org.javamoney.moneta.internal.loader

Class LoadableResource

java.lang.Object

org.javamoney.moneta.internal.loader.LoadableResource

public class LoadableResource
extends Object

This class represent a resource that automatically is reloaded, if needed. To create this instance use: LoadableResourceBuilder

Author:

Anatole Tresch

Method Summary

Modifier and Type	Method and Description
protected void	clearCache() This method is called when the cached data should be removed, e.g. after an explicit fallback reload, or a clear operation.
int	getAccessCount() Get the number of successful accesses.
byte[]	getData() Get the resource data.
protected byte[]	getData(boolean loadIfNeeded)
InputStream	getDataStream() Get the resource data as input stream.
URI	getFallbackResource() Return the fallback location.
long	getLastLoaded() Get the timestamp of the last succesful load.
int	getLoadCount() Get the number of active loads of this resource (InputStream).
Map<String,String>	getProperties() Get the configuration properties of this resource.
List<URI>	getRemoteResources() Get the remote locations.
String	getResourceId() Get the resourceId.
LoaderService.UpdatePolicy	getUpdatePolicy() Get the UpdatePolicy of this resource.
boolean	load() Loads the resource, first from the remote resources, if that fails from the fallback location.
protected boolean	load(URI itemToLoad, boolean fallbackLoad) Tries to load the data from the given location.
boolean	loadFallback() Try to load the resource from the fallback resources.
boolean	loadRemote() Try to load the resource from the remote locations.
protected boolean	readCache() This method is called when the data should be loaded from the cache.
boolean	resetToFallback() Explicitly override the resource wih the fallback context and resets the load counter.
protected void	setData(byte[] bytes)
String	toString()
void	unload()
protected void	writeCache() This method is called after data could be successfully loaded from a non fallback resource.

Methods inherited from class java.lang.Object

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

Method Detail

getUpdatePolicy

public LoaderService.UpdatePolicy getUpdatePolicy()

Get the UpdatePolicy of this resource.

Returns:

the UpdatePolicy of this resource, never null.

getProperties

public Map<String,String> getProperties()

Get the configuration properties of this resource.

Returns:

the configuration properties of this resource, never null.

load

public boolean load()

Loads the resource, first from the remote resources, if that fails from the fallback location.

Returns:

true, if load succeeded.

getResourceId

public final String getResourceId()

Get the resourceId.

Returns:

the resourceId

getRemoteResources

public final List<URI> getRemoteResources()

Get the remote locations.

Returns:

the remote locations, maybe empty.

getFallbackResource

public final URI getFallbackResource()

Return the fallback location.

Returns:

the fallback location, or null.

getLoadCount

public final int getLoadCount()

Get the number of active loads of this resource (InputStream).

Returns:

the number of successful loads.

getAccessCount

public final int getAccessCount()

Get the number of successful accesses.

Returns:

the number of successful accesses.

getDataStream

public InputStream getDataStream()

Get the resource data as input stream.

Returns:

the input stream.

getLastLoaded

public final long getLastLoaded()

Get the timestamp of the last succesful load.

Returns:

the lastLoaded

loadRemote

public boolean loadRemote()

Try to load the resource from the remote locations.

Returns:

true, on success.

loadFallback

public boolean loadFallback()

Try to load the resource from the fallback resources. This will override any remote data already loaded, and also will clear the cached data.

Returns:

true, on success.

clearCache

protected void clearCache()

This method is called when the cached data should be removed, e.g. after an explicit fallback reload, or a clear operation.

readCache

protected boolean readCache()

This method is called when the data should be loaded from the cache. This method abstracts the effective caching mechanism implemented. By default it tries to read a file from the current user's home directory. If the data could be read, #setData(byte[]) should be called to apply the data read.

Returns:

true, if data could be read and applied from the cache sucdcessfully.

writeCache

protected void writeCache()
                   throws IOException

This method is called after data could be successfully loaded from a non fallback resource. This method by default writes an file containing the data into the user's local home directory, so subsequent or later calls, even after a VM restart, should be able to recover this information.

Throws:

IOException

load

protected boolean load(URI itemToLoad,
                       boolean fallbackLoad)

Tries to load the data from the given location. The location hereby can be a remote location or a local location. Also it can be an URL pointing to a current dataset, or an url directing to fallback resources, e.g. within the cuzrrent classpath.

Parameters:

itemToLoad - the target URL

fallbackLoad - true, for a fallback URL.

getData

public final byte[] getData()

Get the resource data. This will trigger a full load, if the resource is not loaded, e.g. for LAZY resources.

Returns:

the data to load.

getData

protected byte[] getData(boolean loadIfNeeded)

setData

protected final void setData(byte[] bytes)

unload

public void unload()

resetToFallback

public boolean resetToFallback()

Explicitly override the resource wih the fallback context and resets the load counter.

Returns:

true on success.

Throws:

IOException

toString

public String toString()

Overrides:

toString in class Object