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Which exception might be thrown when establishing a connection to a URL in Java?

  • ConnectionException
  • IOException
  • URLException
  • URLIOException
When establishing a connection to a URL in Java, the IOException exception might be thrown. This can happen if there are issues with the network, the URL is invalid, or there are other I/O-related problems during the connection process. The other exception names are not standard in Java.
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In a data processing application, you are looping through a large dataset and performing operations. Midway, an error occurs. How would you ensure that the loop gracefully handles errors and continues processing the remaining data?

  • Use a break statement to exit the loop when an error occurs.
  • Use a throw statement to re-throw the error and stop the loop immediately.
  • Use a try-catch block to catch and handle exceptions.
  • Use an if-else statement to check for errors and skip the current iteration if an error occurs.
To gracefully handle errors during data processing, you would use a try-catch block to catch exceptions, perform error handling, and continue processing the remaining data. The other options either don't handle errors properly or would terminate the loop.
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In Java 12 and later versions, the ________ expression can be used as an alternative to the traditional switch statement, providing a more concise and readable format.

  • for-each
  • lambda
  • switch
  • ternary
In Java 12 and later, you can use the "lambda" expression as an alternative to the traditional switch statement. This feature is also known as "switch expressions." It provides a more concise and readable way to handle multiple cases within a single expression.
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The writeObject method belongs to the ______ class.

  • ObjectOutputStream
  • ObjectSerializer
  • ObjectWriter
  • SerializationWriter
The writeObject method belongs to the ObjectOutputStream class in Java. This method allows you to customize the process of writing an object to an output stream during serialization. It's often used to handle special cases when serializing objects. The other options are not related to writing objects during serialization.
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Which of the following access modifiers allows a member to be accessed from anywhere?

  • default (no modifier)
  • private
  • protected
  • public
In Java, the public access modifier allows a member to be accessed from anywhere, including outside the class, package, and even from different packages. It provides the highest level of accessibility. The other options restrict access to varying degrees.
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You are developing a game and need to compare whether two objects are in the same location, considering that the location is represented using floating-point values. How do you manage the comparison considering the imprecision of floating-point arithmetic?

  • Rely solely on exact comparisons and avoid using floating-point values for location representation.
  • Round the floating-point values to a specified number of decimal places before comparison to eliminate imprecision.
  • Use epsilon values to define a small tolerance level and compare the objects' positions within that tolerance to account for floating-point imprecision.
  • Use integer-based coordinates for location representation to avoid floating-point imprecision altogether.
Floating-point imprecision is a common issue when comparing coordinates in games. To address this, it's best to use epsilon values to define a small tolerance level. This allows for approximate comparisons, accounting for the imprecision inherent in floating-point arithmetic. The other options do not effectively address this issue.
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Which keyword is used to implement an interface in Java?

  • abstract
  • extends
  • implements
  • interface
In Java, the implements keyword is used to implement an interface. When a class implements an interface, it must provide concrete implementations for all the methods declared in that interface. The other options (extends, interface, abstract) are used for different purposes and are not used to implement interfaces.
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What happens when two methods are overloaded with array arguments of the type where one is an array of derived type and another is an array of its base type?

  • It depends on the order in which the methods are defined in the class.
  • The compiler throws an error as it cannot distinguish between the two overloaded methods.
  • The method with the array of the base type is called.
  • The method with the array of the derived type is called.
When two methods are overloaded with array arguments in Java, and one takes an array of a derived type while the other takes an array of its base type, the compiler throws an error. This is because the compiler cannot distinguish between the two methods based on the type of the array, as arrays in Java are covariant.
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The showAndWait() method is used to display a ________ and wait for the user's response.

  • Alert
  • Dialog
  • Notification
  • Popup
In JavaFX, the Alert class is often used to display dialog boxes that require user interaction. The showAndWait() method is used to display an alert dialog and wait for the user's response before proceeding. The other options, Dialog, Popup, and Notification, are not the classes commonly associated with this method.
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Which method is used to read a single character from a character input stream in Java?

  • read()
  • readChar()
  • readCharacter()
  • readLine()
The read() method in Java's character input stream classes is used to read a single character at a time. It returns an integer representing the Unicode code point of the character read. The other options are not valid methods for reading a single character from a character input stream.
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