1. What are the two types of Streams offered by java 8?

1. 1. random and synchronized

   
   
   

   2. parallel and random

   
   
   

   3. sequential and parallel

   
   
   

   4. sequential and random

   
   
   

   5. None of these

   
   
   

---

1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   Sequential stream and parallel stream are two types of stream provided by java.

---

2. What is Optional object used for?

1. 1. Optional is used to represent null with absent value

   
   
   

   2. Optional means it’s not mandatory for method to return object

   
   
   

   3. Optional is used for optional spring profile

   
   
   

   4. Optional is used for optional runtime argument

   
   
   

   5. None of these

   
   
   

---

1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   Optional object is used to represent null with absent value. This class has various utility methods to facilitate code to handle values as ‘available’ or ‘not available’ instead of checking null values.

---

---

3. What does Files.lines(Path path) do?

1. 1. It counts the number of lines for files at the path specified

   
   
   

   2. It reads all the files at the path specified as a String

   
   
   

   3. It reads all the lines from a file as a Stream

   
   
   

   4. It reads the filenames at the path specified

   
   
   

   5. None of these

   
   
   

---

1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   Files.lines(Path path) that reads all lines from a file as a Stream.

---

4. Which feature of java 8 enables us to create a work stealing thread pool using all available processors at its target?

1. 1. newWorkStealingPool

   
   
   

   2. workPool

   
   
   

   3. workThreadPool

   
   
   

   4. threadPool

   
   
   

   5. None of these

   
   
   

---

1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   Executors newWorkStealingPool() method to create a work-stealing thread pool using all available processors as its target parallelism level.

---

---

5. What is the substitute of Rhino javascript engine in Java 8?

1. 1. V8

   
   
   

   2. Narcissus

   
   
   

   3. Nashorn

   
   
   

   4. Inscript

   
   
   

   5. None of these

   
   
   

---

1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   Nashorn provides 2 to 10 times faster in terms of performance, as it directly compiles the code in memory and passes the bytecode to JVM. Nashorn uses invoke dynamic feature.

---