ValueInstantiator (jackson-databind 2.15.0-rc3)

java.lang.Object
- com.fasterxml.jackson.databind.deser.ValueInstantiator

Direct Known Subclasses:

StdValueInstantiator, ValueInstantiator.Base, ValueInstantiator.Delegating
```
public abstract class ValueInstantiator
extends Object
```
Class that defines simple API implemented by objects that create value instances. Some or all of properties of value instances may be initialized by instantiator, rest being populated by deserializer, to which value instance is passed. Since different kinds of JSON values (structured and scalar) may be bound to Java values, in some cases instantiator fully defines resulting value; this is the case when JSON value is a scalar value (String, number, boolean).
Note that this type is not parameterized (even though it would seemingly make sense), because such type information cannot be use effectively during runtime: access is always using either wildcard type, or just basic Object; and so adding type parameter seems like unnecessary extra work.
Actual implementations are strongly recommended to be based on StdValueInstantiator which implements all methods, and as such will be compatible across versions even if new methods were added to this interface.

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`ValueInstantiator.Base` Partial `ValueInstantiator` implementation that is strongly recommended to be used instead of directly extending `ValueInstantiator` itself.
`static class`	`ValueInstantiator.Delegating` Delegating `ValueInstantiator` implementation meant as a base type that by default delegates methods to specified fallback instantiator.
`static interface`	`ValueInstantiator.Gettable`

Constructor Summary

Constructors
Constructor and Description

ValueInstantiator()

Constructors
Constructor and Description
`ValueInstantiator()`

Method Summary

All Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type	Method and Description
`protected Object`	`_createFromStringFallbacks(DeserializationContext ctxt, String value)` Deprecated. Since 2.12 should not handle coercions here
`boolean`	`canCreateFromBigDecimal()` Method that can be called to check whether a BigDecimal based creator is available to use (to call `createFromBigDecimal(com.fasterxml.jackson.databind.DeserializationContext, java.math.BigDecimal)`).
`boolean`	`canCreateFromBigInteger()` Method that can be called to check whether a BigInteger based creator is available to use (to call `createFromBigInteger(com.fasterxml.jackson.databind.DeserializationContext, java.math.BigInteger)`).
`boolean`	`canCreateFromBoolean()` Method that can be called to check whether a double (boolean / Boolean) based creator is available to use (to call `createFromDouble(com.fasterxml.jackson.databind.DeserializationContext, double)`).
`boolean`	`canCreateFromDouble()` Method that can be called to check whether a double (double / Double) based creator is available to use (to call `createFromDouble(com.fasterxml.jackson.databind.DeserializationContext, double)`).
`boolean`	`canCreateFromInt()` Method that can be called to check whether an integer (int, Integer) based creator is available to use (to call `createFromInt(com.fasterxml.jackson.databind.DeserializationContext, int)`).
`boolean`	`canCreateFromLong()` Method that can be called to check whether a long (long, Long) based creator is available to use (to call `createFromLong(com.fasterxml.jackson.databind.DeserializationContext, long)`).
`boolean`	`canCreateFromObjectWith()` Method that can be called to check whether a property-based creator (argument-taking constructor or factory method) is available to instantiate values from JSON Object
`boolean`	`canCreateFromString()` Method that can be called to check whether a String-based creator is available for this instantiator.
`boolean`	`canCreateUsingArrayDelegate()` Method that can be called to check whether a array-delegate-based creator (single-arg constructor or factory method) is available for this instantiator
`boolean`	`canCreateUsingDefault()` Method that can be called to check whether a default creator (constructor, or no-arg static factory method) is available for this instantiator
`boolean`	`canCreateUsingDelegate()` Method that can be called to check whether a delegate-based creator (single-arg constructor or factory method) is available for this instantiator
`boolean`	`canInstantiate()` Method that will return true if any of `canCreateXxx` method returns true: that is, if there is any way that an instance could be created.
`ValueInstantiator`	`createContextual(DeserializationContext ctxt, BeanDescription beanDesc)` "Contextualization" method that is called after construction but before first use, to allow instantiator access to context needed to possible resolve its dependencies.
`Object`	`createFromBigDecimal(DeserializationContext ctxt, BigDecimal value)`
`Object`	`createFromBigInteger(DeserializationContext ctxt, BigInteger value)`
`Object`	`createFromBoolean(DeserializationContext ctxt, boolean value)`
`Object`	`createFromDouble(DeserializationContext ctxt, double value)`
`Object`	`createFromInt(DeserializationContext ctxt, int value)`
`Object`	`createFromLong(DeserializationContext ctxt, long value)`
`Object`	`createFromObjectWith(DeserializationContext ctxt, Object[] args)` Method called to create value instance from JSON Object when instantiation arguments are passed; this is done, for example when passing information specified with "Creator" annotations.
`Object`	`createFromObjectWith(DeserializationContext ctxt, SettableBeanProperty[] props, PropertyValueBuffer buffer)` Method that delegates to `createFromObjectWith(DeserializationContext, Object[])` by default, but can be overridden if the application should have customized behavior with respect to missing properties.
`Object`	`createFromString(DeserializationContext ctxt, String value)`
`Object`	`createUsingArrayDelegate(DeserializationContext ctxt, Object delegate)` Method to called to create value instance from JSON Array using an intermediate "delegate" value to pass to createor method
`Object`	`createUsingDefault(DeserializationContext ctxt)` Method called to create value instance from a JSON value when no data needs to passed to creator (constructor, factory method); typically this will call the default constructor of the value object.
`Object`	`createUsingDefaultOrWithoutArguments(DeserializationContext ctxt)` Combination of `createUsingDefault(com.fasterxml.jackson.databind.DeserializationContext)` and `createFromObjectWith(DeserializationContext, Object[])` which will call former first, if possible; or latter if possible (with `null` arguments); and if neither works throw an exception.
`Object`	`createUsingDelegate(DeserializationContext ctxt, Object delegate)` Method to called to create value instance from JSON Object using an intermediate "delegate" value to pass to createor method
`AnnotatedWithParams`	`getArrayDelegateCreator()` Method that can be called to try to access member (constructor, static factory method) that is used as the "array delegate creator".
`JavaType`	`getArrayDelegateType(DeserializationConfig config)` Method that can be used to determine what is the type of array delegate type to use, if any; if no delegates are used, will return null.
`AnnotatedWithParams`	`getDefaultCreator()` Method that can be called to try to access member (constructor, static factory method) that is used as the "default creator" (creator that is called without arguments; typically default [zero-argument] constructor of the type).
`AnnotatedWithParams`	`getDelegateCreator()` Method that can be called to try to access member (constructor, static factory method) that is used as the "delegate creator".
`JavaType`	`getDelegateType(DeserializationConfig config)` Method that can be used to determine what is the type of delegate type to use, if any; if no delegates are used, will return null.
`SettableBeanProperty[]`	`getFromObjectArguments(DeserializationConfig config)` Method called to determine types of instantiation arguments to use when creating instances with creator arguments (when `canCreateFromObjectWith()` returns true).
`Class<?>`	`getValueClass()` Accessor for raw (type-erased) type of instances to create.
`String`	`getValueTypeDesc()` Method that returns description of the value type this instantiator handles.
`AnnotatedWithParams`	`getWithArgsCreator()` Method that can be called to try to access member (constructor, static factory method) that is used as the "non-default creator" (constructor or factory method that takes one or more arguments).

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - ValueInstantiator
```
public ValueInstantiator()
```
- Method Detail
  - createContextual
```
public ValueInstantiator createContextual(DeserializationContext ctxt,
                                          BeanDescription beanDesc)
                                   throws JsonMappingException
```
    "Contextualization" method that is called after construction but before first use, to allow instantiator access to context needed to possible resolve its dependencies.
    
    Parameters:
    
    ctxt - Currently active deserialization context: needed to (for example) resolving TypeDeserializers.
    
    Returns:
    
    This instance, if no change, or newly constructed instance
    
    Throws:
    
    JsonMappingException - If there are issues with contextualization
    
    Since:
    
    2.12
  - getValueClass
```
public Class<?> getValueClass()
```
    Accessor for raw (type-erased) type of instances to create.
    NOTE: since this method has not existed since beginning of Jackson 2.0 series, default implementation will just return Object.class; implementations are expected to override it with real value.
    
    Since:
    
    2.8
  - getValueTypeDesc
```
public String getValueTypeDesc()
```
    Method that returns description of the value type this instantiator handles. Used for error messages, diagnostics.
  - canInstantiate
```
public boolean canInstantiate()
```
    Method that will return true if any of canCreateXxx method returns true: that is, if there is any way that an instance could be created.
  - canCreateFromString
```
public boolean canCreateFromString()
```
    Method that can be called to check whether a String-based creator is available for this instantiator.
    NOTE: does NOT include possible case of fallbacks, or coercion; only considers explicit creator.
  - canCreateFromInt
```
public boolean canCreateFromInt()
```
    Method that can be called to check whether an integer (int, Integer) based creator is available to use (to call createFromInt(com.fasterxml.jackson.databind.DeserializationContext, int)).
  - canCreateFromLong
```
public boolean canCreateFromLong()
```
    Method that can be called to check whether a long (long, Long) based creator is available to use (to call createFromLong(com.fasterxml.jackson.databind.DeserializationContext, long)).
  - canCreateFromBigInteger
```
public boolean canCreateFromBigInteger()
```
    Method that can be called to check whether a BigInteger based creator is available to use (to call createFromBigInteger(com.fasterxml.jackson.databind.DeserializationContext, java.math.BigInteger)). +
  - canCreateFromDouble
```
public boolean canCreateFromDouble()
```
    Method that can be called to check whether a double (double / Double) based creator is available to use (to call createFromDouble(com.fasterxml.jackson.databind.DeserializationContext, double)).
  - canCreateFromBigDecimal
```
public boolean canCreateFromBigDecimal()
```
    Method that can be called to check whether a BigDecimal based creator is available to use (to call createFromBigDecimal(com.fasterxml.jackson.databind.DeserializationContext, java.math.BigDecimal)).
  - canCreateFromBoolean
```
public boolean canCreateFromBoolean()
```
    Method that can be called to check whether a double (boolean / Boolean) based creator is available to use (to call createFromDouble(com.fasterxml.jackson.databind.DeserializationContext, double)).
  - canCreateUsingDefault
```
public boolean canCreateUsingDefault()
```
    Method that can be called to check whether a default creator (constructor, or no-arg static factory method) is available for this instantiator
  - canCreateUsingDelegate
```
public boolean canCreateUsingDelegate()
```
    Method that can be called to check whether a delegate-based creator (single-arg constructor or factory method) is available for this instantiator
  - canCreateUsingArrayDelegate
```
public boolean canCreateUsingArrayDelegate()
```
    Method that can be called to check whether a array-delegate-based creator (single-arg constructor or factory method) is available for this instantiator
    
    Since:
    
    2.7
  - canCreateFromObjectWith
```
public boolean canCreateFromObjectWith()
```
    Method that can be called to check whether a property-based creator (argument-taking constructor or factory method) is available to instantiate values from JSON Object
  - getFromObjectArguments
```
public SettableBeanProperty[] getFromObjectArguments(DeserializationConfig config)
```
    Method called to determine types of instantiation arguments to use when creating instances with creator arguments (when canCreateFromObjectWith() returns true). These arguments are bound from JSON, using specified property types to locate deserializers.
    NOTE: all properties will be of type CreatorProperty.
  - getDelegateType
```
public JavaType getDelegateType(DeserializationConfig config)
```
    Method that can be used to determine what is the type of delegate type to use, if any; if no delegates are used, will return null. If non-null type is returned, deserializer will bind JSON into specified type (using standard deserializer for that type), and pass that to instantiator.
  - getArrayDelegateType
```
public JavaType getArrayDelegateType(DeserializationConfig config)
```
    Method that can be used to determine what is the type of array delegate type to use, if any; if no delegates are used, will return null. If non-null type is returned, deserializer will bind JSON into specified type (using standard deserializer for that type), and pass that to instantiator.
    
    Since:
    
    2.7
  - createUsingDefault
```
public Object createUsingDefault(DeserializationContext ctxt)
                          throws IOException
```
    Method called to create value instance from a JSON value when no data needs to passed to creator (constructor, factory method); typically this will call the default constructor of the value object. It will only be used if more specific creator methods are not applicable; hence "default".
    This method is called if getFromObjectArguments(com.fasterxml.jackson.databind.DeserializationConfig) returns null or empty List.
    
    Throws:
    
    IOException
  - createFromObjectWith
```
public Object createFromObjectWith(DeserializationContext ctxt,
                                   Object[] args)
                            throws IOException
```
    Method called to create value instance from JSON Object when instantiation arguments are passed; this is done, for example when passing information specified with "Creator" annotations.
    This method is called if getFromObjectArguments(com.fasterxml.jackson.databind.DeserializationConfig) returns a non-empty List of arguments.
    
    Throws:
    
    IOException
  - createUsingDefaultOrWithoutArguments
```
public Object createUsingDefaultOrWithoutArguments(DeserializationContext ctxt)
                                            throws IOException
```
    Combination of createUsingDefault(com.fasterxml.jackson.databind.DeserializationContext) and createFromObjectWith(DeserializationContext, Object[]) which will call former first, if possible; or latter if possible (with null arguments); and if neither works throw an exception.
    
    Throws:
    
    IOException
    
    Since:
    
    2.15
  - createFromObjectWith
```
public Object createFromObjectWith(DeserializationContext ctxt,
                                   SettableBeanProperty[] props,
                                   PropertyValueBuffer buffer)
                            throws IOException
```
    Method that delegates to createFromObjectWith(DeserializationContext, Object[]) by default, but can be overridden if the application should have customized behavior with respect to missing properties.
    The default implementation of this method uses PropertyValueBuffer.getParameters(SettableBeanProperty[]) to read and validate all properties in bulk, possibly substituting defaults for missing properties or throwing exceptions for missing properties. An overridden implementation of this method could, for example, use PropertyValueBuffer.hasParameter(SettableBeanProperty) and PropertyValueBuffer.getParameter(SettableBeanProperty) to safely read the present properties only, and to have some other behavior for the missing properties.
    
    Throws:
    
    IOException
    
    Since:
    
    2.8
  - createUsingDelegate
```
public Object createUsingDelegate(DeserializationContext ctxt,
                                  Object delegate)
                           throws IOException
```
    Method to called to create value instance from JSON Object using an intermediate "delegate" value to pass to createor method
    
    Throws:
    
    IOException
  - createUsingArrayDelegate
```
public Object createUsingArrayDelegate(DeserializationContext ctxt,
                                       Object delegate)
                                throws IOException
```
    Method to called to create value instance from JSON Array using an intermediate "delegate" value to pass to createor method
    
    Throws:
    
    IOException
  - createFromString
```
public Object createFromString(DeserializationContext ctxt,
                               String value)
                        throws IOException
```
    Throws:
    
    IOException
  - createFromInt
```
public Object createFromInt(DeserializationContext ctxt,
                            int value)
                     throws IOException
```
    Throws:
    
    IOException
  - createFromLong
```
public Object createFromLong(DeserializationContext ctxt,
                             long value)
                      throws IOException
```
    Throws:
    
    IOException
  - createFromBigInteger
```
public Object createFromBigInteger(DeserializationContext ctxt,
                                   BigInteger value)
                            throws IOException
```
    Throws:
    
    IOException
  - createFromDouble
```
public Object createFromDouble(DeserializationContext ctxt,
                               double value)
                        throws IOException
```
    Throws:
    
    IOException
  - createFromBigDecimal
```
public Object createFromBigDecimal(DeserializationContext ctxt,
                                   BigDecimal value)
                            throws IOException
```
    Throws:
    
    IOException
  - createFromBoolean
```
public Object createFromBoolean(DeserializationContext ctxt,
                                boolean value)
                         throws IOException
```
    Throws:
    
    IOException
  - getDefaultCreator
```
public AnnotatedWithParams getDefaultCreator()
```
    Method that can be called to try to access member (constructor, static factory method) that is used as the "default creator" (creator that is called without arguments; typically default [zero-argument] constructor of the type). Note that implementations not required to return actual object they use (or, they may use some other instantiation) method. That is, even if canCreateUsingDefault() returns true, this method may return null .
  - getDelegateCreator
```
public AnnotatedWithParams getDelegateCreator()
```
    Method that can be called to try to access member (constructor, static factory method) that is used as the "delegate creator". Note that implementations not required to return actual object they use (or, they may use some other instantiation) method. That is, even if canCreateUsingDelegate() returns true, this method may return null .
  - getArrayDelegateCreator
```
public AnnotatedWithParams getArrayDelegateCreator()
```
    Method that can be called to try to access member (constructor, static factory method) that is used as the "array delegate creator". Note that implementations not required to return actual object they use (or, they may use some other instantiation) method. That is, even if canCreateUsingArrayDelegate() returns true, this method may return null .
  - getWithArgsCreator
```
public AnnotatedWithParams getWithArgsCreator()
```
    Method that can be called to try to access member (constructor, static factory method) that is used as the "non-default creator" (constructor or factory method that takes one or more arguments). Note that implementations not required to return actual object they use (or, they may use some other instantiation) method. That is, even if canCreateFromObjectWith() returns true, this method may return null .
  - _createFromStringFallbacks
```
@Deprecated
protected Object _createFromStringFallbacks(DeserializationContext ctxt,
                                                        String value)
                                                 throws IOException
```
    Deprecated. Since 2.12 should not handle coercions here
    
    Throws:
    
    IOException
    
    Since:
    
    2.4 (demoted from StdValueInstantiator)

Class ValueInstantiator

Nested Class Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

ValueInstantiator

Method Detail

createContextual

getValueClass

getValueTypeDesc

canInstantiate

canCreateFromString

canCreateFromInt

canCreateFromLong

canCreateFromBigInteger

canCreateFromDouble

canCreateFromBigDecimal

canCreateFromBoolean

canCreateUsingDefault

canCreateUsingDelegate

canCreateUsingArrayDelegate

canCreateFromObjectWith

getFromObjectArguments

getDelegateType

getArrayDelegateType

createUsingDefault

createFromObjectWith

createUsingDefaultOrWithoutArguments

createFromObjectWith

createUsingDelegate

createUsingArrayDelegate

createFromString

createFromInt

createFromLong

createFromBigInteger

createFromDouble

createFromBigDecimal

createFromBoolean

getDefaultCreator

getDelegateCreator

getArrayDelegateCreator

getWithArgsCreator

_createFromStringFallbacks