#region Header
/**
* JsonMapper.cs
* JSON to .Net object and object to JSON conversions.
*
* The authors disclaim copyright to this source code. For more details, see
* the COPYING file included with this distribution.
**/
#endregion
using System;
using System.Collections;
using System.Collections.Generic;
using System.Globalization;
using System.IO;
using System.Reflection;
namespace LitJson{
internal struct PropertyMetadata
{
public MemberInfo Info;
public bool IsField;
public Type Type;
}
internal struct ArrayMetadata
{
private Type element_type;
private bool is_array;
private bool is_list;
public Type ElementType {
get {
if (element_type == null)
return typeof (JsonData);
return element_type;
}
set { element_type = value; }
}
public bool IsArray {
get { return is_array; }
set { is_array = value; }
}
public bool IsList {
get { return is_list; }
set { is_list = value; }
}
}
internal struct ObjectMetadata
{
private Type element_type;
private bool is_dictionary;
private IDictionary<string, PropertyMetadata> properties;
public Type ElementType {
get {
if (element_type == null)
return typeof (JsonData);
return element_type;
}
set { element_type = value; }
}
public bool IsDictionary {
get { return is_dictionary; }
set { is_dictionary = value; }
}
public IDictionary<string, PropertyMetadata> Properties {
get { return properties; }
set { properties = value; }
}
}
internal delegate void ExporterFunc (object obj, JsonWriter writer);
public delegate void ExporterFunc<T> (T obj, JsonWriter writer);
internal delegate object ImporterFunc (object input);
public delegate TValue ImporterFunc<TJson, TValue> (TJson input);
public delegate IJsonWrapper WrapperFactory ();
public class JsonMapper
{
#region Fields
private static int max_nesting_depth;
private static IFormatProvider datetime_format;
private static IDictionary<Type, ExporterFunc> base_exporters_table;
private static IDictionary<Type, ExporterFunc> custom_exporters_table;
private static IDictionary<Type,
IDictionary<Type, ImporterFunc>> base_importers_table;
private static IDictionary<Type,
IDictionary<Type, ImporterFunc>> custom_importers_table;
private static IDictionary<Type, ArrayMetadata> array_metadata;
private static readonly object array_metadata_lock = new Object ();
private static IDictionary<Type,
IDictionary<Type, MethodInfo>> conv_ops;
private static readonly object conv_ops_lock = new Object ();
private static IDictionary<Type, ObjectMetadata> object_metadata;
private static readonly object object_metadata_lock = new Object ();
private static IDictionary<Type,
IList<PropertyMetadata>> type_properties;
private static readonly object type_properties_lock = new Object ();
private static JsonWriter static_writer;
private static readonly object static_writer_lock = new Object ();
#endregion
#region Constructors
static JsonMapper ()
{
max_nesting_depth = 100;
array_metadata = new Dictionary<Type, ArrayMetadata> ();
conv_ops = new Dictionary<Type, IDictionary<Type, MethodInfo>> ();
object_metadata = new Dictionary<Type, ObjectMetadata> ();
type_properties = new Dictionary<Type,
IList<PropertyMetadata>> ();
static_writer = new JsonWriter ();
datetime_format = DateTimeFormatInfo.InvariantInfo;
base_exporters_table = new Dictionary<Type, ExporterFunc> ();
custom_exporters_table = new Dictionary<Type, ExporterFunc> ();
base_importers_table = new Dictionary<Type,
IDictionary<Type, ImporterFunc>> ();
custom_importers_table = new Dictionary<Type,
IDictionary<Type, ImporterFunc>> ();
RegisterBaseExporters ();
RegisterBaseImporters ();
}
#endregion
#region Private Methods
private static void AddArrayMetadata (Type type)
{
if (array_metadata.ContainsKey (type))
return;
ArrayMetadata data = new ArrayMetadata ();
data.IsArray = type.IsArray;
if (type.GetInterface ("System.Collections.IList") != null)
data.IsList = true;
foreach (PropertyInfo p_info in type.GetProperties ()) {
if (p_info.Name != "Item")
continue;
ParameterInfo[] parameters = p_info.GetIndexParameters ();
if (parameters.Length != 1)
continue;
if (parameters[0].ParameterType == typeof (int))
data.ElementType = p_info.PropertyType;
}
lock (array_metadata_lock) {
try {
array_metadata.Add (type, data);
} catch (ArgumentException) {
return;
}
}
}
private static void AddObjectMetadata (Type type)
{
if (object_metadata.ContainsKey (type))
return;
ObjectMetadata data = new ObjectMetadata ();
if (type.GetInterface ("System.Collections.IDictionary") != null)
data.IsDictionary = true;
data.Properties = new Dictionary<string, PropertyMetadata> ();
foreach (PropertyInfo p_info in type.GetProperties ()) {
if (p_info.Name == "Item") {
ParameterInfo[] parameters = p_info.GetIndexParameters ();
if (parameters.Length != 1)
continue;
if (parameters[0].ParameterType == typeof (string))
data.ElementType = p_info.PropertyType;
continue;
}
PropertyMetadata p_data = new PropertyMetadata ();
p_data.Info = p_info;
p_data.Type = p_info.PropertyType;
data.Properties.Add (p_info.Name, p_data);
}
foreach (FieldInfo f_info in type.GetFields ()) {
PropertyMetadata p_data = new PropertyMetadata ();
p_data.Info = f_info;
p_data.IsField = true;
p_data.Type = f_info.FieldType;
data.Properties.Add (f_info.Name, p_data);
}
lock (object_metadata_lock) {
try {
object_metadata.Add (type, data);
} catch (ArgumentException) {
return;
}
}
}
private static void AddTypeProperties (Type type)
{
if (type_properties.ContainsKey (type))
return;
IList<PropertyMetadata> props = new List<PropertyMetadata> ();
foreach (PropertyInfo p_info in type.GetProperties ()) {
if (p_info.Name == "Item")
continue;
PropertyMetadata p_data = new PropertyMetadata ();
p_data.Info = p_info;
p_data.IsField = false;
props.Add (p_data);
}
foreach (FieldInfo f_info in type.GetFields ()) {
PropertyMetadata p_data = new PropertyMetadata ();
p_data.Info = f_info;
p_data.IsField = true;
props.Add (p_data);
}
lock (type_properties_lock) {
try {
type_properties.Add (type, props);
} catch (ArgumentException) {
return;
}
}
}
private static MethodInfo GetConvOp (Type t1, Type t2)
{
lock (conv_ops_lock) {
if (! conv_ops.ContainsKey (t1))
conv_ops.Add (t1, new Dictionary<Type, MethodInfo> ());
}
if (conv_ops[t1].ContainsKey (t2))
return conv_ops[t1][t2];
MethodInfo op = t1.GetMethod (
"op_Implicit", new Type[] { t2 });
lock (conv_ops_lock) {
try {
conv_ops[t1].Add (t2, op);
} catch (ArgumentException) {
return conv_ops[t1][t2];
}
}
return op;
}
private static object ReadValue (Type inst_type, JsonReader reader)
{
reader.Read ();
if (reader.Token == JsonToken.ArrayEnd)
return null;
if (reader.Token == JsonToken.Null) {
if (! inst_type.IsClass)
throw new JsonException (String.Format (
"Can't assign null to an instance of type {0}",
inst_type));
return null;
}
if (reader.Token == JsonToken.Double ||
reader.Token == JsonToken.Int ||
reader.Token == JsonToken.Long ||
reader.Token == JsonToken.String ||
reader.Token == JsonToken.Boolean) {
Type json_type = reader.Value.GetType ();
if (inst_type.IsAssignableFrom (json_type))
return reader.Value;
// If there's a custom importer that fits, use it
if (custom_importers_table.ContainsKey (json_type) &&
custom_importers_table[json_type].ContainsKey (
inst_type)) {
ImporterFunc importer =
custom_importers_table[json_type][inst_type];
return importer (reader.Value);
}
// Maybe there's a base importer that works
if (base_importers_table.ContainsKey (json_type) &&
base_importers_table[json_type].ContainsKey (
inst_type)) {
ImporterFunc importer =
base_importers_table[json_type][inst_type];
return importer (reader.Value);
}
// Maybe it's an enum
if (inst_type.IsEnum)
return Enum.ToObject (inst_type, reader.Value);
// Try using an implicit conversion operator
MethodInfo conv_op = GetConvOp (inst_type, json_type);
if (conv_op != null)
return conv_op.Invoke (null,
new object[] { reader.Value });
// No luck
throw new JsonException (String.Format (
"Can't assign value '{0}' (type {1}) to type {2}",
reader.Value, json_type, inst_type));
}
object instance = null;
if (reader.Token == JsonToken.ArrayStart) {
AddArrayMetadata (inst_type);
ArrayMetadata t_data = array_metadata[inst_type];
if (! t_data.IsArray && ! t_data.IsList)
throw new JsonException (String.Format (
"Type {0} can't act as an array",
inst_type));
IList list;
Type elem_type;
if (! t_data.IsArray) {
list = (IList) Activator.CreateInstance (inst_type);
elem_type = t_data.ElementType;
} else {
list = new ArrayList ();
elem_type = inst_type.GetElementType ();
}
while (true) {
object item = ReadValue (elem_type, reader);
if (reader.Token == JsonToken.ArrayEnd)
break;
list.Add (item);
}
if (t_data.IsArray) {
int n = list.Count;
instance = Array.CreateInstance (elem_type, n);
for (int i = 0; i < n; i++)
((Array) instance).SetValue (list[i], i);
} else
instance = list;
} else if (reader.Token == JsonToken.ObjectStart) {
AddObjectMetadata (inst_type);
ObjectMetadata t_data = object_metadata[inst_type];
instance = Activator.CreateInstance (inst_type);
while (true) {
reader.Read ();
if (reader.Token == JsonToken.ObjectEnd)
break;
string property = (string) reader.Value;
if (t_data.Properties.ContainsKey (property)) {
PropertyMetadata prop_data =
t_data.Properties[property];
if (prop_data.IsField) {
((FieldInfo) prop_data.Info).SetValue (
instance, ReadValue (prop_data.Type, reader));
} else {
PropertyInfo p_info =
(PropertyInfo) prop_data.Info;
if (p_info.CanWrite)
p_info.SetValue (
instance,
ReadValue (prop_data.Type, reader),
null);
else
ReadValue (prop_data.Type, reader);
}
} else {
if (! t_data.IsDictionary)
throw new JsonException (String.Format (
"The type {0} doesn't have the " +
"property '{1}'", inst_type, property));
((IDictionary) instance).Add (
property, ReadValue (
t_data.ElementType, reader));
}
}
}
return instance;
}
private static IJsonWrapper ReadValue (WrapperFactory factory,
JsonReader reader)
{
reader.Read ();
if (reader.Token == JsonToken.ArrayEnd ||
reader.Token == JsonToken.Null)
return null;
IJsonWrapper instance = factory ();
if (reader.Token == JsonToken.String) {
instance.SetString ((string) reader.Value);
return instance;
}
if (reader.Token == JsonToken.Double) {
instance.SetDouble ((double) reader.Value);
return instance;
}
if (reader.Token == JsonToken.Int) {
instance.SetInt ((int) reader.Value);
return instance;
}
if (reader.Token == JsonToken.Long) {
instance.SetLong ((long) reader.Value);
return instance;
}
if (reader.Token == JsonToken.Boolean) {
instance.SetBoolean ((bool) reader.Value);
return instance;
}
if (reader.Token == JsonToken.ArrayStart) {
instance.SetJsonType (JsonType.Array);
while (true) {
IJsonWrapper item = ReadValue (factory, reader);
if (reader.Token == JsonToken.ArrayEnd)
break;
((IList) instance).Add (item);
}
}
else if (reader.Token == JsonToken.ObjectStart) {
instance.SetJsonType (JsonType.Object);
while (true) {
reader.Read ();
if (reader.Token == JsonToken.ObjectEnd)
break;
string property = (string) reader.Value;
((IDictionary) instance)[property] = ReadValue (
factory, reader);
}
}
return instance;
}
private static void RegisterBaseExporters ()
{
base_exporters_table[typeof (byte)] =
delegate (object obj, JsonWriter writer) {
writer.Write (Convert.ToInt32 ((byte) obj));
};
base_exporters_table[typeof (char)] =
delegate (object obj, JsonWriter writer) {
writer.Write (Convert.ToString ((char) obj));
};
base_exporters_table[typeof (DateTime)] =
delegate (object obj, JsonWriter writer) {
writer.Write (Convert.ToString ((DateTime) obj,
datetime_format));
};
base_exporters_table[typeof (decimal)] =
delegate (object obj, JsonWriter writer) {
writer.Write ((decimal) obj);
};
base_exporters_table[typeof (sbyte)] =
delegate (object obj, JsonWriter writer) {
writer.Write (Convert.ToInt32 ((sbyte) obj));
};
base_exporters_table[typeof (short)] =
delegate (object obj, JsonWriter writer) {
writer.Write (Convert.ToInt32 ((short) obj));
};
base_exporters_table[typeof (ushort)] =
delegate (object obj, JsonWriter writer) {
writer.Write (Convert.ToInt32 ((ushort) obj));
};
base_exporters_table[typeof (uint)] =
delegate (object obj, JsonWriter writer) {
writer.Write (Convert.ToUInt64 ((uint) obj));
};
base_exporters_table[typeof (ulong)] =
delegate (object obj, JsonWriter writer) {
writer.Write ((ulong) obj);
};
}
private static void RegisterBaseImporters ()
{
ImporterFunc importer;
importer = delegate (object input) {
return Convert.ToByte ((int) input);
};
RegisterImporter (base_importers_table, typeof (int),
typeof (byte), importer);
importer = delegate (object input) {
return Convert.ToUInt64 ((int) input);
};
RegisterImporter (base_importers_table, typeof (int),
typeof (ulong), importer);
importer = delegate (object input) {
return Convert.ToSByte ((int) input);
};
RegisterImporter (base_importers_table, typeof (int),
typeof (sbyte), importer);
importer = delegate (object input) {
return Convert.ToInt16 ((int) input);
};
RegisterImporter (base_importers_table, typeof (int),
typeof (short), importer);
importer = delegate (object input) {
return Convert.ToUInt16 ((int) input);
};
RegisterImporter (base_importers_table, typeof (int),
typeof (ushort), importer);
importer = delegate (object input) {
return Convert.ToUInt32 ((int) input);
};
RegisterImporter (base_importers_table, typeof (int),
typeof (uint), importer);
importer = delegate (object input) {
return Convert.ToSingle ((int) input);
};
RegisterImporter (base_importers_table, typeof (int),
typeof (float), importer);
importer = delegate (object input) {
return Convert.ToDouble ((int) input);
};
RegisterImporter (base_importers_table, typeof (int),
typeof (double), importer);
importer = delegate (object input) {
return Convert.ToDecimal ((double) input);
};
RegisterImporter (base_importers_table, typeof (double),
typeof (decimal), importer);
importer = delegate (object input) {
return Convert.ToUInt32 ((long) input);
};
RegisterImporter (base_importers_table, typeof (long),
typeof (uint), importer);
importer = delegate (object input) {
return Convert.ToChar ((string) input);
};
RegisterImporter (base_importers_table, typeof (string),
typeof (char), importer);
importer = delegate (object input) {
return Convert.ToDateTime ((string) input, datetime_format);
};
RegisterImporter (base_importers_table, typeof (string),
typeof (DateTime), importer);
}
private static void RegisterImporter (
IDictionary<Type, IDictionary<Type, ImporterFunc>> table,
Type json_type, Type value_type, ImporterFunc importer)
{
if (! table.ContainsKey (json_type))
table.Add (json_type, new Dictionary<Type, ImporterFunc> ());
table[json_type][value_type] = importer;
}
private static void WriteValue (object obj, JsonWriter writer,
bool writer_is_private,
int depth)
{
if (depth > max_nesting_depth)
throw new JsonException (
String.Format ("Max allowed object depth reached while " +
"trying to export from type {0}",
obj.GetType ()));
if (obj == null) {
writer.Write (null);
return;
}
if (obj is IJsonWrapper) {
if (writer_is_private)
writer.TextWriter.Write (((IJsonWrapper) obj).ToJson ());
else
((IJsonWrapper) obj).ToJson (writer);
return;
}
if (obj is String) {
writer.Write ((string) obj);
return;
}
if (obj is Double) {
writer.Write ((double) obj);
return;
}
if (obj is Int32) {
writer.Write ((int) obj);
return;
}
if (obj is Boolean) {
writer.Write ((bool) obj);
return;
}
if (obj is Int64) {
writer.Write ((long) obj);
return;
}
if (obj is Array) {
writer.WriteArrayStart ();
foreach (object elem in (Array) obj)
WriteValue (elem, writer, writer_is_private, depth + 1);
writer.WriteArrayEnd ();
return;
}
if (obj is IList) {
writer.WriteArrayStart ();
foreach (object elem in (IList) obj)
WriteValue (elem, writer, writer_is_private, depth + 1);
writer.WriteArrayEnd ();
return;
}
if (obj is IDictionary) {
writer.WriteObjectStart ();
foreach (DictionaryEntry entry in (IDictionary) obj) {
writer.WritePropertyName ((string) entry.Key);
WriteValue (entry.Value, writer, writer_is_private,
depth + 1);
}
writer.WriteObjectEnd ();
return;
}
Type obj_type = obj.GetType ();
// See if there's a custom exporter for the object
if (custom_exporters_table.ContainsKey (obj_type)) {
ExporterFunc exporter = custom_exporters_table[obj_type];
exporter (obj, writer);
return;
}
// If not, maybe there's a base exporter
if (base_exporters_table.ContainsKey (obj_type)) {
ExporterFunc exporter = base_exporters_table[obj_type];
exporter (obj, writer);
return;
}
// Last option, let's see if it's an enum
if (obj is Enum) {
Type e_type = Enum.GetUnderlyingType (obj_type);
if (e_type == typeof (long)
|| e_type == typeof (uint)
|| e_type == typeof (ulong))
writer.Write ((ulong) obj);
else
writer.Write ((int) obj);
return;
}
// Okay, so it looks like the input should be exported as an
// object
AddTypeProperties (obj_type);
IList<PropertyMetadata> props = type_properties[obj_type];
writer.WriteObjectStart ();
foreach (PropertyMetadata p_data in props) {
if (p_data.IsField) {
writer.WritePropertyName (p_data.Info.Name);
WriteValue (((FieldInfo) p_data.Info).GetValue (obj),
writer, writer_is_private, depth + 1);
}
else {
PropertyInfo p_info = (PropertyInfo) p_data.Info;
if (p_info.CanRead) {
writer.WritePropertyName (p_data.Info.Name);
WriteValue (p_info.GetValue (obj, null),
writer, writer_is_private, depth + 1);
}
}
}
writer.WriteObjectEnd ();
}
#endregion
public static string ToJson (object obj)
{
lock (static_writer_lock) {
static_writer.Reset ();
WriteValue (obj, static_writer, true, 0);
return static_writer.ToString ();
}
}
public static void ToJson (object obj, JsonWriter writer)
{
WriteValue (obj, writer, false, 0);
}
public static JsonData ToObject (JsonReader reader)
{
return (JsonData) ToWrapper (
delegate { return new JsonData (); }, reader);
}
public static JsonData ToObject (TextReader reader)
{
JsonReader json_reader = new JsonReader (reader);
return (JsonData) ToWrapper (
delegate { return new JsonData (); }, json_reader);
}
public static JsonData ToObject (string json)
{
return (JsonData) ToWrapper (
delegate { return new JsonData (); }, json);
}
public static T ToObject<T> (JsonReader reader)
{
return (T) ReadValue (typeof (T), reader);
}
public static T ToObject<T> (TextReader reader)
{
JsonReader json_reader = new JsonReader (reader);
return (T) ReadValue (typeof (T), json_reader);
}
public static T ToObject<T> (string json)
{
JsonReader reader = new JsonReader (json);
return (T) ReadValue (typeof (T), reader);
}
public static IJsonWrapper ToWrapper (WrapperFactory factory,
JsonReader reader)
{
return ReadValue (factory, reader);
}
public static IJsonWrapper ToWrapper (WrapperFactory factory,
string json)
{
JsonReader reader = new JsonReader (json);
return ReadValue (factory, reader);
}
public static void RegisterExporter<T> (ExporterFunc<T> exporter)
{
ExporterFunc exporter_wrapper =
delegate (object obj, JsonWriter writer) {
exporter ((T) obj, writer);
};
custom_exporters_table[typeof (T)] = exporter_wrapper;
}
public static void RegisterImporter<TJson, TValue> (
ImporterFunc<TJson, TValue> importer)
{
ImporterFunc importer_wrapper =
delegate (object input) {
return importer ((TJson) input);
};
RegisterImporter (custom_importers_table, typeof (TJson),
typeof (TValue), importer_wrapper);
}
public static void UnregisterExporters ()
{
custom_exporters_table.Clear ();
}
public static void UnregisterImporters ()
{
custom_importers_table.Clear ();
}
}
}
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