Class JSONDeserializer

java.lang.Object
nonapi.io.github.classgraph.json.JSONDeserializer

public class JSONDeserializer extends Object
Fast, lightweight Java object to JSON serializer, and JSON to Java object deserializer. Handles cycles in the object graph by inserting reference ids.
  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Class
    Description
    private static class 
    Used to hold object instantiations temporarily before their fields can be populated, so that object references can be resolved in the same order during deserialization as they were created during serialization.
  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    private
    Constructor.
  • Method Summary

    Modifier and Type
    Method
    Description
    static <T> T
    deserializeObject(Class<T> expectedType, String json)
    Deserialize JSON to a new object graph, with the root object of the specified expected type.
    private static <T> T
    deserializeObject(Class<T> expectedType, String json, ClassFieldCache classFieldCache)
    Deserialize JSON to a new object graph, with the root object of the specified expected type, using or reusing the given type cache.
    static <T> T
    deserializeObject(Class<T> expectedType, String json, ReflectionUtils reflectionUtils)
    Deserialize JSON to a new object graph, with the root object of the specified expected type.
    static void
    deserializeToField(Object containingObject, String fieldName, String json)
    Deserialize JSON to a new object graph, with the root object of the specified expected type, and store the root object in the named field of the given containing object.
    static void
    deserializeToField(Object containingObject, String fieldName, String json, ClassFieldCache classFieldCache)
    Deserialize JSON to a new object graph, with the root object of the specified expected type, and store the root object in the named field of the given containing object.
    static void
    deserializeToField(Object containingObject, String fieldName, String json, ReflectionUtils reflectionUtils)
    Deserialize JSON to a new object graph, with the root object of the specified expected type, and store the root object in the named field of the given containing object.
    private static Map<CharSequence,Object>
    getInitialIdToObjectMap(Object objectInstance, Object parsedJSON)
    Set up the initial mapping from id to object, by adding the id of the toplevel object, if it has an id field in JSON.
    private static Object
    jsonBasicValueToObject(Object jsonVal, Type expectedType, boolean convertStringToNumber)
    Deserialize a JSON basic value (String, Integer, Long, or Double), conforming it to the expected type (Character, Short, etc.).
    private static void
    populateObjectFromJsonObject(Object objectInstance, Type objectResolvedType, Object jsonVal, ClassFieldCache classFieldCache, Map<CharSequence,Object> idToObjectInstance, List<Runnable> collectionElementAdders)
    Populate object from json object.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
  • Constructor Details

    • JSONDeserializer

      private JSONDeserializer()
      Constructor.
  • Method Details

    • jsonBasicValueToObject

      private static Object jsonBasicValueToObject(Object jsonVal, Type expectedType, boolean convertStringToNumber)
      Deserialize a JSON basic value (String, Integer, Long, or Double), conforming it to the expected type (Character, Short, etc.).
      Parameters:
      jsonVal - the json val
      expectedType - the expected type
      convertStringToNumber - if true, convert strings to numbers
      Returns:
      the object
    • populateObjectFromJsonObject

      private static void populateObjectFromJsonObject(Object objectInstance, Type objectResolvedType, Object jsonVal, ClassFieldCache classFieldCache, Map<CharSequence,Object> idToObjectInstance, List<Runnable> collectionElementAdders)
      Populate object from json object.
      Parameters:
      objectInstance - the object instance
      objectResolvedType - the object resolved type
      jsonVal - the json val
      classFieldCache - the class field cache
      idToObjectInstance - a map from id to object instance
      collectionElementAdders - the collection element adders
    • getInitialIdToObjectMap

      private static Map<CharSequence,Object> getInitialIdToObjectMap(Object objectInstance, Object parsedJSON)
      Set up the initial mapping from id to object, by adding the id of the toplevel object, if it has an id field in JSON.
      Parameters:
      objectInstance - the object instance
      parsedJSON - the parsed JSON
      Returns:
      the initial id to object map
    • deserializeObject

      private static <T> T deserializeObject(Class<T> expectedType, String json, ClassFieldCache classFieldCache) throws IllegalArgumentException
      Deserialize JSON to a new object graph, with the root object of the specified expected type, using or reusing the given type cache. Does not work for generic types, since it is not possible to obtain the generic type of a Class reference.
      Type Parameters:
      T - the expected type
      Parameters:
      expectedType - The type that the JSON should conform to.
      json - the JSON string to deserialize.
      classFieldCache - The class field cache. Reusing this cache will increase the speed if many JSON documents of the same type need to be parsed.
      Returns:
      The object graph after deserialization.
      Throws:
      IllegalArgumentException - If anything goes wrong during deserialization.
    • deserializeObject

      public static <T> T deserializeObject(Class<T> expectedType, String json, ReflectionUtils reflectionUtils) throws IllegalArgumentException
      Deserialize JSON to a new object graph, with the root object of the specified expected type. Does not work for generic types, since it is not possible to obtain the generic type of a Class reference.
      Type Parameters:
      T - The type that the JSON should conform to.
      Parameters:
      expectedType - The class reference for the type that the JSON should conform to.
      json - the JSON string to deserialize.
      Returns:
      The object graph after deserialization.
      Throws:
      IllegalArgumentException - If anything goes wrong during deserialization.
    • deserializeObject

      public static <T> T deserializeObject(Class<T> expectedType, String json) throws IllegalArgumentException
      Deserialize JSON to a new object graph, with the root object of the specified expected type. Does not work for generic types, since it is not possible to obtain the generic type of a Class reference.
      Type Parameters:
      T - The type that the JSON should conform to.
      Parameters:
      expectedType - The class reference for the type that the JSON should conform to.
      json - the JSON string to deserialize.
      Returns:
      The object graph after deserialization.
      Throws:
      IllegalArgumentException - If anything goes wrong during deserialization.
    • deserializeToField

      public static void deserializeToField(Object containingObject, String fieldName, String json, ClassFieldCache classFieldCache) throws IllegalArgumentException
      Deserialize JSON to a new object graph, with the root object of the specified expected type, and store the root object in the named field of the given containing object. Works for generic types, since it is possible to obtain the generic type of a field.
      Parameters:
      containingObject - The object containing the named field to deserialize the object graph into.
      fieldName - The name of the field to set with the result.
      json - the JSON string to deserialize.
      classFieldCache - The class field cache. Reusing this cache will increase the speed if many JSON documents of the same type need to be parsed.
      Throws:
      IllegalArgumentException - If anything goes wrong during deserialization.
    • deserializeToField

      public static void deserializeToField(Object containingObject, String fieldName, String json, ReflectionUtils reflectionUtils) throws IllegalArgumentException
      Deserialize JSON to a new object graph, with the root object of the specified expected type, and store the root object in the named field of the given containing object. Works for generic types, since it is possible to obtain the generic type of a field.
      Parameters:
      containingObject - The object containing the named field to deserialize the object graph into.
      fieldName - The name of the field to set with the result.
      json - the JSON string to deserialize.
      Throws:
      IllegalArgumentException - If anything goes wrong during deserialization.
    • deserializeToField

      public static void deserializeToField(Object containingObject, String fieldName, String json) throws IllegalArgumentException
      Deserialize JSON to a new object graph, with the root object of the specified expected type, and store the root object in the named field of the given containing object. Works for generic types, since it is possible to obtain the generic type of a field.
      Parameters:
      containingObject - The object containing the named field to deserialize the object graph into.
      fieldName - The name of the field to set with the result.
      json - the JSON string to deserialize.
      Throws:
      IllegalArgumentException - If anything goes wrong during deserialization.