org.jasig.services.persondir.support.xml
Class CachingJaxbLoaderImpl<T>

java.lang.Object
  org.jasig.services.persondir.support.xml.CachingJaxbLoaderImpl<T>

All Implemented Interfaces:

CachingJaxbLoader<T>

public class CachingJaxbLoaderImpl<T>
extends Object
implements CachingJaxbLoader<T>

Base logic for loading unmarshalling an XML document via JAXB and only reloading the cached object model when needed. The class attempts to monitor the lastModified date of the Resource to determine when to reload. If that fails the resource is reloaded periodically as specified by the setNoLastModifiedReloadPeriod(long) property. The class determines the return type and the base package to use for the JAXBContext.newInstance(String) call via the loadedType parameter provided to the constructor.

Version:

$Revision$

Author:

Eric Dalquist

Nested Class Summary

Nested classes/interfaces inherited from interface org.jasig.services.persondir.support.xml.CachingJaxbLoader

CachingJaxbLoader.UnmarshallingCallback<T>

Field Summary

protected long	lastModifiedTime
protected Class<T>	loadedType
protected org.springframework.core.io.Resource	mappedXmlResource
protected long	noLastModifiedReloadPeriod
protected T	unmarshalledObject

Constructor Summary

CachingJaxbLoaderImpl(Class<T> loadedType)

Method Summary

protected JAXBContext	getJAXBContext()
protected Long	getLastModified()
org.springframework.core.io.Resource	getMappedXmlResource()
long	getNoLastModifiedReloadPeriod()
T	getUnmarshalledObject() Loads and unmarshalls the XML as needed, returning the unmarshalled object
T	getUnmarshalledObject(CachingJaxbLoader.UnmarshallingCallback<T> callback)
protected Unmarshaller	getUnmarshaller(JAXBContext jaxbContext)
protected InputStream	getXmlInputStream()
protected boolean	isCacheValid(Long lastModified) Determines if the cached unmarshalled object is still valid
void	setMappedXmlResource(org.springframework.core.io.Resource mappedXmlResource) The XML resource to load.
void	setNoLastModifiedReloadPeriod(long noLastModifiedReloadPeriod) Period between reloads if last-modified of the Resource cannot be determined
protected T	unmarshal(InputStream xmlInputStream, Unmarshaller unmarshaller)

Methods inherited from class java.lang.Object

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

Field Detail

loadedType

protected final Class<T> loadedType

noLastModifiedReloadPeriod

protected long noLastModifiedReloadPeriod

mappedXmlResource

protected org.springframework.core.io.Resource mappedXmlResource

unmarshalledObject

protected T unmarshalledObject

lastModifiedTime

protected long lastModifiedTime

Constructor Detail

CachingJaxbLoaderImpl

public CachingJaxbLoaderImpl(Class<T> loadedType)

Method Detail

getNoLastModifiedReloadPeriod

public long getNoLastModifiedReloadPeriod()

setNoLastModifiedReloadPeriod

public void setNoLastModifiedReloadPeriod(long noLastModifiedReloadPeriod)

Period between reloads if last-modified of the Resource cannot be determined

getMappedXmlResource

public org.springframework.core.io.Resource getMappedXmlResource()

setMappedXmlResource

public void setMappedXmlResource(org.springframework.core.io.Resource mappedXmlResource)

The XML resource to load.

getUnmarshalledObject

public T getUnmarshalledObject()

Description copied from interface: CachingJaxbLoader

Loads and unmarshalls the XML as needed, returning the unmarshalled object

Specified by:

getUnmarshalledObject in interface CachingJaxbLoader<T>

getUnmarshalledObject

public T getUnmarshalledObject(CachingJaxbLoader.UnmarshallingCallback<T> callback)

Specified by:

getUnmarshalledObject in interface CachingJaxbLoader<T>

Parameters:

callback - Callback that will be executed after the object is unmarshalled (if it needs to be) but before it is returned

See Also:

CachingJaxbLoader.getUnmarshalledObject()

getLastModified

protected Long getLastModified()

Returns:

The last modified date for the XML file, null if it cannot be determined

isCacheValid

protected boolean isCacheValid(Long lastModified)

Determines if the cached unmarshalled object is still valid

Parameters:

lastModified - last modified timestamp of the resource, null if not known.

Returns:

true if the cached object should be used

getXmlInputStream

protected InputStream getXmlInputStream()

Returns:

The InputStream to read the XML file from

getJAXBContext

protected JAXBContext getJAXBContext()

Returns:

The JAXB context to parse the XML resource with

getUnmarshaller

protected Unmarshaller getUnmarshaller(JAXBContext jaxbContext)

Parameters:

jaxbContext - The context to get an unmarshaller for

Returns:

An unmarshaller to use to generate object from the XML

unmarshal

protected T unmarshal(InputStream xmlInputStream,
                      Unmarshaller unmarshaller)

Parameters:

xmlInputStream - InputStream to read the XML from

unmarshaller - Unmarshaller to generate the object from the XML with

Returns:

An unmarshalled object model of the XML