Question 1

Which of the following statements is false?

Accepted Answer

A)  A common way to perform synchronization is to use Java's built-in monitors. 
B)  Every object has a monitor and a monitor lock (or intrinsic lock). 
C)  A monitor ensures that its object's monitor lock is held by a maximum of two threads at a time. 
D)  Monitors and monitor locks can be used to enforce mutual exclusion. 
A)  A common way to perform synchronization is to use Java's built-in monitors. 
B)  Every object has a monitor and a monitor lock (or intrinsic lock). 
C)  A monitor ensures that its object's monitor lock is held by a maximum of two threads at a time. 
D)  Monitors and monitor locks can be used to enforce mutual exclusion.

Question 2

Class Instant's static method ________ gets the current time.

Accepted Answer

A)  currentTime 
B)  immediate 
C)  now 
D)  present 
A)  currentTime 
B)  immediate 
C)  now 
D)  present

Question 3

The main method executes in the ________ thread of execution.

Accepted Answer

A)  starting 
B)  main 
C)  local 
D)  None of the above. 
A)  starting 
B)  main 
C)  local 
D)  None of the above.

Question 4

Which of the following statements is false?

Accepted Answer

A)  Most operating systems support XE "timeslicing" timeslicing, which enables threads of equal priority to share a processor. 
B)  Without timeslicing, each thread in a set of equal-priority threads runs to completion before other threads of equal priority get a chance to execute. 
C)  With timeslicing, even if a thread has not finished executing when its quantum expires, the processor is taken away from the thread and given to the next thread of equal priority, if one is available. 
D)  An operating system's thread scheduler determines which thread runs next. 
A)  Most operating systems support XE "timeslicing" timeslicing, which enables threads of equal priority to share a processor. 
B)  Without timeslicing, each thread in a set of equal-priority threads runs to completion before other threads of equal priority get a chance to execute. 
C)  With timeslicing, even if a thread has not finished executing when its quantum expires, the processor is taken away from the thread and given to the next thread of equal priority, if one is available. 
D)  An operating system's thread scheduler determines which thread runs next.

Question 5

When a thread obtains the monitor lock on an object, then determines that it cannot continue with its task on that object until some condition is satisfied, the thread can call Object method ________; this releases the monitor lock on the object, and transitions the thread waits to the waiting state.

Accepted Answer

A)  waitForOtherThreads 
B)  stop 
C)  waitForCondition 
D)  wait 
A)  waitForOtherThreads 
B)  stop 
C)  waitForCondition 
D)  wait

Question 6

Which of the following statements is false?

Accepted Answer

A)  Thread scheduling is XE "platform dependency" platform independent. 
B)  One simple thread-scheduler implementation keeps the highest-priority thread running at all times and, if there's more than one highest-priority thread, ensures that all such threads execute for a quantum each in round-robin fashion. 
C)  The round-robin process for all highest-priority threads continues until all threads run to completion. 
D)  Most programmers who use Java multithreading will not be concerned with setting and adjusting thread priorities 
A)  Thread scheduling is XE "platform dependency" platform independent. 
B)  One simple thread-scheduler implementation keeps the highest-priority thread running at all times and, if there's more than one highest-priority thread, ensures that all such threads execute for a quantum each in round-robin fashion. 
C)  The round-robin process for all highest-priority threads continues until all threads run to completion. 
D)  Most programmers who use Java multithreading will not be concerned with setting and adjusting thread priorities

Question 7

Streams are easy to parallelize, enabling programs to benefit from enhanced performance on ________ systems.

Accepted Answer

A)  uni-core 
B)  serial 
C)  multi-core 
D)  sequential 
A)  uni-core 
B)  serial 
C)  multi-core 
D)  sequential

Question 8

To obtain a parallel stream, simply invoke method ________ on an existing stream.

Accepted Answer

A)  toParallel 
B)  toStream 
C)  parallel 
D)  toParallelStream 
A)  toParallel 
B)  toStream 
C)  parallel 
D)  toParallelStream

Question 9

Which of the following statements is false?

Accepted Answer

A)  A runnable thread transitions to the blocked state when it attempts to perform a task that cannot be completed immediately and it must temporarily wait until that task completes. 
B)  When a thread issues an input/output request, the operating system blocks the thread from executing until that I/O request completes-at that point, the blocked thread transitions to the runnable state, so it can resume execution. 
C)  A blocked thread cannot use a processor, even if one is available. 
D)  Each of the above statements is true. 
A)  A runnable thread transitions to the blocked state when it attempts to perform a task that cannot be completed immediately and it must temporarily wait until that task completes. 
B)  When a thread issues an input/output request, the operating system blocks the thread from executing until that I/O request completes-at that point, the blocked thread transitions to the runnable state, so it can resume execution. 
C)  A blocked thread cannot use a processor, even if one is available. 
D)  Each of the above statements is true.

Question 10

In a producer/consumer relationship, the ________ portion of an application generates data and stores it in a shared object, and the ________ portion of an application reads data from the shared object.

Accepted Answer

A)  consumer, producer 
B)  producer, consumer 
C)  outputter, inputter 
D)  None of the above. 
A)  consumer, producer 
B)  producer, consumer 
C)  outputter, inputter 
D)  None of the above.

Question 11

NumberFormat static method ________ returns a NumberFormat that's used to format a number as a percentage.

Accepted Answer

A)  percent 
B)  getPercentInstance 
C)  percentage 
D)  toPercent 
A)  percent 
B)  getPercentInstance 
C)  percentage 
D)  toPercent

Question 12

A new thread begins its life cycle by transitioning to the __________ state.

Accepted Answer

A)  runnable. 
B)  waiting. 
C)  terminated. 
D)  new. 
A)  runnable. 
B)  waiting. 
C)  terminated. 
D)  new.

Question 13

Which of the following statements is false?

Accepted Answer

A)  If several synchronized statements in different threads are trying to execute on an object at the same time, only one of them may be active on the object-all the other threads attempting to enter a synchronized statement on the same object are placed in the XE "blocked state" b XE "thread states:blocked" locked state. 
B)  When a synchronized statement finishes executing, the object's monitor lock is released and one of the blocked threads attempting to enter a synchronized statement can be allowed to acquire the lock to proceed. 
C)  Java also allows synchronized methods. Before executing, a synchronized instance method must acquire the lock on the object that's used to call the method. 
D)  Using a synchronized block to enforce mutual exclusion is an example of the design pattern known as the Java Exclusion Pattern. 
A)  If several synchronized statements in different threads are trying to execute on an object at the same time, only one of them may be active on the object-all the other threads attempting to enter a synchronized statement on the same object are placed in the XE "blocked state" b XE "thread states:blocked" locked state. 
B)  When a synchronized statement finishes executing, the object's monitor lock is released and one of the blocked threads attempting to enter a synchronized statement can be allowed to acquire the lock to proceed. 
C)  Java also allows synchronized methods. Before executing, a synchronized instance method must acquire the lock on the object that's used to call the method. 
D)  Using a synchronized block to enforce mutual exclusion is an example of the design pattern known as the Java Exclusion Pattern.

Question 14

Which of the following statements is false?

Accepted Answer

A)  Every Java thread has a thread priority that helps determine the order in which threads are scheduled. 
B)  Each new thread inherits the priority of the thread that created it. 
C)  Informally, higher-priority threads are more important to a program and should be allocated processor time before lower-priority threads. 
D)  Thread priorities guarantee the order in which threads execute. 
A)  Every Java thread has a thread priority that helps determine the order in which threads are scheduled. 
B)  Each new thread inherits the priority of the thread that created it. 
C)  Informally, higher-priority threads are more important to a program and should be allocated processor time before lower-priority threads. 
D)  Thread priorities guarantee the order in which threads execute.

Question 15

Interface ExecutorService provides the ________ method, which returns control to its caller either when all tasks executing in the ExecutorService complete or when the specified timeout elapses.

Accepted Answer

A)  waitForTermination 
B)  wait 
C)  awaitTermination 
D)  None of the above. 
A)  waitForTermination 
B)  wait 
C)  awaitTermination 
D)  None of the above.

Question 16

The ArrayBlockingQueue method ________ returns the number of elements currently in the ArrayBlockingQueue?

Accepted Answer

A)  size. 
B)  length. 
C)  getSize. 
D)  getLength. 
A)  size. 
B)  length. 
C)  getSize. 
D)  getLength.

Question 17

When using Java's built-in monitors, every object has a(n) ________ or a(n) ________ that the monitor ensures is held by a maximum of only one thread at any time.

Accepted Answer

A)  monitor lock, intrinsic lock 
B)  built-in lock, free lock 
C)  mutual exlcusion lock, synchronization lock 
D)  None of the above. 
A)  monitor lock, intrinsic lock 
B)  built-in lock, free lock 
C)  mutual exlcusion lock, synchronization lock 
D)  None of the above.

Question 18

When a thread executing a synchronized statement (or method) completes or satisfies the condition on which another thread may be waiting, it can call Object method ________ or ________ to allow a waiting thread or all waiting threads to transition to the runnable state again.

Accepted Answer

A)  notifyThread, notifyAllThreads 
B)  wakeUpThread, wakeUpAllThreads 
C)  notify, notifyAll 
D)  None of the above. 
A)  notifyThread, notifyAllThreads 
B)  wakeUpThread, wakeUpAllThreads 
C)  notify, notifyAll 
D)  None of the above.

Question 19

It’s recommended that you do not explicitly create and use Thread objects to implement concurrency, but rather use the ________ interface.

Accepted Answer

A)  ExecutorService 
B)  Runnable 
C)  Concurrent 
D)  Executor 
A)  ExecutorService 
B)  Runnable 
C)  Concurrent 
D)  Executor

Question 20

The preferred means of creating multithreaded Java applications is by implementing the ________ interface. An object of a class that implements this interface represents a task to perform.

Accepted Answer

A)  Thread 
B)  Runner 
C)  Runnable 
D)  None of the above. 
A)  Thread 
B)  Runner 
C)  Runnable 
D)  None of the above.

Exam 22: Concurrency

Which of the following statements is false?

Class Instant's static method ________ gets the current time.

The main method executes in the ________ thread of execution.

Which of the following statements is false?

Which of the following statements is false?

Streams are easy to parallelize, enabling programs to benefit from enhanced performance on ________ systems.

To obtain a parallel stream, simply invoke method ________ on an existing stream.

Which of the following statements is false?

In a producer/consumer relationship, the ________ portion of an application generates data and stores it in a shared object, and the ________ portion of an application reads data from the shared object.

NumberFormat static method ________ returns a NumberFormat that's used to format a number as a percentage.

A new thread begins its life cycle by transitioning to the __________ state.

Which of the following statements is false?

Which of the following statements is false?

Interface ExecutorService provides the ________ method, which returns control to its caller either when all tasks executing in the ExecutorService complete or when the specified timeout elapses.

The ArrayBlockingQueue method ________ returns the number of elements currently in the ArrayBlockingQueue?

When using Java's built-in monitors, every object has a(n) ________ or a(n) ________ that the monitor ensures is held by a maximum of only one thread at any time.

When a thread executing a synchronized statement (or method) completes or satisfies the condition on which another thread may be waiting, it can call Object method ________ or ________ to allow a waiting thread or all waiting threads to transition to the runnable state again.

It’s recommended that you do not explicitly create and use Thread objects to implement concurrency, but rather use the ________ interface.

The preferred means of creating multithreaded Java applications is by implementing the ________ interface. An object of a class that implements this interface represents a task to perform.

Introduction to Computers, the Internet and Java

Introduction to Java Applications; Inputoutput and Operators

Introduction to Classes, Objects, Methods and Strings

Control Statements: Assignment, and Operators

Control Statements: Logical Operators

Methods: a Deeper Look

Arrays and Arraylists

Classes and Objects: a Deeper Look

Object-Oriented Programming: Inheritance

Object-Oriented Programming: Polymorphism and Interfaces

Exception Handling: a Deeper Look

Javafx Graphical User Interfaces

Javafx Gui

Strings, Characters and Regular Expressions

Files, Inputoutput Streams, Nio and Xml Serialization

Generic Collections

Lambdas and Streams

Recursion

Searching, Sorting and Big O

Generic Classes and Methods: a Deeper Look

Custom Generic Data Structures

Accessing Databases With Jdbc

Swing Gui Components

Graphics and Java 2d

Networking

Java Persistence Api Jpa

Javaserver Faces Web Apps

Javaserver Faces Web Apps

Swing Gui Components

Filters

In a producer/consumer relationship, the portion of an application generates data and stores it in a shared object, and the portion of an application reads data from the shared object.

When using Java's built-in monitors, every object has a(n) or a(n) that the monitor ensures is held by a maximum of only one thread at any time.

When a thread executing a synchronized statement (or method) completes or satisfies the condition on which another thread may be waiting, it can call Object method or to allow a waiting thread or all waiting threads to transition to the runnable state again.