Why are some constants public and other private in an Android library code -

problem

why constants under public modifier while other private? under public can called applications use library? if so, how call constant app, this: certainlibraryclass.activityresultcode.code_a?

code

public class certainlibraryclass {     public class activityresultcode {     public static final int code_a = 0x02;     public static final int code_b = 0x03;     public static final int code_c = 0x04;     }     public class versioncode {         private static final int version_major = 1;         private static final int version_minor1 = 0;         private static final int version_minor2 = 2;     } // .... } 

why constants under public modifier?

ans: other classes can access e.g.result_ok,success.

why constants under private modifier?

ans:so class can access it

e.g. consider calling getid() libarary function class

public class certainlibraryclass { private static int id=0;  public static int getid() { return id+1; } 

here not accessing id field directly ,instead calling getid() function returns id, means id variable internally used certainlibraryclass class