Here is a new chatbot application implementation.
Below is the partial code of the application, in particular, the AboutCommand interface, which must return the text Copyright (c) 2023, http://mycompany.com.
Which statement is correct? Choose one.
A) The code is compilable and works as expected.
B) The code is not compilable. To fix the code, the final modifier on the variable HOME_PAGE must be removed.
C) The code is incorrect. To fix it, modify lines 2 and 3 like this:
url.substring(0, url.lastIndexOf("/")); // line 2
url.substring(0, url.lastIndexOf("/")); // line 3
D) The code is incorrect. To fix it, modify lines 2 and 3 like this:
var url = this.url.substring(0, this.url.lastIndexOf("/")); // line 2
url = this.url.substring(0, this.url.lastIndexOf("/")); // line 3
E) The code is incorrect. To fix it, modify lines 2 and 3 like this:
var url = this.url.substring(0, this.url.lastIndexOf("/")); // line 2
url = url.substring(0, url.lastIndexOf("/")); // line 3
#java #certificationquestion #ocp
Answer:
To begin with, option A is incorrect.
The first call of the execute() is ok.
But it modifies the instance variable.
Therefore, a second call will return only Copyright (c) 2023, http:.
A third call will throw java.lang.StringIndexOutOfBoundsException.
Option B is incorrect.
We do not reassign the HOME_PAGE constant, so we don't care about the final modifier.
Option C is also incorrect.
It avoids reassigning the url field, which seems like a step forward.
However, strings are immutable, so line 4 will return the initial unchanged value.
Line 2 will create a new string containing the text http://mycompany.com/botapp, but that string is immediately abandoned because its reference is not stored anywhere.
Line 3 simply repeats the process, and the new string is abandoned again.
Therefore, the result will be Copyright (c) 2023,
http://mycompany.com/botapp/index.html.
Option D is incorrect.
It introduces a new local variable, String url.
This new string is stored in the local variable called url.
However, line 3 simply repeats the behavior of line 2, because it reads its starting value from the field called url, not the value created by line 2.
Consequently, this version produces the message Copyright (c) 2023, http://mycompany.com/botapp.