Download Oracle.1z0-813.SelfTestEngine.2020-03-05.33q.tqb
| Vendor: | Oracle |
| Exam Code: | 1z0-813 |
| Exam Name: | Upgrade to Java SE 8 OCP |
| Date: | Mar 05, 2020 |
| File Size: | 2 MB |
Demo Questions
Question 1
Given the code fragment:
Which should be inserted into the line n1 to print Average = 2.5?
- Stream str = Stream.of(1, 2, 3, 4);
- IntStream str = IntStream.of(1, 2, 3, 4);
- DoubleStream str = Stream.of(1.0, 2.0, 3.0, 4.0);
- IntStream str = Stream.of(1, 2, 3, 4)
Correct answer: B
Explanation:
Use IntStream. Reference: https://docs.oracle.com/javase/8/docs/api/java/util/stream/IntStream.html Use IntStream.
Reference: https://docs.oracle.com/javase/8/docs/api/java/util/stream/IntStream.html
Question 2
Given the interface:
Which class implements IdGenerator in a thread-safe manner, so that no threats can get a duplicate id value during concurrent access?
Correct answer: B
Explanation:
An AtomicInteger is used in applications such as atomically incremented counters, and cannot be used as a replacement for an Integer. However, this class does extend Number to allow uniform access by tools and utilities that deal with numerically-based classes. The incrementAndGet() method atomically increments by one the current value. Reference: http://docs.oracle.com/javase/8/docs/api/java/util/concurrent/atomic/AtomicInteger.html#incrementAndGet-- An AtomicInteger is used in applications such as atomically incremented counters, and cannot be used as a replacement for an Integer. However, this class does extend Number to allow uniform access by tools and utilities that deal with numerically-based classes.
The incrementAndGet() method atomically increments by one the current value.
Reference: http://docs.oracle.com/javase/8/docs/api/java/util/concurrent/atomic/AtomicInteger.html#incrementAndGet--
Question 3
Given the code fragment:
Which is the valid definition for the Greeter interface to enable the code fragment to print Kathy Welcome!?
Correct answer: A
Explanation:
Code example works fine: Code example works fine:
