java - Default constructor vs. inline field initialization -

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what's difference between default constructor , initializing object's fields directly?

what reasons there prefer 1 of following examples on other?

example 1

public class foo {     private int x = 5;     private string[] y = new string[10]; }

example 2

public class foo {     private int x;     private string[] y;      public foo()     {         x = 5;         y = new string[10];     } }

initialisers executed before constructor bodies. (which has implications if have both initialisers , constructors, constructor code executes second , overrides initialised value)

initialisers when need same initial value (like in example, array of given size, or integer of specific value), can work in favour or against you:

if have many constructors initialise variables differently (i.e. different values), initialisers useless because changes overridden, , wasteful.

on other hand, if have many constructors initialise same value can save lines of code (and make code more maintainable) keeping initialisation in 1 place.

like michael said, there's matter of taste involved - might keep code in 1 place. although if have many constructors code isn't in 1 place in case, favour initialisers.


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