PropertyExport (AndHow Core 0.4.2-rc3 API)

All Known Implementing Classes:

PropertyExportImpl, PropertyExportImpl.PropertyExportWrap
```
public interface PropertyExport
```
A set of data for a single Property being exported.
Exports are typically in the form of Key-Value pairs where the key is the Property canonical name and/or 'out' aliases and the value is the real value of the Property.
AndHow#export() returns a Stream of PropertyExport's, one PropertyExport per Property. The ExportCollector has several collectors that transform and collect the stream into Maps or Properties of key-value pairs.
See AndHow#export() for export details and examples.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method and Description
`Exporter.EXPORT_CANONICAL_NAME`	`getCanonicalNameOption()` Option read from the containing `ManualExportAllowed` annotation to determine if the canonical name of the Property should be included.
`Class<?>`	`getContainingClass()` The class directly containing the Property.
`List<String>`	`getExportNames()` The complete list of export names for this property, which may be null, empty or many.
`Exporter.EXPORT_OUT_ALIASES`	`getOutAliasOption()` Option read from the containing `ManualExportAllowed` annotation to determine if 'out' aliases of the Property should be included.
`Property<?>`	`getProperty()` The Property being exported.
`Object`	`getValue()` Fetch the Object value of the Property, e.g., an Integer Property will return an Integer.
`String`	`getValueAsString()` Fetch the value as a String from the Property.
`PropertyExport`	`mapNames(List<String> exportNames)` Intended for using with Java `stream()`s, this method maps this instance to a new one with new export names.
`PropertyExport`	`mapValue(Object value)` Intended for using with Java `stream()`s, this method maps this instance to a new one with a new Object value for the Property, i.e., the 'value' part of a key-value pair.
`PropertyExport`	`mapValueAsString(String value)` Intended for using with Java `stream()`s, this method maps this instance to a new one with a new String value for the Property, i.e., the 'value' part of a key-value pair.

- Method Detail
  - getProperty
```
Property<?> getProperty()
```
    The Property being exported.
    
    Returns:
    
    A Property instance. Not null.
  - getContainingClass
```
Class<?> getContainingClass()
```
    The class directly containing the Property.
    
    Returns:
    
    The containing class. Not null.
  - getCanonicalNameOption
```
Exporter.EXPORT_CANONICAL_NAME getCanonicalNameOption()
```
    Option read from the containing ManualExportAllowed annotation to determine if the canonical name of the Property should be included.
    If included, the canonical name would be included in the list of names returned from getExportNames() and then ultimately as one of the names in the final key-value pairs.
    
    Returns:
    
    An EXPORT_CANONICAL_NAME value. Not null.
  - getOutAliasOption
```
Exporter.EXPORT_OUT_ALIASES getOutAliasOption()
```
    Option read from the containing ManualExportAllowed annotation to determine if 'out' aliases of the Property should be included.
    'Out' aliases are alternate names for a Property for the purpose of export, so generally they are intended to be included.
    
    Returns:
    
    An EXPORT_OUT_ALIASES value. Not null.
  - getExportNames
```
List<String> getExportNames()
```
    The complete list of export names for this property, which may be null, empty or many.
    This method builds and returns the default export name list based on the getCanonicalNameOption() & getOutAliasOption() options, or, if mapNames(List) was used to construct this instance, the list of names specified.
    See AndHow.export(Class[]) for an example that remaps export names.
    
    Returns:
    
    A list of names which may be empty or null.
  - getValue
```
Object getValue()
```
    Fetch the Object value of the Property, e.g., an Integer Property will return an Integer.
    Nominally this is the same as getProperty().getValue(), however, mapValue(Object) can be used to rewrite the value. Take care to map the method that will be used by the collector you have chosen:
    - 'String' collectors call getValueAsString(): use mapValueAsString(String)
    - 'Object' collectors call getValue(): use mapValue(Object)
    Returns:
    
    The value return from the Property getValue() method or a custom value. May be null.
  - getValueAsString
```
String getValueAsString()
```
    Fetch the value as a String from the Property.
    Nominally this is the same as getProperty().getValueAsString(), however, mapValueAsString(String) can be used to rewrite the value. Take care to map the method that will be used by the collector you have chosen:
    - 'String' collectors call getValueAsString(): use mapValueAsString(String)
    - 'Object' collectors call getValue(): use mapValue(Object)
    Implementation note: The nominal implementation of this method should call getProperty().getValueAsString() and not delegate to getValue(), since the type returned by getValue may be overridden and not match the Property type.
    Returns:
    
    The value returned from the Properties getValueAsString method or a custom value. May be null.
  - mapNames
```
PropertyExport mapNames(List<String> exportNames)
```
    Intended for using with Java stream()s, this method maps this instance to a new one with new export names.
    Calling getExportNames() on the new instance returns the new exportNames. Specifying an empty or null list of names will remove this Property from export.
    See AndHow.export(Class[]) for an example that remaps export names.
    
    Parameters:
    
    exportNames - A new list of export names to be used, rather than the default ones.
    
    Returns:
    
    A new instance identical to the original, except it has new names.
  - mapValue
```
PropertyExport mapValue(Object value)
```
    Intended for using with Java stream()s, this method maps this instance to a new one with a new Object value for the Property, i.e., the 'value' part of a key-value pair.
    Calling getValue() on the new instance returns the new value, which may be null.
    This example uses mapValue() to multiply Property values by 2 if they are integers:
```
 Map<String, Object> export =
  AndHow.instance().export(MyClass.class)
   .map(p -> p.mapValue(
     (p.getValue() != null && p.getValue() instanceof Integer)
       ? (Integer)p.getValue() * 2:p.getValue()) )
   .collect(ExportCollector.objectMap());
 
```
    Take care to map the method that will be used by the collector you have chosen:
    - 'String' collectors call getValueAsString(): use mapValueAsString(String)
    - 'Object' collectors call getValue(): use mapValue(Object)
    Parameters:
    
    value - The new value to return for the value of this Property.
    
    Returns:
    
    A new instance identical to the original, except it has a new object value.
  - mapValueAsString
```
PropertyExport mapValueAsString(String value)
```
    Intended for using with Java stream()s, this method maps this instance to a new one with a new String value for the Property, i.e., the 'value' part of a key-value pair.
    Calling getValueAsString() on the new instance returns the new value, which may be null.
    This example uses mapValueAsString() to convert Property values to uppercase:
```
 Map<String, String> export =
  AndHow.instance().export(MyClass.class)
   .map( p -> p.mapValueAsString( p.getValueAsString() != null
     ? p.getValueAsString().toUpperCase():null) )
       .collect(ExportCollector.stringMap());
 
```
    Take care to map the method that will be used by the collector you have chosen:
    - 'String' collectors call getValueAsString(): use mapValueAsString(String)
    - 'Object' collectors call getValue(): use mapValue(Object)
    Parameters:
    
    value - The new value to return for the String value of this Property.
    
    Returns:
    
    A new instance identical to the original, except it has a new String value.

Interface PropertyExport

Method Summary

Method Detail

getProperty

getContainingClass

getCanonicalNameOption

getOutAliasOption

getExportNames

getValue

getValueAsString

mapNames

mapValue

mapValueAsString