Package av.meta

This package defines Ableverse Meta Facility

See:
Description

Interface Summary

MetaLoader

This interface serves as a bridge between the physical storage for XML files and the MetaBundles loaded from them.

Class Summary

ClassPathLoader	A MetaLoader implementation that loads resources from the java classpath.
CompositeLoader	This class provides an easy way to combine several MetaLoaders.
FileSystemLoader	A MetaLoader implementation that loads resources from the file system.
Meta	This class reflects a fragment inside a particular XML file managed by MetaBundle.
MetaBundle	MetaBundles are used to read internationalized meta information from XML resources.
MetaComposition	This class is the foundation to programmaticly authoring meta resources under a repository.
MetaRepository	MetaRepository is the backbone of Ableverse Meta Facility.

Exception Summary

MetaException	Thrown when meta facility encounts exceptions.
MetaFormatException	Thrown when failed to convert the meta value to required java type.
MetaNotFoundException	Thrown when none node is found inside a MetaBundle or Meta, regarding the searching path of MetaBundle.

Package av.meta Description

This package defines Ableverse Meta Facility

Meta Facility provides means for java classes to retrieve internationalized, runtime administrable meta/configuration information organized in a named hierarchy.

Although a metadata feature(Annotation) has been introduced in J2SE 5.0, values of java annotations are bound to java source code, thus no way to change except recompiling the source code. And annotation metadata can only be associated with class or class members, arbitrary structural meta data is yet still not feasible. While annotation values are looked up backward the inheritance path, it is useful in many cases, but not all that need meta data acquisition. For instance, to configure logging settings. As we all know, loggers are also orginazed in a named hierarchy, when we are using a logger com.my.util.FastMap, we want it is configurable by changing the configuration for com.my.util or com.my or the upwards. For another instance, the resource bundles. The classic java i18n resource bundle mechanism is broadly used nowadays, but if you want to share a set of messages among several components, but they each has their individual message set, things become complex, you'll have to implement a resource bundle hierarchy by yourself. These situations happens to be the problems that Ableverse Message Facility was designed to solve.

See MetaBundle's doc for more information.