/// <summary> Check whether any given resource exists. This is not really
/// a very efficient test and it can and should be overridden in the
/// subclasses extending ResourceLoader.
///
/// </summary>
/// <param name="resourceName">The name of a resource.
/// </param>
/// <returns> true if a resource exists and can be accessed.
/// </returns>
/// <since> 1.6
/// </since>
public virtual bool ResourceExists(string resourceName)
{
System.IO.Stream is_Renamed = null;
try
{
is_Renamed = GetResourceStream(resourceName);
}
catch (ResourceNotFoundException e)
{
if (log.DebugEnabled)
{
log.Debug("Could not load resource '" + resourceName + "' from ResourceLoader " + this.GetType().FullName + ": ", e);
}
}
finally
{
try
{
if (is_Renamed != null)
{
is_Renamed.Close();
}
}
catch (System.Exception e)
{
if (log.ErrorEnabled)
{
string msg = "While closing InputStream for resource '" + resourceName + "' from ResourceLoader " + this.GetType().FullName;
log.Error(msg, e);
throw new VelocityException(msg, e);
}
}
}
return(is_Renamed != null);
}
/// <summary> Initialize the ResourceManager.
///
/// </summary>
/// <param name="rsvc"> The Runtime Services object which is associated with this Resource Manager.
///
/// </param>
/// <throws> Exception </throws>
public virtual void Initialize(IRuntimeServices rsvc)
{
lock (syncOjb)
{
if (isInit)
{
log.Debug("Re-initialization of ResourceLoader attempted and ignored.");
return;
}
ResourceLoader resourceLoader = null;
this.rsvc = rsvc;
log = rsvc.Log;
log.Trace("Default ResourceManager initializing. (" + this.GetType() + ")");
AssembleResourceLoaderInitializers();
for (IEnumerator it = sourceInitializerList.GetEnumerator(); it.MoveNext();)
{
/**
* Resource loader can be loaded either via class name or be passed
* in as an instance.
*/
ExtendedProperties configuration = (ExtendedProperties)it.Current;
string loaderClass = StringUtils.NullTrim(configuration.GetString("class"));
ResourceLoader loaderInstance = (ResourceLoader)configuration["instance"];
if (loaderInstance != null)
{
resourceLoader = loaderInstance;
}
else if (loaderClass != null)
{
resourceLoader = ResourceLoaderFactory.GetLoader(rsvc, loaderClass);
}
else
{
string msg = "Unable to find '" + configuration.GetString(RESOURCE_LOADER_IDENTIFIER) + ".resource.loader.class' specification in configuration." + " This is a critical value. Please adjust configuration.";
log.Error(msg);
throw new System.Exception(msg);
}
resourceLoader.CommonInit(rsvc, configuration);
resourceLoader.Init(configuration);
resourceLoaders.Add(resourceLoader);
}
/*
* now see if this is overridden by configuration
*/
logWhenFound = rsvc.GetBoolean(NVelocity.Runtime.RuntimeConstants.RESOURCE_MANAGER_LOGWHENFOUND, true);
/*
* now, is a global cache specified?
*/
string cacheClassName = rsvc.GetString(RuntimeConstants.RESOURCE_MANAGER_CACHE_CLASS);
object cacheObject = null;
if (!string.IsNullOrEmpty(cacheClassName))
{
try
{
cacheObject = System.Activator.CreateInstance(Type.GetType(cacheClassName.Replace(';', ',')));
}
catch (System.Exception cnfe)
{
string msg = "The specified class for ResourceCache (" + cacheClassName + ") does not exist or is not accessible to the current classloader.";
log.Error(msg, cnfe);
throw cnfe;
}
if (!(cacheObject is IResourceCache))
{
string msg = "The specified resource cache class (" + cacheClassName + ") must implement " + typeof(IResourceCache).FullName;
log.Error(msg);
throw new System.SystemException(msg);
}
}
/*
* if we didn't Get through that, just use the default.
*/
if (cacheObject == null)
{
cacheObject = new ResourceCacheImpl();
}
globalCache = (IResourceCache)cacheObject;
globalCache.Initialize(rsvc);
log.Trace("Default ResourceManager initialization complete.");
}
}
