Engine (CDAP ETL App Template API 6.9.2 API)

```
public interface Engine
```
Engine interface provides access to functions common to all relations used in the tranformation request. E.g. it provides expression factories and engine capabilities.

Method Summary

All Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method and Description
`Set<Capability>`	`getCapabilities()`
`List<ExpressionFactory<?>>`	`getExpressionFactories()`
`default <T> Optional<ExpressionFactory<T>>`	`getExpressionFactory(ExpressionFactoryType<T> type, Capability... neededCapabilities)` Returns expression factory of specified type with required capabilities Example: getExpressionFactory(StringExpressionFactory.SQL)
`default <T> Optional<ExpressionFactory<T>>`	`getExpressionFactory(ExpressionFactoryType<T> type, Collection<Capability> neededCapabilities)` Returns expression factory of specified type with required capabilities Example: getExpressionFactory(StringExpressionFactory.SQL)

- Method Detail
  - getCapabilities
```
Set<Capability> getCapabilities()
```
    Returns:
    
    capabilities provided by the engine and it's expression factories
  - getExpressionFactories
```
List<ExpressionFactory<?>> getExpressionFactories()
```
    Returns:
    
    all expression factories provided by the engine
  - getExpressionFactory
```
default <T> Optional<ExpressionFactory<T>> getExpressionFactory(ExpressionFactoryType<T> type,
                                                                Capability... neededCapabilities)
```
    Returns expression factory of specified type with required capabilities Example: getExpressionFactory(StringExpressionFactory.SQL)
    
    Parameters:
    
    type - expression factory type
    
    neededCapabilities - capabilities that factory should implement
    
    Returns:
    
    a factory or empty optional if engine does not provide such factory
  - getExpressionFactory
```
default <T> Optional<ExpressionFactory<T>> getExpressionFactory(ExpressionFactoryType<T> type,
                                                                Collection<Capability> neededCapabilities)
```
    Returns expression factory of specified type with required capabilities Example: getExpressionFactory(StringExpressionFactory.SQL)
    
    Parameters:
    
    type - expression factory type
    
    neededCapabilities - capabilities that factory should implement
    
    Returns:
    
    a factory or empty optional if engine does not provide such factory

Interface Engine

Method Summary

Method Detail

getCapabilities

getExpressionFactories

getExpressionFactory

getExpressionFactory