Oracle 1z0-819 Practice Exam Questions

Oracle 1z0-819 Sample Question Answers

Question # 1

Which set of commands is necessary to create and run a custom runtime image from Java source files? 

A. java, jdeps
B. javac, jlink
C. jar, jlink
D. javac, jar

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Question # 2

Which statement about a functional interface is true? 

A. It must be defined with the public access modifier.
B. It must be annotated with @FunctionalInterface.
C. It is declared with a single abstract method.
D. It is declared with a single default method.
E. It cannot have any private methods and static methods.

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Question # 3

Which two statements are true about the modular JDK? (Choose two.) 

A. The foundational APIs of the Java SE Platform are found in the java.base module.
B. An application must be structured as modules in order to run on the modular JDK.
C. It is possible but undesirable to configure modules’ exports from the command line.
D. APIs are deprecated more aggressively because the JDK has been modularized.

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Question # 4

Which two statements are true about Java modules? (Choose two.) 

A. Modular jars loaded from --module-path are automatic modules.
B. Any named module can directly access all classes in an automatic module.
C. Classes found in –classpath are part of an unnamed module.
D. Modular jars loaded from –classpath are automatic modules.
E. If a package is defined in both the named module and the unnamed module, then thepackage in the unnamed module is ignored.

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Question # 5

Which is the correct order of possible statements in the structure of a Java class file? 

A. class, package, import
B. package, import, class
C. import, package, class
D. package, class, import
E. import, class, package

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Question # 6

Which two are successful examples of autoboxing? (Choose two.) 

A. String a = “A”;
B. Integer e = 5;
C. Float g = Float.valueOf(null);
D. Double d = 4;
E. Long c = 23L;
F. Float f = 6.0;

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Question # 7

Which three annotation uses are valid? (Choose three.) 

A. Function func = (@NonNull x) > x.toUpperCase();  
B. var v = “Hello” + (@Interned) “World”
C. Function<String, String> func = (var @NonNull x) > x.toUpperCase();
D. Function<String, String> func = (@NonNull var x) > x.toUpperCase();
E. var myString = (@NonNull String) str;
F. var obj = new @Interned MyObject();

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Question # 8

Which interface in the java.util.function package will return a void return type? 

A. Supplier
B. Predicate
C. Function
D. Consumer

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Question # 9

Given the code fragment:var pool = Executors.newFixedThreadPool(5);Future outcome = pool.submit(() > 1);Which type of lambda expression is passed into submit()?

A. java.lang.Runnable
B. java.util.function.Predicate
C. java.util.function.Function
D. java.util.concurrent.Callable
Answer: D

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Question # 10

Given:var fruits = List.of(“apple”, “orange”, “banana”, “lemon”);You want to examine the first element that contains the character n. Which statement willaccomplish this?

A. String result = fruits.stream().filter(f > f.contains(“n”)).findAny();
B. fruits.stream().filter(f > f.contains(“n”)).forEachOrdered(System.out::print);
C. Optional<String> result = fruits.stream().filter(f > f.contains (“n”)).findFirst ();
D. Optional<String> result = fruits.stream().anyMatch(f > f.contains(“n”));

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