Difference of Type casting in Android and Java -


i m trying write tool testing android apps.

in middle of path, encountered problem in type casting. know type casting parent class 1 of child classes not correct.but don't know in android apps, why can have such thing that?

to clear, have written test java program in eclipse. in "view" class parent , "toolbar" class child extends it.

the problem emerges when try type casting view toolbar.both lines of program make exceptions can see below. how can fix such exception?

    package main;  import a.view; import b.toolbar;  public class aaa {    public static void main(string[] args) {     // todo auto-generated method stub     double x = 2;     toolbar t= (toolbar) new view();      toolbar xs = (toolbar) new object();   }  }

the exception is: exception in thread "main" java.lang.classcastexception: java.lang.object cannot cast b.toolbar @ main.aaa.main(aaa.java:13)


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