ComposingAdjunct

java.lang.Object
- com.saxonica.ee.stream.adjunct.StreamingAdjunct
- - com.saxonica.ee.stream.adjunct.ComposingAdjunct

Direct Known Subclasses:

AtomizerAdjunct, CopyOfAdjunct, SnapshotFnStreamer, StringFnStreamer
```
public abstract class ComposingAdjunct
extends StreamingAdjunct
```
Watch factory class for an class that composes items from sequences of events: examples are copy-of(), data(), and string().

Constructor Summary

Constructors
Constructor Description

ComposingAdjunct()

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method	Description
`WatchMaker`	`getWatchMaker(boolean forGrouping)`	Get a WatchMaker, a factory class that creates a Watch to evaluate this expression in streaming mode.
`abstract ItemFeed`	`makeComposingAction(WatchManager watchManager, ItemFeed out, XPathContext context)`	Method that must be implemented in subclasses to supply the feed to which the composed items are sent

Methods inherited from class com.saxonica.ee.stream.adjunct.StreamingAdjunct
computeStreamability, findConsumingArg, getConfiguration, getDefaultFeedMaker, getExpression, getFeedMaker, makeStreamingAdjunct, setConfiguration, setExpression, toStreamingPattern

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

- Constructor Detail
  - ComposingAdjunct
```
public ComposingAdjunct()
```
- Method Detail
  - makeComposingAction
```
public abstract ItemFeed makeComposingAction(WatchManager watchManager,
                                             ItemFeed out,
                                             XPathContext context)
```
    Method that must be implemented in subclasses to supply the feed to which the composed items are sent
    
    Parameters:
    
    watchManager - the watch manager
    
    out - the destination of composed items
    
    context - XPath evaluation context
    
    Returns:
    
    a the relevant ItemFeed
  - getWatchMaker
```
public WatchMaker getWatchMaker(boolean forGrouping)
                         throws XPathException
```
    Description copied from class: StreamingAdjunct
    
    Get a WatchMaker, a factory class that creates a Watch to evaluate this expression in streaming mode. This method will only be called if the getImplementationMethod() method of the expression includes the value Expression.WATCH_METHOD
    
    Overrides:
    
    getWatchMaker in class StreamingAdjunct
    
    Parameters:
    
    forGrouping - true if the selected items are being grouped
    
    Returns:
    
    a Watchmaker to evaluate the expression, or null if it is not streamable with respect to the specificed argument.
    
    Throws:
    
    XPathException - in the event of a failure