com.github.wuic.engine

Class NodeEngine

java.lang.Object

com.github.wuic.engine.Engine

com.github.wuic.engine.NodeEngine

All Implemented Interfaces:

Comparable<Engine>

Direct Known Subclasses:

AbstractAggregatorEngine, AbstractCompressorEngine, AbstractConverterEngine, GzipEngine, HtmlInspectorEngine, SpriteInspectorEngine, StaticEngine, TextInspectorEngine

public abstract class NodeEngine
extends Engine

Linkable Engine.

Fundamental design inside WUIC is to use a set of NodeEngine to be executed. They are structured using the chain of responsibility design pattern. Each engine is in charge of the execution of the next engine and could decide not to execute it.

Since:

0.4.4

Version:

1.0

Author:

Guillaume DROUET

Constructor Summary

Constructors

Constructor and Description
NodeEngine()

Method Summary

Methods

Modifier and Type	Method and Description
protected boolean	callNextEngine() Indicates if the next engine should be called by the base class or if this responsibility is delegated to the subclass.
static NodeEngine	chain(NodeEngine... engines) Link the given engines.
NodeEngine	getNext() Returns the next engine previously set with setNext(NodeEngine) method.
abstract List<NutType>	getNutTypes() Gets the all types supported by this engine.
NodeEngine	getPrevious() Returns the previous engine in the chain.
List<ConvertibleNut>	parse(EngineRequest request) Parses the given nuts and returns the result of this operation.
void	setNext(NodeEngine next) The next NodeEngine to be execute din the chain of responsibility.

Methods inherited from class com.github.wuic.engine.Engine

compareTo, getEngineType, internalParse, works

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

NodeEngine

public NodeEngine()

Method Detail

chain

public static NodeEngine chain(NodeEngine... engines)

Link the given engines. They will be linked respecting the order of the implied by their Engine.getEngineType().

If an NodeEngine is already chained to other engines, any engine won't be added as the next engine but to the end of the existing chain.

If two different instances of the same class appear in the chain, then the first one will be replaced by the second one, keeping the original position.

Parameters:

engines - the engines

Returns:

the first engine of the given array

getNutTypes

public abstract List<NutType> getNutTypes()

Gets the all types supported by this engine.

Returns:

the NutType

parse

public List<ConvertibleNut> parse(EngineRequest request)
                           throws WuicException

Parses the given nuts and returns the result of this operation.

Should throw an IllegalArgumentException the files type is not supported by this Engine.

Specified by:

parse in class Engine

Parameters:

request - the request with nuts to parse

Returns:

the parsed nuts

Throws:

WuicException - if any kind of error occurs

setNext

public void setNext(NodeEngine next)

The next NodeEngine to be execute din the chain of responsibility. If it is not set, then this NodeEngine is the last one to be executed.

Parameters:

next - the next Engine

getNext

public NodeEngine getNext()

Returns the next engine previously set with setNext(NodeEngine) method.

Returns:

the next Engine

getPrevious

public NodeEngine getPrevious()

Returns the previous engine in the chain.

Returns:

the previous Engine

callNextEngine

protected boolean callNextEngine()

Indicates if the next engine should be called by the base class or if this responsibility is delegated to the subclass.

Returns:

true if NodeEngine is responsible of calling next engine, false otherwise