no.sesat.search.site.config
Class AbstractResourceLoader

java.lang.Object
  no.sesat.search.site.config.AbstractResourceLoader

All Implemented Interfaces:

Runnable, BytecodeLoader, DocumentLoader, PropertiesLoader, ResourceLoader

Direct Known Subclasses:

UrlResourceLoader

public abstract class AbstractResourceLoader
extends Object
implements Runnable, DocumentLoader, PropertiesLoader, BytecodeLoader

Utility class to handle loading different types of resources in a background thread. This avoids the problem of having to order loading of applications in the container because of static initialisers using resources from the search-front-config application.
Because the loading is backgrounded it is important to wait until it is finished. This is done by calling abut()

Example usecases:
(1)

 // load custom.properties into props in skin's WEB-INF/classes/
 Site site = ...;
 PropertiesContext context = ...;
 Properties props = new Properties();
 PropertiesLoader loader = context.newPropertiesLoader(site.getSiteContext(), "custom.properties", props);
 loader.abut();
 props.getProperty(...);
 
 (2)
 // create document from my.xml located in skin's WEB-INF/classes/
 Site site = ...;
 DocumentContext context = ...;
 final DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
 factory.setValidating(false);
 final DocumentBuilder builder = factory.newDocumentBuilder();
 loader = context.newDocumentLoader(site.getSiteContext(), "my.xml", builder);
 loader.abut();
 Document doc = loader.getDocument();
 
 (3)
 // read a class file from a jar file located in skin's WEB-INF/lib/
 Site site = ...;
 BytecodeContext context = ...;
 BytecodeLoader loader= context.newBytecodeLoader(site.getSiteContext(),"Example.class", "Example.jar");
 loader.abut()
 byte[] bytes = loader.getBytecode();
 




Version:
  
$Id: AbstractResourceLoader.java 7225 2009-04-09 00:32:20Z ssmiweve $







Field Summary




protected  DocumentBuilder
builder



          DocumentBuilder builder.



protected  Document
document



          Document.



protected  String
jarFileName



          Name of jar to load classes from



protected  Properties
props



          the properties resource holder.


 



Constructor Summary




protected 
AbstractResourceLoader(SiteContext cxt)



          Creates a new instance of AbstractResourceLoader.


 



Method Summary




 void
abut()



          Simple thread.join() wrapper to avoid dealing with InterruptedException.



 byte[]
getBytecode()



          Returns byte code for the class.



protected  SiteContext
getContext()



          Get the SiteContext.



 Document
getDocument()



          get the Document.



protected abstract  InputStream
getInputStreamFor(URL resource)



           



 Properties
getProperties()



          get the properties.



protected  String
getResource()



          Get the resource name/path this class is responsible for retrieving.



protected abstract  URL
getResource(Site site)



           



 void
init(String resource,
     DocumentBuilder builder)



          initialise this resource loader with the resource name/path and the builder used to create the dom.



 void
init(String resource,
     Properties props)



          initialise this resource loader with the resource name/path and the resource it will go into.



 void
initBytecodeLoader(String className,
                   String jarFileName)



          Prepares and loads byte code for a class.



protected  String
readResourceDebug(URL url)



           



 void
run()



           



abstract  boolean
urlExists(URL url)



           


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





Field Detail



props
protected Properties props

the properties resource holder.







builder
protected DocumentBuilder builder

DocumentBuilder builder.







document
protected Document document

Document.







jarFileName
protected String jarFileName

Name of jar to load classes from








Constructor Detail



AbstractResourceLoader
protected AbstractResourceLoader(SiteContext cxt)

Creates a new instance of AbstractResourceLoader.


Parameters:
cxt - the context that we supply us with which site we are dealing with.





Method Detail



urlExists
public abstract boolean urlExists(URL url)











getProperties
public Properties getProperties()

Description copied from interface: PropertiesLoader
get the properties.


Specified by:
getProperties in interface PropertiesLoader



Returns:
the properties.





getDocument
public Document getDocument()

Description copied from interface: DocumentLoader
get the Document.


Specified by:
getDocument in interface DocumentLoader



Returns:
the Document.





getBytecode
public byte[] getBytecode()

Description copied from interface: BytecodeLoader
Returns byte code for the class.


Specified by:
getBytecode in interface BytecodeLoader



Returns:
bytecode.





init
public void init(String resource,
                 Properties props)

Description copied from interface: PropertiesLoader
initialise this resource loader with the resource name/path and the resource it will go into.
 existing properties will not be overwritten.


Specified by:
init in interface PropertiesLoader


Parameters:
resource - the name/path of the resource.
props - the properties that will be used to hold the individual properties.





init
public void init(String resource,
                 DocumentBuilder builder)

Description copied from interface: DocumentLoader
initialise this resource loader with the resource name/path and the builder used to create the dom.


Specified by:
init in interface DocumentLoader


Parameters:
resource - the name/path of the resource.
builder - the document that will be used to hold the xml dom.





initBytecodeLoader
public void initBytecodeLoader(String className,
                               String jarFileName)

Description copied from interface: BytecodeLoader
Prepares and loads byte code for a class.


Specified by:
initBytecodeLoader in interface BytecodeLoader


Parameters:
className - the class to load byte code for.
jarFileName - the jar file to look in.





abut
public void abut()

Description copied from interface: ResourceLoader
Simple thread.join() wrapper to avoid dealing with InterruptedException.
 abut: To touch or end at one end or side; lie adjacent.


Specified by:
abut in interface ResourceLoader








run
public void run()


Specified by:
run in interface Runnable








getResource
protected abstract URL getResource(Site site)











getInputStreamFor
protected abstract InputStream getInputStreamFor(URL resource)











getContext
protected SiteContext getContext()

Get the SiteContext.






Returns:
the SiteContext.





getResource
protected String getResource()

Get the resource name/path this class is responsible for retrieving.






Returns:
the resource name/path.





readResourceDebug
protected String readResourceDebug(URL url)