Which of the following methods returns the number of rows affected by the DML operation?
- getRowCount()
- getUpdateCount()
- getResultCount()
- getAffectedRowCount()
The correct method to retrieve the number of rows affected by a DML (Data Manipulation Language) operation in JDBC is getUpdateCount(). This method returns an integer representing the number of rows affected by the last executed query or update statement. Options a, c, and d are not standard JDBC methods for retrieving the row count affected by DML operations.
The ______ interface is implemented by classes that want to handle events of a specific type, with event type and event source defined as generic parameters.
- ActionListener
- EventHandler
- EventListener
- EventSource
In Java, the EventHandler interface is used for handling events of a specific type. It allows you to define the event type and event source as generic parameters, making it a versatile choice for handling various types of events in a type-safe manner. Classes that implement this interface can respond to events of the specified type.
Which method converts a given string to a sequence of characters?
- charAt()
- split()
- toCharArray()
- toString()
The toCharArray() method in Java's String class converts a given string into an array of characters, providing a sequence of characters. The other methods do not perform this specific task.
A ________ is used to create a client socket in Java.
- DatagramSocket
- InetAddress
- ServerSocket
- Socket
In Java, to create a client socket, you use the Socket class. It allows you to establish a connection to a remote server and communicate with it. The other options represent different types of socket classes in Java but are not used for creating client sockets.
The ________ method of DatagramSocket class is used to send a packet to a server.
- send()
- sendPacket()
- sendToServer()
- transmitPacket()
In Java, the send() method of the DatagramSocket class is used to send a packet to a server. It is a crucial method for working with UDP (User Datagram Protocol) sockets.
What will be the output of the following code snippet: public int add(int a, long b) { return a + b; } and public long add(int a, int b) { return a + b; }?
- Compilation Error: Ambiguous method call.
- Compilation Error: Duplicate method add with the same parameter types.
- Compilation Error: Mismatched return types.
- The code will run without errors, and the output will be the sum of a and b.
The code will result in a compilation error because both methods have the same name and the same parameter types (int and long). Java does not allow you to overload methods based solely on the return type. Overloaded methods must have different parameter lists. Overloading based on return types would lead to ambiguity.
How does the FileWriter class handle character encoding?
- It always uses the system's default character encoding.
- It automatically detects and sets the appropriate character encoding.
- It doesn't support character encoding; it writes bytes as is.
- It prompts the user to choose the encoding when creating an instance.
The FileWriter class in Java uses the system's default character encoding for writing text to a file. It doesn't automatically detect or set character encoding. To specify a different encoding, you should use constructors like FileWriter(String fileName, Charset charset) to explicitly set the encoding.
What will be the initial capacity of a HashSet when no size is defined during its creation?
- 0
- 10
- 16
- It will result in an error
When you create a HashSet in Java without specifying its initial capacity, it defaults to an initial capacity of 16. The capacity dynamically increases as needed when elements are added to the HashSet.
Which modular CSS methodology uses the Block, Element, Modifier structure?
- BEM (Block, Element, Modifier)
- ITCSS (Inverted Triangle CSS)
- OOCSS (Object-Oriented CSS)
- SMACSS (Scalable and Modular Architecture for CSS)
The modular CSS methodology that uses the Block, Element, Modifier structure is BEM, which stands for Block, Element, Modifier. BEM is a naming convention that helps create maintainable and predictable CSS code by organizing styles into blocks, elements, and modifiers.
While using a CSS preprocessor, you notice that the compiled CSS has selectors that are excessively long and specific. What might be a potential cause for this in your source files?
- Overuse of nesting in SASS or LESS
- Lack of CSS optimization tools
- Errors in the preprocessor settings
- Incorrect order of imported stylesheets
Excessively long and specific selectors in compiled CSS are often caused by overusing nesting in preprocessors like SASS or LESS. While nesting can improve code organization, it can also lead to overly specific selectors that increase file size and reduce maintainability.