What are some appropriate and inappropriate uses of reflection in Java? -

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java's reflection api powerful tool, not particularly object-oriented. situations appropriate (and conversely, inappropriate) use reflection?

in opinion...

appropriate (clean):

  • instantiating root of dynamically-loaded implementation, such applet.
  • use of proxy create proxy or mock implementation (may better @ compile time).
  • implementing interpreters allow unrestricted access java libraries. (note, security perspective interpreted code has effective privileges interpreter - can kind of dangerous.)

appropriate hacks:

  • circumventing java language access controls in third party code absolutely have to.
  • implementing "cross-cutting concern" such persistence.
  • removing static dependencies load classes causing slower start up.

inappropriate:

  • general circumventing java language access controls (includes testing).
  • anything relies upon java language access rights given particular reflection-calling class.
  • anywhere implementing interface work.

generally reflection easier generating source easier creating bytecode.


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