Computer Science Java Exam 2025
Questions and Answers
keywords - ANSWER✔✔-class, while and if are....
primitive types - ANSWER✔✔-which are simple values stored directly in the memory
location
reference types - ANSWER✔✔-which store addresses of objects stored somewhere else
in memory
static - ANSWER✔✔-methods not associated with any object
instance - ANSWER✔✔-methods are part of objects and can only be called through an
object
What are the two general ways of accessing a Java array? - ANSWER✔✔-direct access
and sequential access
direct access - ANSWER✔✔-accessing an arbitrary location
sequential access - ANSWER✔✔-going through the entire array
, compiler/syntax errors - ANSWER✔✔-prevent program from being compiled properly,
forgetting semicolon or braces
logic errors - ANSWER✔✔-are problems with what the code actually does, like
forgetting braces around else, so the code doesn't know what to do with else
Data hiding - ANSWER✔✔-when an object hides its internal data from code outside the
class that the object
//is an instance of. Only the class can access its own methods. Make fields private and
methods public
data abstraction - ANSWER✔✔-using a class without knowing its implementation
Details
differences between array and arraylist - ANSWER✔✔-- Array is a fixed length data
structure
- arraylist- You can not change length of Array once created in Java but ArrayList re-
size itself when gets full depending upon capacity and load factor.
Questions and Answers
keywords - ANSWER✔✔-class, while and if are....
primitive types - ANSWER✔✔-which are simple values stored directly in the memory
location
reference types - ANSWER✔✔-which store addresses of objects stored somewhere else
in memory
static - ANSWER✔✔-methods not associated with any object
instance - ANSWER✔✔-methods are part of objects and can only be called through an
object
What are the two general ways of accessing a Java array? - ANSWER✔✔-direct access
and sequential access
direct access - ANSWER✔✔-accessing an arbitrary location
sequential access - ANSWER✔✔-going through the entire array
, compiler/syntax errors - ANSWER✔✔-prevent program from being compiled properly,
forgetting semicolon or braces
logic errors - ANSWER✔✔-are problems with what the code actually does, like
forgetting braces around else, so the code doesn't know what to do with else
Data hiding - ANSWER✔✔-when an object hides its internal data from code outside the
class that the object
//is an instance of. Only the class can access its own methods. Make fields private and
methods public
data abstraction - ANSWER✔✔-using a class without knowing its implementation
Details
differences between array and arraylist - ANSWER✔✔-- Array is a fixed length data
structure
- arraylist- You can not change length of Array once created in Java but ArrayList re-
size itself when gets full depending upon capacity and load factor.
