java - How can I check whether the variable have value or not? -

i new java.might it's simple question,but didn't it.

i have variable, want check whether variable have value or not.for wrote following code.but every time showing false output.

public class stringoperations {     public static void main(string[] args){         boolean b=new boolean("t87778rue");         int = 10;         system.out.println(b.equals(i));     } } 

you're creating boolean object representing false value, because string parameter not "true" (ignoring case).

boolean b=new boolean("t87778rue"); 

next, check whether boolean object representing false equal 10. it's not.

int = 10; system.out.println(b.equals(i)); 

from boolean constructor api documentation:

boolean(string s) allocates boolean object representing value true if string argument not null , equal, ignoring case, string "true".