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Oracle 1z1-830 Exam Syllabus Topics:
| Section | Weight | Objectives |
|---|---|---|
| Working with Arrays and Collections | 12% | - Collections Framework: List, Set, Map, Deque, Queue, sorting, searching - Declare, instantiate, initialize, use arrays and multidimensional arrays |
| Concurrency and Multithreading | 10% | - Synchronization, locks, concurrent collections, thread safety - Thread lifecycle, Runnable, Callable, ExecutorService, virtual threads |
| Advanced Features and Annotations | 3% | - Generics, type parameters, wildcards, type erasure - Annotations, built-in annotations, custom annotations |
| Handling Exceptions | 8% | - Exception hierarchy, try-catch-finally, multi-catch, try-with-resources - Create and use custom exceptions, throw, throws |
| Modules and Packaging | 5% | - Create and use JAR files, modular and non-modular builds - Module system: module-info.java, exports, requires, provides, uses |
| Controlling Program Flow | 10% | - Decision constructs: if-else, switch expressions and statements, pattern matching - Loops: for, enhanced for, while, do-while, break, continue, return |
| Handling Date, Time, Text, Numeric and Boolean Values | 12% | - Manipulate text, text blocks, String, StringBuilder and StringBuffer - Use primitives and wrapper classes, evaluate expressions and apply type conversions - Use Date-Time API: LocalDate, LocalTime, LocalDateTime, Period, Duration, Instant, ZonedDateTime |
| Java I/O and Localization | 5% | - Resource bundles, locale, formatting messages, numbers, dates - File I/O, NIO.2, streams, readers/writers, serialization |
| 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 |
| Using Object-Oriented Concepts | 20% | - Enums, nested classes, local variable type inference - Inheritance, abstract classes, sealed classes, interfaces, polymorphism - Overloading, overriding, Object class methods, immutable objects - Classes, records, objects, constructors, initializers, methods, fields, encapsulation |
Oracle Java SE 21 Developer Professional Sample Questions:
1. Given:
java
Integer frenchRevolution = 1789;
Object o1 = new String("1789");
Object o2 = frenchRevolution;
frenchRevolution = null;
Object o3 = o2.toString();
System.out.println(o1.equals(o3));
What is printed?
A) A NullPointerException is thrown.
B) false
C) true
D) Compilation fails.
E) A ClassCastException is thrown.
2. Given:
java
Object myVar = 0;
String print = switch (myVar) {
case int i -> "integer";
case long l -> "long";
case String s -> "string";
default -> "";
};
System.out.println(print);
What is printed?
A) integer
B) string
C) long
D) Compilation fails.
E) nothing
F) It throws an exception at runtime.
3. Which of the following statements is correct about a final class?
A) The final keyword in its declaration must go right before the class keyword.
B) It cannot implement any interface.
C) It cannot extend another class.
D) It must contain at least a final method.
E) It cannot be extended by any other class.
4. Given:
java
String s = " ";
System.out.print("[" + s.strip());
s = " hello ";
System.out.print("," + s.strip());
s = "h i ";
System.out.print("," + s.strip() + "]");
What is printed?
A) [,hello,h i]
B) [ ,hello,h i]
C) [ , hello ,hi ]
D) [,hello,hi]
5. Given:
java
var counter = 0;
do {
System.out.print(counter + " ");
} while (++counter < 3);
What is printed?
A) 1 2 3 4
B) 0 1 2
C) 0 1 2 3
D) Compilation fails.
E) An exception is thrown.
F) 1 2 3
Solutions:
| Question # 1 Answer: C | Question # 2 Answer: D | Question # 3 Answer: E | Question # 4 Answer: A | Question # 5 Answer: B |
Norman 
Virginia 
Guy 
Milo 
Isaac 
Alfred 
Isaac 
Clara 
Jeffrey 
Maxwell 
Harley 
Nathan 
Martina 
Wordsworth 
Jack 
Zachary 
Honey 
Hobart 
