java - How can I move functions to a separate file in android studio? -

how can move functions separate file in android studio?

for example, if following code in mainactivity.java:

public class mainactivity extends appcompatactivity {     int var1;    int var2;    int var3    ...    protected void onstart() {       ...       var1 = 102;       var2 = 105;       var3 = add( var1, var2);       ...     }     public void add ( int var1, int var2 ) {       return var1 + var2;    } } 

how can have :

mainactivity.java

public class mainactivity extends appcompatactivity {      int var1;     int var2;     int var3     ...     protected void onstart() {         ...         var1 = 102;         var2 = 105;         var3 = add( var1, var2);         ...      } } 

functions.java

public void add ( int var1, int var2 ) {     return var1 + var2; } 

in "utils.java"

public static string getanydata(){    return "anydata"; } 

called mainactivity (e.g.)

utils.getanydata(); 

but keep in mind utility functions / methods should work that. no oop!

intellij / androidstudio has neat shortcut task.. see here.