java: static and nonstatc function calling approach -


i have class:

public class c1{   public int v=10;   public int myfunction1(){        // code   } }

to call myfunction1() use:

c1 ob = new c1(); ob.myfunction1(); ob.v;

same thing `static':

public class c1{   public static int v=10;   public static int myfunction1(){        // code   } }

to call myfunction1() use:

c1.myfunction1(); c1.v;

so question difference between these 2 approach. when use static approach? technical advantage , disadvantage of both?

the difference best illustrated if change example somewhat:

public class c1{     private final int v;      public c1(final int v) {         this.v = v;     }      public int getv(){        return v;     } }

in case when create c1 give internal state - i.e. v. can do

final c1 firstc1 = new c1(10); final c1 secondc1 = new c1(20);

you cannot static methods bound class instance , not object instance - hence change in state seen all method calls.

generally, in oo design, static best avoided. has places, it's used utility classes , constants (although in java enums better constants).


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