java - How can I automatically cast an Object reference to the instance type? -


i using jcr api uses method overloading so:

setproperty(string value) setproperty(boolean value) setproperty(integer value) ...

i have collection<object> may contain string, boolean, integer, etc. instances.

i iterate on collection, passing each element correct setproperty implementation instance type. obvious way this:

for (object value : values) {    if (value instanceof string) node.setproperty((string) value);    if (value instanceof boolean) node.setproperty((boolean) value);    if (value instanceof integer) node.setproperty((integer) value);    ... }

now besides being ugly - , deviating oo ideals - solution doesn't scale. while works particular case, become unwieldy number of types grows.

i feel though there must elegant trick or util automatically performing casting operation.

no, there isn't - because you're asking overload resolution, performed @ compile-time, performed @ execution time instead.

options:

  • use reflection find , execute method
  • use visitor pattern emulate double dispatch (this may not appropriate case; i'm not fond of visitor pattern many others are)

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