Lazy Proxies

Lazy proxies refers to only loading data elements when they are actually required. Lazy Proxies is one of two "lazy" OO concepts that derive from the Functional Programming idea of "lazy evaluation", the other being LazyInstantiationPattern. Lazy proxies is a capability that can be implemented in database mapping (also called Object Relational Mapping) software.

• Described in Java Skyline: Design News (week of July 15), http://www.javaskyline.com/designnews.jsp
• Martin Fowler's discourse on Lazy Loads and Lazy Proxies in database mapping, http://www.martinfowler.com/isa/virtualProxy.html and
• Thomas Mahler's OJB O/R Mapping software, ObjectRelationalBridge, http://db.apache.org/ojb, which implements Lazy Proxies. OJB has been used recently with JBoss and with Oracle.

See also:

• RefactoringWithRelationalDatabases.
• Database Object Relational Mapping Tools, http://www.javaskyline.com/database.html
• Lazy Instantiation, http://www.javaworld.com/javaworld/javatips/jw-javatip67.html by Philip Bishop and Nigel Warren

-- RichKatz

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CategoryFunctionalProgramming CategoryLazyPattern