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This class is useful for a Client that wants to connect to a TCP/IP service. Out

ID: 3858021 • Letter: T

Question

This class is useful for a Client that wants to connect to a TCP/IP service.

OutputStream

ObjectOutputStream

Connection

Socket

3 points

You are storing data objects in a HashSet.
Which methods must be properly implemented in your
data objects (Check all that apply)

cloneable

compareTo (implementing the Comparable interface)

clone

equals

sort

hashCode

3 points

Which data structures would be helpful for creating a stack type of data structure

HashMap

TreeSet

HashSet

ArrayList

3 points

The output will be:
MI OH

A compile error occurs on the iterator call
(line number 11)

The output will be:
MI=Lansing OH=Columbus

The output will be:
Lansing Columbus

3 points

You are storing data objects in a TreeSet.
Which methods should be properly implemented in your
data objects (Check all that apply pick 2).

compareTo (implementing the Comparable interface)

equals

sort

cloneable

clone

hashCode

3 points

The System will throw an "Unhandled Mouse Click" exception when it discovers that the MouseListener is never connected.

A compile error will result once Eclipse discovers that it has a class that implements MouseListener, but this class is never passed to the system.

No Compile error or runtime error. However, when our code executes we will not be informed of Mouse clicks.

A runtime exception will occur when we exit the constructor, because the system will detect an unconnected MouseListener

3 points

this method needs to be implemented if your class implements the Runnable interface.

run

start

execute

sleep

3 points

This Java package deals with Graphical user interfaces. The original approach used platform specific code for drawing objects, but this package provided a more consistent Java approach to implementing components like buttons, drop down boxes, etc.

graphics

awt

swing

java_graphics

3 points

This is an interface that is used for classes which are interested in managing the location and sizes of all of the components in a container.

LayoutManager

ComponenentListener

ComponentManager

LayoutListener

3 points

this method is defined in the ActionListener interface.

actionEvent

action

event

actionPerformed

3 points

The following block of code creates a Thread using a Runnable target:

Runnable target = new MyRunnable();
Thread myThread = new Thread (target);

Which of the following classes can be used to create the target, so that the preceding code compiles correctly?

public class MyRunnable implements Runnable{
public void run() {/* Some Code */}
}

public class MyRunnable extends Object {
public void run() {/* Some Code */}
}

public class MyRunnable implements Thread{
public void run(){/* Some Code */}
}

public class MyRunnable extends Runnable{
public void run(){ /* Some Code */}
}

3 points

This class has methods that allow you to create directories, delete files, and rename files.

fileSystem

Directory

File

FileSystem

3 points

3 points

The program aborts with an exception

A compile error at line 11 will occur because doit needs to surround the throw statement with try-catch logic, or change it's declaration to:
void doit throws MyError1

The program will run and generate the output "Exception"

The program will run and generate the output "MyError1"

The program will run and generate the output "RuntimeException"

3 points

This low level abstract class is used for reading a stream of bytes

FileInputStream

Reader

InputStream

ObjectInputStream

3 points

This class provides buffering for OutputStreams. This class has a lot of overloaded methods named either print or println.

PrintStream

FileStream

Writer

WriteStream

OutputStream

ObjectOutputStream

Connection

Socket

Explanation / Answer

Question 30

This class is useful for a Client that wants to connect to a TCP/IP service.

ans: Socket

Socket class is used to connect to network using TCP/IP protocol.

this class is found in java.net packages.

other options OutputStream, ObjectOutputStream, Connection are irellavant to TCP/IP

Question 31

You are storing data objects in a HashSet.

Which methods must be properly implemented in your

data objects (Check all that apply)

ans: equals and hashCode

these methods are useful for comapring the object on basic calculated hashCode.

if u dont implement it java will manupulate default hashCode and equals method.

others are utitlity methods and are already implemented

Question 32

Which data structures would be helpful for creating a stack type of data structure.

ans:ArrayList

another options HashSet and HashMap are not applicaple becuase they do not have gurantied insertion order and

also dont allow to insert duplicate element. And TreeSet have naturally sorting which sorts the data.

ArrayList follows the insertion order which is very required in stack and also allow duplicate objects.

Question 33

image boken, question incomplete

Question 34

You are storing data objects in a TreeSet.

Which methods should be properly implemented in your

data objects (Check all that apply pick 2).

ans: equals and hashCode

these methods are useful for comapring the object on basic calculated hashCode.

if u dont implement it java will manupulate default hashCode and equals method.

Question 35

image boken, question incomplete

Question 36

this method needs to be implemented if your class implements the Runnable interface.

ans : run

Runnable interface have only one abstract method run.

when u implement the Runnable so you have to implement this.

other options are irellavant.

Question 37

This Java package deals with Graphical user interfaces. The original approach used platform specific code for drawing objects,

but this package provided a more consistent Java approach to implementing components like buttons, drop down boxes, etc.

ans: swing

swing are built on top of awt and are platform independent.

other options graphics and java_graphics are not valid packages.

Question 38

This is an interface that is used for classes which are interested in managing the location and sizes of all of the components in a container.

ans : LayoutManager

LayoutManager is responsible for managing the location of components.

and class ComponentListener are used for event of components.

other options ComponentManager and LayoutListener are not valid classes/interface in java.

Question 39

this method is defined in the ActionListener interface.

ans : actionPerformed

this is the only method in ActionListener interface

used to track the actions events.

other options are invalid as they not defined in ActionListener.

Question 40

The following block of code creates a Thread using a Runnable target:

Runnable target = new MyRunnable();

Thread myThread = new Thread (target);

Which of the following classes can be used to create the target, so that the preceding code compiles correctly?

ans :

public class MyRunnable implements Runnable{

public void run() {/* Some Code */}

}

MyRunnable class implementing the Runnable interface and also implemented the run method.

others options are valid because:

public class MyRunnable extends Object {

public void run() {/* Some Code */}

}

run() method is only in Runnable interface and Thread class.

public class MyRunnable implements Thread{

public void run(){/* Some Code */}

}

Thread is class and it cannot be implemented it only can extended.

public class MyRunnable extends Runnable{

public void run(){ /* Some Code */}

}

Runnable is an interface and it can be extende by interface only and other class have to implement interface

Question 41

This class has methods that allow you to create directories, delete files, and rename files.

ans : File

File class have different-different methods for creating directories,and mulitple file operations.

other option fileSystem and Directory are not valid class in java.

and FIleSystem is an abstract class used for getting the fileSystem of OS.

Question 42

This method is in the Graphics class and is useful for displaying text on a screen

ans : drawString

drawString is only method in Graphics that used to draw string.

other options text,displayString,drawListener are not valid methods of Graphics

Question 43

image boken, question incomplete

Question 44

This low level abstract class is used for reading a stream of bytes

ans : InputStream

this is super classes who representds all bytes stream as input.

other option Reader is responsible for reading the character stream.

and FIleInputStream and ObjectInputStream are not an abstract class,

Question 45

This class provides buffering for OutputStreams. This class has a lot of overloaded methods named either print or println.

ans : PrintStream

this class have all the printstream classed.

//please do let me know if u have any doubts...