Try and practice the latest Oracle : 1z0-830 real questions & answers

Which of the following suggestions compile?(Choose two.)

• A. java
  public sealed class Figure
  permits Circle, Rectangle {}
  final sealed class Circle extends Figure {
  float radius;
  }
  non-sealed class Rectangle extends Figure {
  float length, width;
  }
• B. java
  public sealed class Figure
  permits Circle, Rectangle {}
  final class Circle extends Figure {
  float radius;
  }
  non-sealed class Rectangle extends Figure {
  float length, width;
  }
• C. java
  sealed class Figure permits Rectangle {}
  final class Rectangle extends Figure {
  float length, width;
  }
• D. java
  sealed class Figure permits Rectangle {}
  public class Rectangle extends Figure {
  float length, width;
  }

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A module com.eiffeltower.shop with the related sources in the src directory.
That module requires com.eiffeltower.membership, available in a JAR located in the lib directory.
What is the command to compile the module com.eiffeltower.shop?

• A. css
  CopyEdit
  javac --module-source-path src -p lib/com.eiffel.membership.jar -s out -m com.eiffeltower.shop
• B. css
  CopyEdit
  javac -path src -p lib/com.eiffel.membership.jar -d out -m com.eiffeltower.shop
• C. css
  CopyEdit
  javac --module-source-path src -p lib/com.eiffel.membership.jar -d out -m com.eiffeltower.shop
• D. bash
  CopyEdit
  javac -source src -p lib/com.eiffel.membership.jar -d out -m com.eiffeltower.shop

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Which two of the following aren't the correct ways to create a Stream?

• A. Stream stream = Stream.generate(() -> "a");
• B. Stream<String> stream = Stream.builder().add("a").build();
• C. Stream stream = Stream.empty();
• D. Stream stream = Stream.ofNullable("a");
• E. Stream stream = Stream.of();
• F. Stream stream = new Stream();

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. format2
• B. format3
• C. format1
• D. format4

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Given:
java
Runnable task1 = () -> System.out.println("Executing Task-1");
Callable<String> task2 = () -> {
System.out.println("Executing Task-2");
return "Task-2 Finish.";
};
ExecutorService execService = Executors.newCachedThreadPool();
// INSERT CODE HERE
execService.awaitTermination(3, TimeUnit.SECONDS);
execService.shutdownNow();
Which of the following statements, inserted in the code above, printsboth:
"Executing Task-2" and "Executing Task-1"?

• A. execService.submit(task1);
• B. execService.call(task1);
• C. execService.run(task1);
• D. execService.execute(task2);
• E. execService.call(task2);
• F. execService.submit(task2);
• G. execService.execute(task1);
• H. execService.run(task2);

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