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Oracle 1z1-830 Exam Syllabus Topics:
| Section | Objectives |
|---|---|
| Controlling Program Flow | - Apply decision statements and loops - Use switch expressions and pattern matching - Work with records and sealed classes |
| Annotations and JDBC | - Execute SQL operations and process results - Connect to databases using JDBC - Use built-in and custom annotations |
| Modules and Packaging | - Manage dependencies and exports - Package and deploy applications - Create and use Java modules |
| Java Concurrency | - Work with concurrent collections and executors - Use virtual threads - Create and manage threads |
| Object-Oriented Programming | - Apply inheritance and polymorphism - Implement encapsulation and abstraction - Create and use classes, interfaces, enums, and records |
| Handling Date, Time, Text, Numeric and Boolean Values | - Use date, time, duration, period, and localization APIs - Work with primitive wrappers and number formatting - Use String, StringBuilder, and related APIs |
| Collections and Generics | - Use sequenced collections and maps - Use List, Set, Map, Queue, and Deque implementations - Apply generics and bounded types |
| Functional Programming | - Work with functional interfaces - Use lambda expressions and method references - Process data using Stream API |
| Exception Handling | - Use try-with-resources - Create custom exceptions - Handle checked and unchecked exceptions |
| Java I/O and NIO | - Use Path, Files, and related APIs - Process file system resources - Read and write files |
Oracle Java SE 21 Developer Professional Sample Questions:
1. Given:
java
double amount = 42_000.00;
NumberFormat format = NumberFormat.getCompactNumberInstance(Locale.FRANCE, NumberFormat.Style.
SHORT);
System.out.println(format.format(amount));
What is the output?
A) 42000
B) 42 k
C) 42000E
D) 42 000,00 €
2. Which StringBuilder variable fails to compile?
java
public class StringBuilderInstantiations {
public static void main(String[] args) {
var stringBuilder1 = new StringBuilder();
var stringBuilder2 = new StringBuilder(10);
var stringBuilder3 = new StringBuilder("Java");
var stringBuilder4 = new StringBuilder(new char[]{'J', 'a', 'v', 'a'});
}
}
A) stringBuilder3
B) stringBuilder2
C) stringBuilder1
D) stringBuilder4
E) None of them
3. Given:
java
List<String> l1 = new ArrayList<>(List.of("a", "b"));
List<String> l2 = new ArrayList<>(Collections.singletonList("c"));
Collections.copy(l1, l2);
l2.set(0, "d");
System.out.println(l1);
What is the output of the given code fragment?
A) [a, b]
B) An IndexOutOfBoundsException is thrown
C) [d]
D) [c, b]
E) [d, b]
F) An UnsupportedOperationException is thrown
4. Given:
java
public class OuterClass {
String outerField = "Outer field";
class InnerClass {
void accessMembers() {
System.out.println(outerField);
}
}
public static void main(String[] args) {
System.out.println("Inner class:");
System.out.println("------------");
OuterClass outerObject = new OuterClass();
InnerClass innerObject = new InnerClass(); // n1
innerObject.accessMembers(); // n2
}
}
What is printed?
A) markdown
Inner class:
------------
Outer field
B) Compilation fails at line n1.
C) An exception is thrown at runtime.
D) Nothing
E) Compilation fails at line n2.
5. What do the following print?
java
public class Main {
int instanceVar = staticVar;
static int staticVar = 666;
public static void main(String args[]) {
System.out.printf("%d %d", new Main().instanceVar, staticVar);
}
static {
staticVar = 42;
}
}
A) 42 42
B) Compilation fails
C) 666 666
D) 666 42
Solutions:
| Question # 1 Answer: B | Question # 2 Answer: D | Question # 3 Answer: D | Question # 4 Answer: B | Question # 5 Answer: A |




