In a system that processes user commands, you notice that the if-else chain for command processing has become excessively long and difficult to manage. Which refactorization strategy might be most effective?
- Introduce a command pattern
- Split the chain into functions
- Use a nested if-else
- Increase the use of comments
The Command Pattern encapsulates a command request as an object, allowing the parameters to be passed, queued, and executed at a later time. This makes the code modular, maintainable, and ensures decoupling between classes that invoke operations from those that perform operations.
A member function that is used to initialize the class members is known as a _______.
- initializor
- starter
- setter
- constructor
In C++, a constructor is a special member function that is automatically called when an object is instantiated. Its primary purpose is to initialize the object's attributes.
In the context of encapsulation, how does C++ handle data hiding differently from other programming languages?
- By using namespaces exclusively.
- By disallowing external access to data completely.
- Through the use of private and protected access specifiers only.
- By mandatory encapsulation for all classes.
C++ supports data hiding primarily through the use of private and protected access specifiers. Private members are strictly inaccessible from outside the class, while protected members are accessible in derived classes. This mechanism is more flexible compared to some languages that might use other strategies.
Which class is primarily used for performing input operations on files in C++?
- ofstream
- ifstream
- fstream
- filestream
The ifstream class stands for input file stream and is primarily used for performing input operations on files. This means it is used for reading data from files, making it crucial for file handling in C++.
When a pointer is passed to a function, the function receives _______?
- A copy of the actual data
- The memory address
- The function stored in memory
- A blueprint of the data
When a pointer is passed to a function, the function gets a copy of the pointer, which contains the memory address of the data. Therefore, the function can access and modify the original data through this memory address. This is different from passing the actual data, where the function would receive a copy of that data, and any changes wouldn't affect the original data.
Consider a large-scale application where multiple threads often access shared objects concurrently. Which smart pointer can be used to ensure that an object is deleted only when the last pointer to it is out of scope, considering thread safety?
- raw pointer
- shared_ptr
- unique_ptr
- weak_ptr
shared_ptr is thread-safe in terms of its reference counting mechanism, ensuring that the object is safely managed across multiple threads and deleted only when the last pointer to it goes out of scope.
Which of the following stream classes is suitable for both reading and writing operations?
- ifstream
- ofstream
- fstream
- sstream
The "fstream" class in C++ is suitable for both input and output operations. This means you can use it for both reading from and writing to files. In contrast, "ifstream" is specifically for input (reading) and "ofstream" is for output (writing).
Which function is used to get the position of the file pointer in a file?
- getpos()
- seekg()
- tellg()
- seekp()
The "tellg()" function in C++ is used to get the current position of the file pointer in a file when working with input operations. It returns the current position of the reading cursor within the file, which is useful for various file handling tasks.
In C++, if a programmer forgets to deallocate memory using delete, it can result in a _______.
- segmentation fault
- memory leak
- compilation error
- type error
A memory leak in C++ occurs when programmers allocate memory (typically using the new operator) but forget to deallocate it (using the delete operator). This causes the program to consume memory resources continuously, which might lead to system slowdowns or crashes.
Which of the following is a correct file extension for a C++ source file?
- .cpp
- .html
- .java
- .py
C++ source files typically have the extension ".cpp", although other extensions like ".cc" or ".cxx" are also used sometimes.