참고: DumpTOP에서 Google Drive로 공유하는 무료 2026 Oracle 1z0-830 시험 문제집이 있습니다: https://drive.google.com/open?id=1AmBBLYlgLRzwVg-ptK6oOZdnX9Y06VCQ
어떻게 하면 가장 편하고 수월하게 Oracle 1z0-830시험을 패스할수 있을가요? 그 답은 바로 DumpTOP에서 찾아볼수 있습니다. Oracle 1z0-830덤프로 시험에 도전해보지 않으실래요? DumpTOP는 당신을 위해Oracle 1z0-830덤프로Oracle 1z0-830인증시험이라는 높은 벽을 순식간에 무너뜨립니다.
| Section | Weight | Objectives |
|---|---|---|
| Functional Programming and Streams | 15% | - Stream API: create, intermediate/terminal operations, parallel streams, grouping, partitioning - Lambda expressions, functional interfaces, method references - Optional class, primitive streams |
| Handling Exceptions | 8% | - Exception hierarchy, try-catch-finally, multi-catch, try-with-resources - Create and use custom exceptions, throw, throws |
| 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 |
| Modules and Packaging | 5% | - Module system: module-info.java, exports, requires, provides, uses - Create and use JAR files, modular and non-modular builds |
| Handling Date, Time, Text, Numeric and Boolean Values | 12% | - Manipulate text, text blocks, String, StringBuilder and StringBuffer - Use Date-Time API: LocalDate, LocalTime, LocalDateTime, Period, Duration, Instant, ZonedDateTime - Use primitives and wrapper classes, evaluate expressions and apply type conversions |
| Using Object-Oriented Concepts | 20% | - Classes, records, objects, constructors, initializers, methods, fields, encapsulation - Enums, nested classes, local variable type inference - Overloading, overriding, Object class methods, immutable objects - Inheritance, abstract classes, sealed classes, interfaces, polymorphism |
| Controlling Program Flow | 10% | - Loops: for, enhanced for, while, do-while, break, continue, return - Decision constructs: if-else, switch expressions and statements, pattern matching |
| Advanced Features and Annotations | 3% | - Annotations, built-in annotations, custom annotations - Generics, type parameters, wildcards, type erasure |
| Java I/O and Localization | 5% | - File I/O, NIO.2, streams, readers/writers, serialization - Resource bundles, locale, formatting messages, numbers, dates |
안심하시고DumpTOP 를 선택하게 하기 위하여, DumpTOP에서는 이미Oracle 1z0-830인증시험의 일부 문제와 답을 사이트에 올려놨으니 체험해보실 수 있습니다. 그러면 저희한테 신뢰가 갈 것이며 또 망설임 없이 선택하게 될 것입니다. 저희 덤프로 여러분은 한번에 시험을 패스할 수 있으며 또 개인시간도 절약하고 무엇보다도 금전상으로 절약이 제일 크다고 봅니다. DumpTOP는 여러분들한테 최고의Oracle 1z0-830문제와 답을 제공함으로 100%로의 보장 도를 자랑합니다, 여러분은Oracle 1z0-830인증시험의 패스로 IT업계여서도 또 직장에서도 한층 업그레이드되실 수 있습니다. 여러분의 미래는 더욱더 아름다울 것입니다.
질문 # 48
Given:
java
var lyrics = """
Quand il me prend dans ses bras
Qu'il me parle tout bas
Je vois la vie en rose
""";
for ( int i = 0, int j = 3; i < j; i++ ) {
System.out.println( lyrics.lines()
.toList()
.get( i ) );
}
What is printed?
정답：B
설명：
* Error in for Loop Initialization
* The initialization part of a for loopcannot declare multiple variables with different types in a single statement.
* Error:
java
for (int i = 0, int j = 3; i < j; i++) {
* Fix:Declare variables separately:
java
for (int i = 0, j = 3; i < j; i++) {
* lyrics.lines() in Java 21
* The lines() method of String returns aStream<String>, splitting the string by line breaks.
* Calling .toList() on a streamconverts it to a list.
* Valid Code After Fixing the Loop:
java
var lyrics = """
Quand il me prend dans ses bras
Qu'il me parle tout bas
Je vois la vie en rose
""";
for (int i = 0, j = 3; i < j; i++) {
System.out.println(lyrics.lines()
toList()
get(i));
}
* Expected Output After Fixing:
vbnet
Quand il me prend dans ses bras
Qu'il me parle tout bas
Je vois la vie en rose
Thus, the correct answer is:Compilation fails.
References:
* Java SE 21 - String.lines()
* Java SE 21 - for Statement Rules
질문 # 49
What does the following code print?
java
import java.util.stream.Stream;
public class StreamReduce {
public static void main(String[] args) {
Stream<String> stream = Stream.of("J", "a", "v", "a");
System.out.print(stream.reduce(String::concat));
}
}
정답：A
설명：
In this code, a Stream of String elements is created containing the characters "J", "a", "v", and "a". The reduce method is then used with String::concat as the accumulator function.
The reduce method with a single BinaryOperator parameter performs a reduction on the elements of the stream, using an associative accumulation function, and returns an Optional describing the reduced value, if any. In this case, it concatenates the strings in the stream.
Since the stream contains elements, the reduction operation concatenates them to form the string "Java". The result is wrapped in an Optional, resulting in Optional[Java]. The print statement outputs this Optional object, displaying Optional[Java].
질문 # 50
Given:
java
public class Test {
class A {
}
static class B {
}
public static void main(String[] args) {
// Insert here
}
}
Which three of the following are valid statements when inserted into the given program?
정답：D,E,F
설명：
In the provided code, we have two inner classes within the Test class:
* Class A:
* An inner (non-static) class.
* Instances of A are associated with an instance of the enclosing Test class.
* Class B:
* A static nested class.
* Instances of B are not associated with any instance of the enclosing Test class and can be instantiated without an instance of Test.
Evaluation of Statements:
A: A a = new A();
* Invalid.Since A is a non-static inner class, it requires an instance of the enclosing class Test to be instantiated. Attempting to instantiate A without an instance of Test will result in a compilation error.
B: B b = new Test.B();
* Valid.B is a static nested class and can be instantiated without an instance of Test. This syntax is correct.
C: A a = new Test.A();
* Invalid.Even though A is referenced through Test, it is a non-static inner class and requires an instance of Test for instantiation. This will result in a compilation error.
D: B b = new Test().new B();
* Invalid.While this syntax is used for instantiating non-static inner classes, B is a static nested class and does not require an instance of Test. This will result in a compilation error.
E: B b = new B();
* Valid.Since B is a static nested class, it can be instantiated directly without referencing the enclosing class.
F: A a = new Test().new A();
* Valid.This is the correct syntax for instantiating a non-static inner class. An instance of Test is created, and then an instance of A is created associated with that Test instance.
Therefore, the valid statements are B, E, and F.
질문 # 51
Given:
java
Map<String, Integer> map = Map.of("b", 1, "a", 3, "c", 2);
TreeMap<String, Integer> treeMap = new TreeMap<>(map);
System.out.println(treeMap);
What is the output of the given code fragment?
정답：G
설명：
In this code, a Map named map is created using Map.of with the following key-value pairs:
* "b": 1
* "a": 3
* "c": 2
The Map.of method returns an immutable map containing these mappings.
Next, a TreeMap named treeMap is instantiated by passing the map to its constructor:
java
TreeMap<String, Integer> treeMap = new TreeMap<>(map);
The TreeMap constructor with a Map parameter creates a new tree map containing the same mappings as the given map, ordered according to the natural ordering of its keys. In Java, the natural ordering for String keys is lexicographical order.
Therefore, the TreeMap will store the entries in the following order:
* "a": 3
* "b": 1
* "c": 2
When System.out.println(treeMap); is executed, it outputs the TreeMap in its natural order, resulting in:
r
{a=3, b=1, c=2}
Thus, the correct answer is option F: {a=3, b=1, c=2}.
질문 # 52
Given:
java
interface A {
default void ma() {
}
}
interface B extends A {
static void mb() {
}
}
interface C extends B {
void ma();
void mc();
}
interface D extends C {
void md();
}
interface E extends D {
default void ma() {
}
default void mb() {
}
default void mc() {
}
}
Which interface can be the target of a lambda expression?
정답：A
설명：
In Java, a lambda expression can be used where a target type is a functional interface. A functional interface is an interface that contains exactly one abstract method. This concept is also known as a Single Abstract Method (SAM) type.
Analyzing each interface:
* Interface A: Contains a single default method ma(). Since default methods are not abstract, A has no abstract methods.
* Interface B: Extends A and adds a static method mb(). Static methods are also not abstract, so B has no abstract methods.
* Interface C: Extends B and declares two abstract methods: ma() (which overrides the default method from A) and mc(). Therefore, C has two abstract methods.
* Interface D: Extends C and adds another abstract method md(). Thus, D has three abstract methods.
* Interface E: Extends D and provides default implementations for ma(), mb(), and mc(). However, it does not provide an implementation for md(), leaving it as the only abstract method in E.
For an interface to be a functional interface, it must have exactly one abstract method. In this case, E has one abstract method (md()), so it qualifies as a functional interface. However, the question asks which interface can be the target of a lambda expression. Since E is a functional interface, it can be the target of a lambda expression.
Therefore, the correct answer is D (E).
질문 # 53
......
우리의 덤프는 기존의 시험문제와 답과 시험문제분석 등입니다. DumpTOP에서 제공하는Oracle 1z0-830시험자료의 문제와 답은 실제시험의 문제와 답과 아주 비슷합니다. DumpTOP는 여러분이 한번에Oracle 1z0-830인증시험을 패스함을 보장 드립니다.
1z0-830인증시험 인기 시험자료: https://www.dumptop.com/Oracle/1z0-830-dump.html
참고: DumpTOP에서 Google Drive로 공유하는 무료 2026 Oracle 1z0-830 시험 문제집이 있습니다: https://drive.google.com/open?id=1AmBBLYlgLRzwVg-ptK6oOZdnX9Y06VCQ