Some months ago I attended a presentation at which Wilfred Springer demonstrated his very cool Preon binary codec library. Defining binary file formats in Preon requires quite a lot of fairly repetitive sets of annotations, and during a chat after the talk Wilfred mentioned (in fact, he blogged about it) how much more convenient it would be if one could just define "shortcuts":

@RequiredEnumProperty(column = "AGENT")

for

@NotNull
@Column(name = "AGENT")
@Enumerated(EnumType.STRING)
 

for instance - and use those instead. Sort-of "macro annotatations" for Java, if you like.
A thought that has presumably also occurred to many frequent users of Hibernate, JAXB or other annotation-heavy frameworks.

Well, it took me rather longer than the couple of days it would probably have taken a developer of Wilfred's skill, but finally @Composite is here! (more...)

Tags: annotation, composite, Java, macro
Filed under Java, Spring | 6 Comments »