PropertyHelper.PropertyEvaluator (Apache Ant API)
Description: declaration: package: org.apache.tools.ant, class: PropertyHelper, interface: PropertyEvaluator

Package org.apache.tools.ant

# Interface PropertyHelper.PropertyEvaluator

All Superinterfaces:
  `PropertyHelper.Delegate`

All Known Implementing Classes:
  `LocalProperties`

Enclosing class:
  `PropertyHelper`

public static interface PropertyHelper.PropertyEvaluator extends PropertyHelper.Delegate
Looks up a property's value based on its name.

Can be used to look up properties in a different storage than the project instance (like local properties for example) or to implement custom "protocols" like Ant's `${toString:refid}` syntax.

Since:
  Ant 1.8.0

- ## Method Summary

  Modifier and Type
  Method
  Description
  `Object`
  `evaluate(String property, PropertyHelper propertyHelper)`
  Evaluate a property.

- ## Method Details

  - ### evaluate

    Object evaluate(String property, PropertyHelper propertyHelper)
    Evaluate a property.
    Parameters:
      `property` - the property's String "identifier".
      `propertyHelper` - the invoking PropertyHelper.
    Returns:
      null if the property name could not be found, an instance of `NullReturn` to indicate a property with a name that can be matched but a value of `null` and the property's value otherwise.