MetaData Format

Historically there has been several different mechanisms for associating metadata with a component. DNA attempts to learn from past mistakes and make the metadata format extensible to future needs and still simple to use. Thus runtime attribute access is the preferred method for accessing metadata about a component.

MetaClass is the toolkit used to access the metadata about any java class. The MetaClass metadata format maps to a simplified JavaDoc format and thus there is a very simple mapping between the DNA metadata model and MetaClass ClassDescriptor objects. See MetaClass documentation on how to access attributes at runtime.

MetaClass also supports generation of metadata descriptors from annotated Java source files. The annotations supported by DNA components are those specified in the model document.

However some DNA containers may choose to load metadata about components from legacy sources. For example, the Loom container historically supported loading metadata from multiple desciptors BlockInfo ( < classname > .xinfo) and MxInfo ( < classname > .mxinfo). Loom retains support for such components by reading the descriptor files and merging them into a single ClassDescriptor object. See Loom documentation for more details.