MapperImpl (ConfigMe 1.0.1 API)

java.lang.Object
- ch.jalu.configme.beanmapper.MapperImpl

All Implemented Interfaces:

Mapper

Direct Known Subclasses:

DefaultMapper
```
public class MapperImpl
extends Object
implements Mapper
```
Implementation of Mapper.
Maps a section of a property resource to the provided JavaBean class. The mapping is based on the bean's properties, whose names must correspond with the names in the property resource. For example, if a JavaBean class has a property length and should be mapped from the property resource's value at path definition, the mapper will look up definition.length to get the value of the JavaBean property.
Classes must be JavaBeans. These are simple classes with private fields, accompanied with getters and setters. The mapper only considers properties which have both a getter and a setter method. Any Java class without at least one property with both a getter and a setter is not considered as a JavaBean class. Such classes can be supported by implementing a custom LeafValueHandler that performs the conversion from the value coming from the property reader to an object of the class' type.
Recursion: the mapping of values to a JavaBean is performed recursively, i.e. a JavaBean may have other JavaBeans as fields and generic types at any arbitrary "depth."
Collections are only supported if they are explicitly typed, i.e. a field of List<String> is supported but List<?> and List<T extends Number> are not supported. Specifically, you may only declare fields of type List or Set, or a parent type (Collection or Iterable). Fields of type Map are supported also, with similar limitations. Additionally, maps may only have String as key type, but no restrictions are imposed on the value type.
JavaBeans may have optional fields. If the mapper cannot map the property resource value to the corresponding field, it only treats it as a failure if the field's value is null. If the field has a default value assigned to it on initialization, the default value remains and the mapping process continues. A JavaBean field whose value is null signifies a failure and stops the mapping process immediately.

Field Summary

Fields
Modifier and Type Field and Description

static Object RETURN_NULL
Marker object to signal that null is meant to be used as value.

Fields
Modifier and Type	Field and Description
`static Object`	`RETURN_NULL` Marker object to signal that null is meant to be used as value.

Constructor Summary

Constructors
Constructor and Description

MapperImpl()

MapperImpl(BeanDescriptionFactory beanDescriptionFactory, LeafValueHandler leafValueHandler)

Constructors
Constructor and Description
`MapperImpl()`
`MapperImpl(BeanDescriptionFactory beanDescriptionFactory, LeafValueHandler leafValueHandler)`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`Object`	`convertToBean(Object value, TypeInformation beanType)` Creates an object of the given type from the given value.
`protected Object`	`convertValueForType(MappingContext context, Object value)` Main method for converting a value to another type.
`protected Object`	`createBean(MappingContext context, Object value)` Converts the provided value to the requested JavaBeans class if possible.
`protected Object`	`createBeanMatchingType(TypeInformation typeInformation)` Creates an object matching the given type information.
`protected Collection`	`createCollection(MappingContext context, Object value)` Handles the creation of Collection properties.
`protected Collection`	`createCollectionMatchingType(TypeInformation typeInformation)` Creates a Collection of a type which can be assigned to the provided type.
`protected Object`	`createExportValueForSpecialTypes(Object value)` Handles values of types which need special handling (such as Optional).
`protected Map`	`createMap(MappingContext context, Object value)` Handles the creation of a Map property.
`protected Map`	`createMapMatchingType(TypeInformation typeInformation)` Creates a Map of a type which can be assigned to the provided type.
`protected Object`	`createOptional(MappingContext context, Object value)`
`protected MappingContext`	`createRootMappingContext(TypeInformation beanType)`
`protected BeanDescriptionFactory`	`getBeanDescriptionFactory()`
`protected LeafValueHandler`	`getLeafValueHandler()`
`protected Object`	`handleSpecialTypes(MappingContext context, Object value)` Handles special types in the bean mapping process which require special handling.
`Object`	`toExportValue(Object value)` Converts a complex type such as a JavaBean object to simple types suitable for exporting.
`protected static Object`	`unwrapReturnNull(Object o)`

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

Methods inherited from interface ch.jalu.configme.beanmapper.Mapper
convertToBean

- Field Detail
  - RETURN_NULL
```
public static final Object RETURN_NULL
```
    Marker object to signal that null is meant to be used as value.
- Constructor Detail
  - MapperImpl
```
public MapperImpl()
```
  - MapperImpl
```
public MapperImpl(BeanDescriptionFactory beanDescriptionFactory,
                  LeafValueHandler leafValueHandler)
```
- Method Detail
  - getBeanDescriptionFactory
```
protected final BeanDescriptionFactory getBeanDescriptionFactory()
```
  - getLeafValueHandler
```
protected final LeafValueHandler getLeafValueHandler()
```
  - createRootMappingContext
```
protected MappingContext createRootMappingContext(TypeInformation beanType)
```
  - toExportValue
```
public Object toExportValue(Object value)
```
    Description copied from interface: Mapper
    
    Converts a complex type such as a JavaBean object to simple types suitable for exporting. This method typically returns a Map of values, or simple types like String / Number for scalar values. Used in the BeanProperty.toExportValue(T) method.
    
    Specified by:
    
    toExportValue in interface Mapper
    
    Parameters:
    
    value - the object to convert to its export value
    
    Returns:
    
    export value to use
  - createExportValueForSpecialTypes
```
@Nullable
protected Object createExportValueForSpecialTypes(Object value)
```
    Handles values of types which need special handling (such as Optional). Null means the value is not a special type and that the export value should be built differently. Use RETURN_NULL to $ signal that null should be used as the export value of the provided value.
    
    Parameters:
    
    value - the value to convert
    
    Returns:
    
    the export value to use or RETURN_NULL, or null if not applicable
  - unwrapReturnNull
```
protected static Object unwrapReturnNull(Object o)
```
  - convertToBean
```
@Nullable
public Object convertToBean(Object value,
                                      TypeInformation beanType)
```
    Description copied from interface: Mapper
    
    Creates an object of the given type from the given value. Returns null if the conversion is not possible. The value usually stems from a property resource and is a Map of values.
    
    Specified by:
    
    convertToBean in interface Mapper
    
    Parameters:
    
    value - the value to convert (typically a Map)
    
    beanType - the required type
    
    Returns:
    
    object of the given type, or null if not possible
  - convertValueForType
```
@Nullable
protected Object convertValueForType(MappingContext context,
                                               Object value)
```
    Main method for converting a value to another type.
    
    Parameters:
    
    context - the mapping context
    
    value - the value to convert from
    
    Returns:
    
    object whose type matches the one in the mapping context, or null if not applicable
  - handleSpecialTypes
```
@Nullable
protected Object handleSpecialTypes(MappingContext context,
                                              Object value)
```
    Handles special types in the bean mapping process which require special handling.
    
    Parameters:
    
    context - the mapping context
    
    value - the value to convert from
    
    Returns:
    
    object whose type matches the one in the mapping context, or null if not applicable
  - createCollection
```
@Nullable
protected Collection createCollection(MappingContext context,
                                                Object value)
```
    Handles the creation of Collection properties.
    
    Parameters:
    
    context - the mapping context
    
    value - the value to map from
    
    Returns:
    
    Collection property from the value, or null if not applicable
  - createCollectionMatchingType
```
protected Collection createCollectionMatchingType(TypeInformation typeInformation)
```
    Creates a Collection of a type which can be assigned to the provided type.
    
    Parameters:
    
    typeInformation - the required collection type
    
    Returns:
    
    Collection of matching type
  - createMap
```
@Nullable
protected Map createMap(MappingContext context,
                                  Object value)
```
    Handles the creation of a Map property.
    
    Parameters:
    
    context - mapping context
    
    value - value to map from
    
    Returns:
    
    Map property, or null if not applicable
  - createMapMatchingType
```
protected Map createMapMatchingType(TypeInformation typeInformation)
```
    Creates a Map of a type which can be assigned to the provided type.
    
    Parameters:
    
    typeInformation - the required map type
    
    Returns:
    
    Map of matching type
  - createOptional
```
protected Object createOptional(MappingContext context,
                                Object value)
```
  - createBean
```
@Nullable
protected Object createBean(MappingContext context,
                                      Object value)
```
    Converts the provided value to the requested JavaBeans class if possible.
    
    Parameters:
    
    context - mapping context (incl. desired type)
    
    value - the value from the property resource
    
    Returns:
    
    the converted value, or null if not possible
  - createBeanMatchingType
```
protected Object createBeanMatchingType(TypeInformation typeInformation)
```
    Creates an object matching the given type information.
    
    Parameters:
    
    typeInformation - the required type
    
    Returns:
    
    new instance of the given type

Class MapperImpl

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface ch.jalu.configme.beanmapper.Mapper

Field Detail

RETURN_NULL

Constructor Detail

MapperImpl

MapperImpl

Method Detail

getBeanDescriptionFactory

getLeafValueHandler

createRootMappingContext

toExportValue

createExportValueForSpecialTypes

unwrapReturnNull

convertToBean

convertValueForType

handleSpecialTypes

createCollection

createCollectionMatchingType

createMap

createMapMatchingType

createOptional

createBean

createBeanMatchingType