I'm a little confused by a warning that my Eclipse IDE is currently writing next to every expression where types are autoboxed or autounboxed:
The expression of type x is boxed into X
The expression of type X is unboxed into x
Is this a warning I should react on? I thought autoboxing was a Java language feature - but now I seem to get warnings everytime this feature is used.
I don't think Eclipse does this by default (mine does not), but you can turn it on or off using Preferences > Java > Compiler > Errors/Warnings > Potential programming problems > Boxing and Unboxing Conversions.
It should be "Ignore" unless you really want to know about this.
来源：https://stackoverflow.com/questions/5039105/the-expression-of-type-x-is-boxed-into-x