Question 1

What is multithreaded programming?
A)It's a process in which two different processes run simultaneously.
B)Its a process in which two or more parts of same process run simultaneously.
C)Its a process in which many different process are able to access same information.
D)Its a process in which a single process can access information from many sources.

Accepted Answer

Multithreaded programming refers to a type of programming where two or more threads (parts of the same process) run concurrently, allowing for parallel execution within a single process. This enables more efficient use of resources and faster execution on multi-core processors.

Question 2

Which of these are types of multitasking?
A)Process based multitasking
B)Thread based multitasking
C)Both a & b
D)None of the mentioned

Accepted Answer

D

Question 3

Which of these packages contain all the Java's built in exceptions?
A)java.io
B)java.util
C)java.lang
D)java.net

Accepted Answer

Java's built-in exceptions, such as ArithmeticException, NullPointerException, and IndexOutOfBoundsException, are part of the java.lang package. This package is automatically imported, hence does not require an explicit import statement for its classes.

Question 4

Thread priority in Java is?
A)Integer
B)Float
C)Double
D)Long

Accepted Answer

Thread priority in Java is represented as an integer value.

Question 5

What will happen if two thread of same priority are called to be processed simultaneously?
A)Any one will be executed first lexographically
B)Both of them will be executed simultaneously
C)None of them will be executed
D)It is dependent on the operating system.

Accepted Answer

The execution order of threads with the same priority is dependent on the scheduling policies of the operating system. The OS scheduler determines how threads are prioritized and when each thread gets CPU time, leading to potential variations in execution order.

Question 6

Which of these statements is incorrect?
A)By multithreading CPU's idle time is minimized, and we can take maximum use of it.
B)By multitasking CPU's idle time is minimized, and we can take maximum use of it.
C)Two thread in Java can have same priority
D)A thread can exist only in two states, running and blocked.

Accepted Answer

A thread in Java (and in most threading models) can exist in several states beyond just running and blocked. These typically include new, runnable, waiting, timed waiting, and terminated, making the statement that a thread can exist only in two states incorrect.

Question 7

Which method executes only once
A)start() method
B)init() method
C)stop() method
D)destroy() method

Accepted Answer

The init() method is called only once by the web browser to initialize the servlet. It is used for initial setup, such as resource allocation, and runs only when the servlet is first loaded into memory.

Question 8

Thread class is available in
A)java.io package
B)java.lang package
C)java.awt package
D)java.util package

Accepted Answer

The Thread class is part of the java.lang package, which is automatically imported into all Java programs, hence there's no need to explicitly import this package to use the Thread class.

Question 9

Minimum threads in a program are
A)1
B)2
C)5
D)Many

Accepted Answer

The minimum number of threads in a program is 1, which is the main thread that every program starts with.

Question 10

Interfaces helps in which type of inheritance
A)Multiple inheritance
B)Multilevel inheritance
C)Hierarchical inheritance
D)None of above

Accepted Answer

Interfaces allow a class to inherit from multiple sources, thus enabling multiple inheritance. This is particularly useful in languages like Java, where a class cannot inherit from more than one class but can implement multiple interfaces.

Question 11

Which of these values is returned by read () method is end of file (EOF) is encountered?
A)0
B)1
C)-1
D)Null

Accepted Answer

The read() method returns -1 when the end of the file (EOF) is encountered. This serves as an indicator that there is no more data to be read from the file.

Question 12

Which of these exception is thrown by close () and read () methods?
A)IOException
B)FileException
C)FileNotFoundException
D)FileInputOutputException

Accepted Answer

The close() and read() methods can throw an IOException, which is a general class of exceptions produced by failed or interrupted I/O operations. The other options are not standard Java exceptions related to I/O operations.

Question 13

Which exception is thrown by the read ( ) method of input stream class?
A)Exception
B)ClassNotFoundException
C)read Exception
D)IOException

Accepted Answer

The read() method of InputStream class throws an IOException if an input or output exception occurred.

Question 14

What garbage collection in the context of java?
A)The operating system periodically deletes all of the java files available on the system.
B)Any package imported in a program and not used in automatically deleted.
C)When all references to an object are gone, the memory used by the object is automatically reclaim

Accepted Answer

Garbage collection in Java refers to the process of automatically freeing memory on the heap by deleting objects that are no longer reachable in the program. This is done to prevent memory leaks and ensure efficient memory usage.

Question 15

In order for a source code file, containing the public class test, to successfully compile, which of the following must be true?
A)It must have a package statement
B)It must be named test.java
C)It must import java.lang
D)It must declare a public class named test.

Accepted Answer

The answer of In order for a source code file,...

Question 16

Which of the following are true about the Error and Exception classes?
A)Both classes extend throwable
B)The error class is final and exception class is not.
C)The Exception class is final and the Error is not.
D)Both classes implement Throwable

Accepted Answer

Both Error and Exception classes are subclasses of Throwable, meaning they extend Throwable, not implement it, as Throwable is a class, not an interface. Error class is not final, allowing for the creation of subclasses of Error, and similarly, the Exception class is not final, allowing it to be subclassed.

Question 17

Which of the following are true?
A)The void class extends the class class
B)The float class extends double class
C)The system class extends the runtime class
D)The integer class extends the number class

Accepted Answer

The Integer class is a subclass of the Number class in Java, which provides methods to convert between numbers and strings, and to perform basic numeric operations.

Question 18

How do you create a Reader object from an InputStream object?
A)Use the static createReader() method of InputStream class
B)Use the static createReader() method of Reader class
C)Create an InputStreamReader object passing the InputStream object and an argument to the InputStreamReader constructor.
D)Create an OutputStreamReader object, passing the InputStream object as an argument to the OutputStreamReader constructor.

Accepted Answer

InputStreamReader is designed to convert bytes from an InputStream into characters, making it the correct choice for creating a Reader object from an InputStream.

Question 19

Which of the following is true?
A)The event inheritance model has replaced the event delegation model
B)The event inheritance model is more efficient than event delegation model
C)The event delegation model uses event listeners to define the methods of event handling classes.
D)The event delegation model uses the handleEvent() method to support event handling.

Accepted Answer

The event delegation model indeed uses event listeners to define the methods of event handling classes, allowing for a more flexible and efficient way to handle events, especially in complex applications with many interactive elements.

Question 20

Which of the following is the highest class in the event delegation model?
A)java.util.EventListner
B)java.util.EventObject
C)java.util.AWTEvent
D)java.util.event.AWTEvent

Accepted Answer

java.util.EventObject is the base class for all event classes in the Java event delegation model, making it the highest class in the hierarchy mentioned in the options.

Quiz 9: Java Multithreading and Exception Handling

What is multithreaded programming?

Which of these are types of multitasking?

Which of these packages contain all the Java's built in exceptions?

Thread priority in Java is?

What will happen if two thread of same priority are called to be processed simultaneously?

Which of these statements is incorrect?

Which method executes only once

Thread class is available in

Minimum threads in a program are

Interfaces helps in which type of inheritance

Which of these values is returned by read () method is end of file (EOF) is encountered?

Which of these exception is thrown by close () and read () methods?

Which exception is thrown by the read ( ) method of input stream class?

What garbage collection in the context of java?

In order for a source code file, containing the public class test, to successfully compile, which of the following must be true?

Which of the following are true about the Error and Exception classes?

Which of the following are true?

How do you create a Reader object from an InputStream object?

Which of the following is true?

Which of the following is the highest class in the event delegation model?