IValueExtractor (Jadex Active Component Platform 4.0.177 API)

All Known Implementing Classes:

ChainedExtractor, ConstantExtractor, FunctionExtractor, JavaArrayExtractor, JavaMethodExtractor, JavaObjectExtractor, JavaPrefixExtractor, JavaTupleExtractor, MultifieldExtractor, ObjectExtractor, PrefixExtractor, StateExtractor, TupleExtractor
```
public interface IValueExtractor
```
A value extractor is responsible for extracting a certain attribute or object value from a tuple or object.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`AttributeSet`	`getIndirectAttributes()`	Get the set of indirect attribute types.
`AttributeSet`	`getRelevantAttributes()`	Get the set of relevant attribute types.
`java.lang.Object`	`getValue(Tuple left, java.lang.Object right, java.lang.Object prefix, IOAVState state)`	Get the value of an attribute from an object or tuple.
`boolean`	`isAffected(int tupleindex, OAVAttributeType attr)`	Test if a constraint evaluator is affected from a change of a certain attribute.

- Method Detail
  - getValue
```
java.lang.Object getValue(Tuple left,
                          java.lang.Object right,
                          java.lang.Object prefix,
                          IOAVState state)
```
    Get the value of an attribute from an object or tuple.
    
    Parameters:
    
    left - The left input tuple.
    
    right - The right input object.
    
    prefix - The prefix input object (last value from previous extractor in a chain).
    
    state - The working memory.
  - isAffected
```
boolean isAffected(int tupleindex,
                   OAVAttributeType attr)
```
    Test if a constraint evaluator is affected from a change of a certain attribute.
    
    Parameters:
    
    tupleindex - The tuple index (-1 for object).
    
    attr - The attribute.
    
    Returns:
    
    True, if affected.
  - getRelevantAttributes
```
AttributeSet getRelevantAttributes()
```
    Get the set of relevant attribute types.
    
    Returns:
    
    The relevant attribute types.
  - getIndirectAttributes
```
AttributeSet getIndirectAttributes()
```
    Get the set of indirect attribute types. I.e. attributes of objects, which are not part of an object conditions (e.g. for chained extractors)
    
    Returns:
    
    The relevant attribute types.