Injecting as Property Vs Injecting as Constructor Arguments

[spicymail2009@gmail.com]

HI,

Can any one help me the best way of injecting spring beans.
In my project the pattern will be like
Action<-->Service<-->DAO
<-->Helpers classes

Thanks

[Andreas Senft]

Concerning property vs. constructor injection I suggest the following approach:
If a dependency is required for achieving a valid state of the bean at hand then it should be set in the constructor. If a dependency is optional, it is better assigned via a setter.

Hope that helps,
Andreas