization
fun pretty_json: Bool

json :: JsonSerializer :: pretty_json

Write pretty JSON for human eyes?
fun pretty_json=(pretty_json: Bool)

json :: JsonSerializer :: pretty_json=

Write pretty JSON for human eyes?
fun serialization_hash: Int

core :: Object :: serialization_hash

Hash value use for serialization
abstract fun serialize(object: nullable Serializable)

serialization :: Serializer :: serialize

Entry point method of this service, serialize the object
fun serialize_attribute(name: String, value: nullable Object)

serialization :: Serializer :: serialize_attribute

Serialize an attribute to compose a serializable object
fun serialize_core(value: Serializable)

serialization :: Serializer :: serialize_core

The method is called when a standard value is serialized
protected abstract fun serialize_reference(object: Serializable)

serialization :: Serializer :: serialize_reference

Serialize an object, with full serialization or a simple reference
fun stream: Writer

json :: JsonSerializer :: stream

Target writing stream
protected fun stream=(stream: Writer)

json :: JsonSerializer :: stream=

Target writing stream
intern fun sys: Sys

core :: Object :: sys

Return the global sys object, the only instance of the Sys class.
abstract fun to_jvalue(env: JniEnv): JValue

core :: Object :: to_jvalue

fun to_s: String

core :: Object :: to_s

User readable representation of self.
fun try_to_serialize(value: nullable Object): Bool

serialization :: Serializer :: try_to_serialize

Serialize value is possible, i.e. it is Serializable or null
fun warn(msg: String)

serialization :: Serializer :: warn

Warn of problems and potential errors (such as if an attribute
package_diagram json::JsonSerializer JsonSerializer serialization::CachingSerializer CachingSerializer json::JsonSerializer->serialization::CachingSerializer serialization::Serializer Serializer serialization::CachingSerializer->serialization::Serializer ...serialization::Serializer ... ...serialization::Serializer->serialization::Serializer serialization::RestrictedJsonSerializer RestrictedJsonSerializer serialization::RestrictedJsonSerializer->json::JsonSerializer

Ancestors

interface Object

core :: Object

The root of the class hierarchy.
interface Serializer

serialization :: Serializer

Abstract serialization service to be sub-classed by specialized services.

Parents

abstract class CachingSerializer

serialization :: CachingSerializer

A Serializer with a cache

Children

class RestrictedJsonSerializer

serialization :: RestrictedJsonSerializer

Extends JsonSerializer and adds specific business behaviors when dealing with business objects.

Class definitions

json $ JsonSerializer
# Serializer of Nit objects to Json string.
class JsonSerializer
	super CachingSerializer

	# Target writing stream
	var stream: Writer

	# Write plain JSON? Standard JSON without metadata for deserialization
	#
	# If `false`, the default, serialize to support deserialization:
	#
	# * Write metadata, including the types of the serialized objects so they can
	#   be deserialized to their original form using `JsonDeserializer`.
	# * Use references when an object has already been serialized so to not duplicate it.
	# * Support cycles in references.
	# * Preserve the Nit `Char` and `Byte` types as special objects.
	# * The generated JSON is standard and can be read by non-Nit programs.
	#   However, some Nit types are not represented by the simplest possible JSON representation.
	#   With the added metadata, it can be complex to read.
	#
	# If `true`, serialize for other programs:
	#
	# * Nit objects are serialized to pure and standard JSON so they can
	#   be easily read by non-Nit programs and humans.
	# * Nit objects are serialized for every references, so they can be duplicated.
	#   It is easier to read but it creates a larger output.
	# * Does not support cycles, will replace the problematic references by `null`.
	# * Does not serialize the metadata needed to deserialize the objects
	#   back to regular Nit objects.
	# * Keys of Nit `HashMap` are converted to their string representation using `to_s`.
	var plain_json = false is writable

	# Write pretty JSON for human eyes?
	#
	# Toggles skipping lines between attributes of an object and
	# properly indent the written JSON.
	var pretty_json = false is writable

	# Current indentation level used for writing `pretty_json`
	private var indent_level = 0

	# List of the current open objects, the first is the main target of the serialization
	#
	# Used only when `plain_json == true` to detect cycles in serialization.
	private var open_objects = new Array[Object]

	# Has the first attribute of the current object already been serialized?
	#
	# Used only when `plain_json == true`.
	private var first_attribute = false

	redef var current_object = null

	redef fun serialize(object)
	do
		if object == null then
			stream.write "null"
		else
			if plain_json then
				for o in open_objects do
					if object.is_same_serialized(o) then
						# Cycle, can't be managed in plain json
						warn "Cycle detected in serialized object, replacing reference with 'null'."
						stream.write "null"
						return
					end
				end

				open_objects.add object
			end

			first_attribute = true
			var last_object = current_object
			current_object = object
			object.accept_json_serializer self
			first_attribute = false
			current_object = last_object

			if plain_json then open_objects.pop
		end
	end

	redef fun serialize_attribute(name, value)
	do
		if not plain_json or not first_attribute then
			stream.write ","
		end
		first_attribute = false

		new_line_and_indent
		stream.write "\""
		stream.write name
		stream.write "\":"
		if pretty_json then stream.write " "
		super
	end

	redef fun serialize_reference(object)
	do
		if not plain_json and cache.has_object(object) then
			# if already serialized, add local reference
			var id = cache.id_for(object)
			stream.write "\{"
			indent_level += 1
			new_line_and_indent
			stream.write "\"__kind\": \"ref\", \"__id\": "
			stream.write id.to_s
			indent_level -= 1
			new_line_and_indent
			stream.write "\}"
		else
			# serialize here
			serialize object
		end
	end

	# Write a new line and indent it, only if `pretty_json`
	private fun new_line_and_indent
	do
		if pretty_json then
			stream.write "\n"
			for i in indent_level.times do stream.write "\t"
		end
	end
end
lib/json/serialization_write.nit:21,1--145,3