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| Section | Weight | Objectives |
|---|---|---|
| Topic 1: Handling Exceptions | 8% | - Create and use custom exceptions, throw, throws - Exception hierarchy, try-catch-finally, multi-catch, try-with-resources |
| Topic 2: Advanced Features and Annotations | 3% | - Generics, type parameters, wildcards, type erasure - Annotations, built-in annotations, custom annotations |
| Topic 3: Modules and Packaging | 5% | - Create and use JAR files, modular and non-modular builds - Module system: module-info.java, exports, requires, provides, uses |
| Topic 4: Functional Programming and Streams | 15% | - Optional class, primitive streams - Lambda expressions, functional interfaces, method references - Stream API: create, intermediate/terminal operations, parallel streams, grouping, partitioning |
| Topic 5: Java I/O and Localization | 5% | - File I/O, NIO.2, streams, readers/writers, serialization - Resource bundles, locale, formatting messages, numbers, dates |
| Topic 6: Handling Date, Time, Text, Numeric and Boolean Values | 12% | - Use Date-Time API: LocalDate, LocalTime, LocalDateTime, Period, Duration, Instant, ZonedDateTime - Use primitives and wrapper classes, evaluate expressions and apply type conversions - Manipulate text, text blocks, String, StringBuilder and StringBuffer |
| Topic 7: Controlling Program Flow | 10% | - Decision constructs: if-else, switch expressions and statements, pattern matching - Loops: for, enhanced for, while, do-while, break, continue, return |
| Topic 8: Using Object-Oriented Concepts | 20% | - Enums, nested classes, local variable type inference - Classes, records, objects, constructors, initializers, methods, fields, encapsulation - Inheritance, abstract classes, sealed classes, interfaces, polymorphism - Overloading, overriding, Object class methods, immutable objects |
| Topic 9: Working with Arrays and Collections | 12% | - Collections Framework: List, Set, Map, Deque, Queue, sorting, searching - Declare, instantiate, initialize, use arrays and multidimensional arrays |
| Topic 10: Concurrency and Multithreading | 10% | - Synchronization, locks, concurrent collections, thread safety - Thread lifecycle, Runnable, Callable, ExecutorService, virtual threads |
1. Given:
java
void verifyNotNull(Object input) {
boolean enabled = false;
assert enabled = true;
assert enabled;
System.out.println(input.toString());
assert input != null;
}
When does the given method throw a NullPointerException?
A) Only if assertions are disabled and the input argument is null
B) A NullPointerException is never thrown
C) Only if assertions are enabled and the input argument isn't null
D) Only if assertions are disabled and the input argument isn't null
E) Only if assertions are enabled and the input argument is null
2. Given:
java
public class BoomBoom implements AutoCloseable {
public static void main(String[] args) {
try (BoomBoom boomBoom = new BoomBoom()) {
System.out.print("bim ");
throw new Exception();
} catch (Exception e) {
System.out.print("boom ");
}
}
@Override
public void close() throws Exception {
System.out.print("bam ");
throw new RuntimeException();
}
}
What is printed?
A) bim boom bam
B) bim boom
C) Compilation fails.
D) bim bam boom
E) bim bam followed by an exception
3. Given a properties file on the classpath named Person.properties with the content:
ini
name=James
And:
java
public class Person extends ListResourceBundle {
protected Object[][] getContents() {
return new Object[][]{
{"name", "Jeanne"}
};
}
}
And:
java
public class Test {
public static void main(String[] args) {
ResourceBundle bundle = ResourceBundle.getBundle("Person");
String name = bundle.getString("name");
System.out.println(name);
}
}
What is the given program's output?
A) JamesJeanne
B) JeanneJames
C) Jeanne
D) James
E) Compilation fails
F) MissingResourceException
4. Given:
java
Object input = 42;
String result = switch (input) {
case String s -> "It's a string with value: " + s;
case Double d -> "It's a double with value: " + d;
case Integer i -> "It's an integer with value: " + i;
};
System.out.println(result);
What is printed?
A) null
B) Compilation fails.
C) It's an integer with value: 42
D) It's a double with value: 42
E) It's a string with value: 42
F) It throws an exception at runtime.
5. Given:
java
var now = LocalDate.now();
var format1 = new DateTimeFormatter(ISO_WEEK_DATE);
var format2 = DateTimeFormatter.ISO_WEEK_DATE;
var format3 = new DateFormat(WEEK_OF_YEAR_FIELD);
var format4 = DateFormat.getDateInstance(WEEK_OF_YEAR_FIELD);
System.out.println(now.format(REPLACE_HERE));
Which variable prints 2025-W01-2 (present-day is 12/31/2024)?
A) format4
B) format1
C) format2
D) format3
Solutions:
| Question # 1 Answer: A | Question # 2 Answer: D | Question # 3 Answer: C | Question # 4 Answer: B | Question # 5 Answer: C |
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