oDesk Java Test v3 Test Answers 2015
·
1. What is the output of the given
program?
public class Test93 {
private int x = 0;
public static void main(String[] args) {
new Test93().test();
}
private int f(int x) { return ++x; }
private int g(int y) { return x++; }
private void test() {
System.out.print( f(x)==f(x) ? "f" : "#" );
System.out.print( g(x)==g(x) ? "g" : "#" );
}
}
Answers:
• ##
• #g
• f#
• fg
2. There are three classes named A, B, and C.
The class B is derived from class A and class C is derived from B. Which of the
following relations are correct for the given classes?
Answers:
• Any instance of
A is an instance of B.
• Any instance of B is an
instance of A.
• Any instance of
C is an instance of B.
• Any instance of
B is an instance of C.
3. What is the output of the given console
application?
public class Test19 {
public static void main(String[] args) {
final int X = 9;
int[][] a = {{5, 4, 3}, {9, 7, 2}, {1, 6, 8}};
for (int i=0; i<3; i++) {
for (int j=0; j<3; j++) {
if (a[i][j] == X) break;
System.out.print(a[i][j]
+ "" "");
}
}
}
}
Answers:
• '5
• 5 4 3
• 5 4 3 1 6 8
• 5 4 3 7 2 1 6 8
4. Which method is called by the servlet
container just after the servlet is removed from service?
Answers:
• public void
finalize() {// code...}
• public void destroy() {//
code...}
• public void
destroy()throws ServletException {// code...}
• public void
finalize()throws ServletException {// code...}
5. What is the output of the given program?
public class Test106 {
public static void main(String[] args) {
Integer x = 0;
Integer y = 0;
Integer a = 1000;
Integer b = 1000;
System.out.println( (a==b) + "; " + (x==y) );
}
}
Answers:
• The code will
not compile, because Integer is a class, and an object must be created by
calling its constructor: Integer a = new Integer(1); or, alternatively, a
primitive type must be used: int a = 1;
• true; true
• false; false
• false; true
6. What is the output of the given program?
public class Test120 extends _Test120 {
{
System.out.print("_INIT");
}
static {
System.out.print("_STATIC");
}
Test120() {
System.out.print("_CONST");
}
public static void main(String[] args) {
System.out.print("_MAIN");
new Test120();
}
}
class _Test120 {
{
System.out.print("_BIN");
}
static {
System.out.print("_START");
}
_Test120() {
System.out.print("_BASE");
}
}
Answers:
•
_START_STATIC_MAIN_BIN_BASE_INIT_CONST
•
_STATIC_START_MAIN_BIN_BASE_INIT_CONST
•
_STATIC_MAIN_START_BIN_BASE_INIT_CONST
•
_START_MAIN_STATIC_BIN_BASE_INIT_CONST
7. What is the output of the given console application?
public class Test31 {
public static void main(String[] args) {
test();
}
public static void test() {
try {
System.out.print("-try");
return;
} catch (Exception e) {
System.out.print("-catch");
} finally {
System.out.print("-finally");
}
}
}
Answers:
• -try
• -try-catch
• -try-finally
• -try-catch-finally
8. What is the output of the given code?
public class Test15 {
public static void main(String[] args) {
VO a = new VO(2);
VO b = new VO(3);
swapONE(a, b);
print(a, b);
swapTWO(a, b);
print(a, b);
}
private static void print(VO a, VO b) {
System.out.print(a.toString() + b.toString());
}
public static void swapONE(VO a, VO b) {
VO tmp = a;
a = b;
b = tmp;
}
public static void swapTWO(VO a, VO b) {
int tmp = a.x;
a.x = b.x;
b.x = tmp;
}
}
class VO {
public
int x;
public VO(int x) {
this.x = x;
}
public String toString() {
return String.valueOf(x);
}
}
Answers:
• 2332
• 3232
• 3223
• 2323
9. What would happen on trying to compile and
run the following code?
class House {
public final void MaintainMethod() {
System.out.println("MaintainMethod");
}
}
public class Building extends House {
public static void main(String argv[]) {
House h = new House();
h.MaintainMethod();
}
}
Answers:
• A runtime error
will occur because class House is not defined as final.
• Successful compilation and
output of "MaintainMethod" at run time.
• A compilation
error indicating that a class with any final methods must be declared final
itself.
• A compilation
error indicating that you cannot inherit from a class with final methods.
10. What is the output of the given program?
public class Test130 {
public static void main(String[] args) {
A a = new A2();
B b = new B2();
System.out.println(a.a + """" + b.b());
}
}
class A {
public int a = 1;
}
class A2 extends A {
public int a = 2;
}
class B {
public
int b() { return 1; }
}
class B2 extends B {
public int b() { return 2; }
}
Answers:
• 11
• 12
• 21
• 22
11. SQLException has a feature of chaining -
identify the right code to execute the same from the following options:
Answers:
• catch(SQLException e) {
out.println(e.getMessage()); while((e=e.getNextException())!=null) {
out.println(e.getMessage()); } }
•
catch(SQLException e) { out.println(e.getNextException());
while((e=e.getMessage())!=null) { out.println(e.getMessage()); } }
• catch(SQLException
e) { out.println(e.getMessage()); while((e=e.getEncapsulatedException())!=null)
{ out.println(e.getMessage()); } }
•
catch(ClassNotFoundException e) { out.println(e.getMessage());
while((e=e.getNextException())!=null) { out.println(e.getMessage()); } }
•
catch(ClassNotFoundException e){ { out.println(e.getMessage()); } }
12. What is the result of an attempt to
compile and run the given program?
public class Test107 {
public static void main(String[] args) {
System.out.println(test());
}
private static int test() {
return (true ? null : 0);
}
}
Answers:
• It gets a
compiler error, because of an attempt to return null from the method with
return type "int".
• It compiles, but throws
NullPointerException at run-time.
• It compiles,
runs, and prints "null" (without quotes).
• It compiles,
runs, and prints "0" (without quotes).
13. Which statements are true regarding
ServletContext Init Parameters in the deployment descriptor?
Answers:
• They are set at
deployment-time, but accessed at run-time.
• They are
accessible from any session within that context.
• They are not
set at deployment-time, but accessed at run-time.
• They are set at
deployment-time and can be updated at run-time.
14. Which of the following methods are members
of the Vector class and allow you to input a new element?
Answers:
• addItem
• append
• insert
• addElement
15. In which class is the notify method
defined?
Answers:
• Thread
• Applet
• Runnable
• Object
16. Which design pattern reduces network
traffic by acting as a caching proxy of a remote object?
Answers:
• DataAccess
Object
•
Model-View-Controller
• Value Object
• Business
Delegate
17. What is the output of the given program?
public class Test89 {
public static void main(String[] args) {
T x = new T("X", null); x.start();
T y = new T("Y", x);
y.start();
T z = new T("Z", y); z.start();
}
}
class T extends Thread {
private Thread predecessor;
private String name;
public T(String name, Thread predecessor) {
this.predecessor = predecessor;
this.name = name;
}
public void run() {
try {
Thread.sleep((int)(Math.random()*89));
System.out.print(name);
} catch (InterruptedException ie) {
ie.printStackTrace();
}
}
}
Answers:
• always XYZ
• always ZYX
• any of the following: XYZ,
XZY, YXZ, YZX, ZXY, ZYX
• any of the
following: XYZ, ZYX
18. The principal finder method that must be
implemented by every entity bean class is:
Answers:
• findByPrimaryKey()
•
ejbGetByPrimaryKey()
• ejbFindPrimayKey()
• getPrimaryKey()
• getFinder()
19. Which option lists Java access modifiers
in the right order from the most permissive to the most restrictive?
Answers:
• public, protected,
<i>no modifier/default/package</i>, private
• public,
<i>no modifier/default/package</i>, protected, private
• <i>no
modifier/default/package</i>, public, protected, private
• public,
protected, private, <i>no modifier/default/package</i>
20. What should be the replacement of
"//ABC" in the following code?
class Krit
{
String str= new
String("OOPS !!! JAVA");
public void
KritMethod(final int iArgs)
{
int iOne;
class Bicycle
{
public void sayHello()
{
//ABC
}
}
}
public void Method2()
{
int iTwo;
}
}
Answers:
• System.out.print(str);
•
System.out.print(iOne);
•
System.out.print(iTwo);
•
System.out.print(iArgs);
21. Assuming that val has been defined as an
int for the code below, which values of val will result in "Test C"
being printed?
if( val > 4 ) {
System.out.println("Test A");
} else if( val > 9 ) {
System.out.println("Test B");
} else
System.out.println("Test C");
Answers:
• val < 0
• val between 0 and 4
• val between 4
and 9
• val > 9
• val = 0
• No values for
val will result in "Test C" being printed.
22. What is the output of the given program?
public class Test118 extends _Test118 {
{
System.out.print("_INIT");
}
static {
System.out.print("_STATIC");
}
Test118() {
System.out.print("_CONST");
}
public static void main(String[] args) {
System.out.print("_MAIN");
new Test118();
}
}
class _Test118 {
_Test118() {
System.out.print("_BASE");
}
}
Answers:
•
_STATIC_MAIN_BASE_INIT_CONST
•
_STATIC_MAIN_INIT_BASE_CONST
•
_INIT_STATIC_MAIN_BASE_CONST
•
_INIT_STATIC_MAIN_BASE_CONST
23. What will be the output, if the following
program is run?
public class Test8 {
public static void
main(String[] args) {
System.out.println(Math.sqrt(-4));
}
}
Answers:
• null
• 2
• NaN
• -2.0
24. What will be the output of this program?
public class Test {
public static void main(String args[]) {
int a, b;
a = 2;
b = 0;
System.out.println(g(a, new int[] { b
}));
}
public static int g(int a, int b[]) {
b[0] = 2 * a;
return b[0];
}
}
Answers:
• 0
• 1
• An exception
will occur
• 4
25. Which of the following statements is true?
Answers:
• public interface
RemoteTrain extends java.rmi.Remote
• public class
RemoteTrain extends java.rmi.Remote
• public
interface RemoteTrain extends java.net.Remote
• public class
RemoteTrain extends java.net.Remote
• private class
RemoteTrain extends java.net.Remote
26. The JDK comes with a special program that
generates skeleton and stub objects that is known as:
Answers:
• java.rmi.Remote
• rmi
• rmic
• rmijava
• javac
27. How many objects are created by the
following code?
Object a, b, c, d, e;
e = new Object ();
b = a = e;
e = new Object ();
Answers:
• 2
• 5
• 4
• That code is
invalid.
28. Which of these interfaces is the most
applicable when creating a class that associates a set of keys with a set of
values?
Answers:
• Collection
• Set
• Map
• SortedSet
29. Which of the following is the correct
syntax for creating a Session object?
Answers:
• HttpSession ses=request.getSession(true);
• HttpSession
ses=getSession(true);
• HttpSession
ses=request.getSession();
• HttpSession
ses=request.getSessionObject(true);
• HttpSession
ses=response.getSession(true);
30. Which statement is true about the given
code?
public class Test78 {
public static void main(String[] args) throws Exception {
new JBean().setHeight(1).setWidth(2).setDepth(3).setDensity(9);
}
}
class JBean {
private int height, width, depth, density;
public
JBean setHeight (int h) { this.height = h; return this; }
public JBean setWidth (int w) { this.width = w; return
this; }
public JBean setDepth (int d) { this.depth = d; return
this; }
public JBean setDensity (int d) { this.density = d; return this; }
}
Answers:
• The code does
not compile, because two setters have a formal parameter with the same name.
• The setters of
the JBean class are JavaBean-compliant.
• The code
compiles, but throws a NullPointerException at run-time.
• The code compiles and
runs.
31. Choose all valid forms of the argument
list for the FileOutputStream constructor shown below:
Answers:
•
FileOutputStream( FileDescriptor fd )
•
FileOutputStream( String n, boolean a )
•
FileOutputStream( boolean a )
•
FileOutputStream()
• FileOutputStream( File f )
32. Which of the following methods should be
invoked by the container to get a bean back to its working state?
Answers:
• EJBPassivate()
• EJBActivate()
• EJBRemove()
• EJBOpen()
33. Select all true statements:
Answers:
• An abstract class can have
non-abstract methods.
• A non-abstract
class can have abstract methods.
• If a
non-abstract class implements interface, it must implement all the methods of
the interface.
• If a
non-abstract class inherits abstract methods from its abstract superclass, it
must implement the inherited abstract methods.
34. Which option could be used to see
additional warnings about code that mixes legacy code with code that uses
generics?
Answers:
• -Xlint:unchecked
•
-Xlint:-unchecked
• -Xswitchcheck
or -Xlint:fallthrough depending on the version of Java
• -classpath or
-cp
35. Assuming the servlet method for handling HTTPGET
requests is doGet(HttpServletRequest req, HTTPServletResponse res), how can the
request parameter in that servlet be retrieved?
Answers:
• String
value=req.getInitParameter(10);
• String
value=req.getInitParameter("product");
• String
value=res.getParameter("product");
• String
value=req.getParameter("product");
36. Which of these is not an event listener
adapter defined in the java.awt.event package?
Answers:
• ActionAdapter
• MouseListener
• WindowAdapter
• FocusListener
37. What would be the result of compiling and
running the following code class?
public class Test {
public static void main(String args[]) {
Test t = new Test();
t.start();
}
public void start() {
int i = 2;
int j = 3;
int x = i & j;
System.out.println(x);
}
}
Answers:
• The code will
not compile.
• The code will
compile but will give a runtime error.
• The code will compile and
print 2.
• The code will
compile and print 1.
38. Which of the following are the methods of
the Thread class?
Answers:
• stay()
• go()
• yield()
• sleep(long
millis)
39. What protocol is used by the
DatagramSocket class?
Answers:
• STCP
• UDP
• TCP
• FTP
• None of the
above
40. Which statements are true? Select all true
statements.
Answers:
• A member
variable can be declared synchronized.
• A class can be
declared transient.
• A class be
declared synchronized.
• A method can be declared
synchronized.
41. Which exception must a setter of a
constrained JavaBean property throw to prevent the property value from changing?
Answers:
• PropertyVetoException
•
IllegalArgumentException
•
IllegalComponentStateException
•
InvalidAttributeValueException
42. X.509 version 3 specifies which of the
following?
Answers:
• A format and content for
digital certificates.
• The IPSec
standard.
• The Secure
Socket Layer.
• The Data
Encryption Standard.
• A file for
digital certificates.
43. What will be the output when this code is
compiled and run?
public class Test {
public Test() {
Bar
b = new Bar();
Bar
b1 = new Bar();
update(b);
update(b1);
b1
= b;
update(b);
update(b1);
}
private void update(Bar
bar) {
bar.x = 20;
System.out.println(bar.x);
}
public static void
main(String args[]) {
new
Test();
}
private class Bar {
int
x = 10;
}
}
Answers:
• The code will
fail to compile.
• 10 10 10 10
• 20 20 20 20
• 10 20 10 20
44. Which of the following methods can be used
for reporting a warning on a Connection object, Statement object &
ResultSet object?
Answers:
• getWarnings()
• getWarned()
• getWarning()
• getError()
• getErrors()
45. Which of the following are valid ways to
define a thread in Java?
Answers:
• Create a subclass of
java.lang.Thread class
• Create a class
that implements java.lang.Runnable
• Define method
run() in a class
• Define method
call() in a class
46. JDBC is based on:
Answers:
• X/Open CLI (Call Level
Interface)
• JDBC/Open CLI
• Java/Open CLI
• V/OPEN CLI
• V/CLOSE CLI
47. Which of the following statements
regarding abstract classes are true?
Answers:
• All methods
declared in an abstract class must be abstract.
• Any subclass
(abstract or concrete class) of an abstract class must implement all the
methods declared in the parent abstract class.
• Any concrete
class must implement all the methods of the parent abstract class which are not
implemented in the super hierarchy tree.
• The abstract class may
have method implementation.
48. Which of the following is the name of the
cookie used by Servlet Containers to maintain session information?
Answers:
• SESSIONID
• SERVLETID
• JSESSIONID
• CONTAINERID
49. Which method in the HttpServlet class
corresponds to the HTTPPUT method?
Answers:
• put
• doPut
• httpPut
• putHttp
50. Which of the following illustrates correct
synchronization syntax?
Answers:
• public
synchronized void Process(void){}
• public void
Process(){ synchronized(this){ } }
• public void
synchronized Process(){}
• public synchronized void
Process(){}
51. The transaction attribute of a bean is set
to 'TX_REQUIRES_NEW.' What can be inferred about its behavior?
Answers:
• It initiates a
new transaction only when the previous one is concluded.
• It initiates a
new transaction without waiting for the previous one to conclude.
• It sends the
request to the EJB container for initiating a new bean.
• The bean manages its own
transaction.
52. How many objects are created in the given
code?
Object x, y, z;
x = new Object();
y = new Object();
Answers:
• 0
• 1
• 2
• 3
53. How does the set collection deal with
duplicate elements?
Answers:
• Duplicate
values will cause an error at compile time.
• A set may
contain elements that return duplicate values from a call to the equals method.
• An exception is
thrown if you attempt to add an element with a duplicate value.
• The add method returns
false if you attempt to add an element with a duplicate value.
54. 1 <libraryPrefix:handlerName
parameterNAme="value">
2 <%=23*counter %>
3 <b>Congratulations!</b>
Which of the following is the correct way to
complete the code snippet above?
Answers:
•
</libraryPrefix:handlerName>
•
</libraryPrefix:handlerName paremeterName="value">
•
</handlerName>
•
<libraryPrefix>
55. Which of the following transaction modes
are supported by Enterprise Java Beans?
Answers:
•
TX_NOT_SUPPORTED
• TX_BEAN_MANAGED
• TX_REQUIRED
• TX_MANDATORY
• All of the above
56. Which distributed object technology is
most appropriate for systems that consist entirely of Java objects?
Answers:
• RMI
• CORBA
• DCOM
• COM
• JDBC
57. The following code was written to save a
handle to an EJBObject named 'bookEJBObject' for an online book shop:
javax.ejb.Handle bookHandle = _____________;
ObjectOutputStream stream = new
ObjectOutputStream(newFileOutputStream(fileName));
stream.writeObject(bookHandle);
stream.close();
Which of the following methods should be
filled in the blank?
Answers:
• (Handle)
bookEJBObject()
• bookEJBObject.getHandle()
• bookEJBObject.getEJBHandle()
•
newHandleInstance()
58. Which sequence will be printed when the
following program is run?
import java.util.*;
public class Test {
public static void main(String str[]) {
List l = new ArrayList();
l.add(''1'');
l.add(''2'');
l.add(1,''3'');
System.out.println(l);
}
}
Answers:
• [1, 3, 2]
• [1, 3, 1]
• [1, 1, 3]
• [1, 1, 2]
• This code will
generate an error.
59. Conventionally, which directory do servlet
class files get placed on?
Answers:
•
WEB-INF\servlets
• webapp\servlets
• WEB-INF\classes
• WEB-INF\
60. Which is a proper way to declare and throw
exception of class XYException?
Answers:
• class XYException extends
Exception {} ... throw new XYException();
• class
XYException implements Exception {} ... throw new XYException();
• class
XYException extends Exception {} ... throw new
Exception(""XYException"");
• class
XYException implements Exception {} ... throw new
Exception(""XYException){};
61. Which of the following JDBC methods is
used to retrieve large binary objects?
Answers:
• getBinaryStream()
• getText()
• getAsciiStream
• getString()
• getUniStream()
62. What is the output of the given program?
public class Test129 {
public static void main(String[] args) {
A a = new A2();
B b = new B2();
System.out.println(a.a + "" + b.b);
}
}
class A { int a = 1; }
class A2 extends A { int a = 2; }
class B { public int b = 1; }
class B2 extends B { public int b = 2; }
Answers:
• 1
• 2
• 11
• 22
63. What exception is thrown by this code, if
arr[j]>arr[j+1]:
public static void main(String[] args) {
int
[]arr={12,23,43,34,3,6,7,1,9,6};
{
int temp;
for (int i=0;i<arr.length;i++)
{
for (int j=0;j<arr.length-i;j++ )
{
if (arr[j]>arr[j+1])
{
temp=arr[j];
arr[j+1]=arr[j];
arr[j+1]=temp;
}
}
}
}
for(int i=0; i<arr.length; i++)
{
System.out.print(arr[i] + " ");
}
}
Answers:
•
NumberFormatException
• ArrayIndexOutOfBoundException
• IOException
64. Which of the following is a well-known
HTTP port?
Answers:
• 21
• 25
• 8080
• 80
• 137
65. Which of these interfaces are used by
implementations of models for JTable?
Answers:
• TableModel
•
TableColumnModel
•
TableSelectionModel
• ListModel
66. Which of the following require explicit
try/catch exception handling by the programmer?
Answers:
• Accessing a
method in another class
• Attempting to open a
network socket
• Attempting to
open a file
• Traversing each
member of an array
67. What is the output of the given program?
public class Test89 {
public static void main(String[] args) {
T x = new T(""X"", null); x.start();
T y = new T(""Y"", x); y.start();
T z = new T(""Z"", y); z.start();
}
}
class T extends Thread {
private Thread predecessor;
private String name;
public T(String name, Thread predecessor) {
this.predecessor = predecessor;
this.name = name;
}
public void run() {
try {
Thread.sleep((int)(Math.random()*89));
System.out.print(name);
} catch (InterruptedException ie) {
ie.printStackTrace();
}
}
}
Answers:
• Always XYZ
• Always ZYX
• Any of the following: XYZ,
XZY, YXZ, YZX, ZXY, ZYX
• Any of the
following: XYZ, ZYX
68. Which of the following code snippets will
take transform input string "2012/06/05" to output string
"05 - 06 - 2012"?
Answers:
• String dateString =
"2012/06/05"; Date date = new
SimpleDateFormat("yyyy/MM/dd").parse(dateString); SimpleDateFormat
sdf = new SimpleDateFormat("dd - MM - yyyy"); System.out.println(sdf.format(date));
• String
dateString = "2012/06/05"; Date date = new
SimpleDateFormat("yyyy/MM/dd").format(dateString); SimpleDateFormat
sdf = new SimpleDateFormat("dd - MM - yyyy");
System.out.println(sdf.parse(date));
• String dateString
= "2012/06/05"; Date date = new SimpleDateFormat("dd - MM -
yyyy").format(dateString); SimpleDateFormat sdf = new
SimpleDateFormat("yyyy/MM/dd"); System.out.println(sdf.parse(date));
• String
dateString = "2012/06/05"; Date date = new SimpleDateFormat("dd
- MM - yyyy").parse(dateString); SimpleDateFormat sdf = new
SimpleDateFormat("yyyy/MM/dd"); System.out.println(sdf.format(date));
69. Which statement is true regarding
ServletContext Initialization Parameters in the deployment descriptor?
Answers:
• They are accessible by all
servlets in a given web application.
• They are
accessible by all servlets in a given session.
• They are
accessible by all servlets in a given HTTP request.
• They are
accessible by all servlets in a given container.
70. Which of the following statements is true
of the HashMap class?
Answers:
• It stores information as
key/value pairs.
• Elements are
returned in the order they were added.
• It does not
permit null keys.
• It does not
permit null values.
71. Which distributed object technology is
most appropriate for systems that consist of objects written in different
languages and that execute on different operating system platforms?
Answers:
• RMI
• CORBA
• COBRA
• DCOM
• COM
72. Which of the following code snippets will
generate five random numbers between 0 and 200?
Answers:
• Random r = new
Random(); for (int i = 0; i < 5; i++) {
System.out.println(r.nextInt(0,200)); }
• Random r = new
Random(200); for (int i = 0; i < 5; i++) { System.out.println(r.nextInt());
}
• Random r = new Random();
for (int i = 0; i < 5; i++) { System.out.println(r.nextInt(200)); }
• Random r = new
Random(200); for (int i = 0; i < 5; i++) { System.out.println(r.nextInt(0));
}
73. What will be the output when this code is
compiled and run?
public class Test {
public Test() {
Bar b = new Bar();
Bar b1 = new Bar();
update(b);
update(b1);
b1 = b;
update(b);
update(b1);
}
private void update(Bar bar) {
bar.x = 20;
System.out.println(bar.x);
}
public static void main(String args[]) {
new Test();
}
private class Bar {
int x = 10;
}
}
Answers:
• The code will
fail to compile.
• 10 10 10 10
• 20 20 20 20
• 10 20 10 20
74. Which class contains a method to create a
directory?
Answers:
• File
• DataOutput
• Directory
• FileDescriptor
•
FileOutputStream
75. Which of the following is the correct
syntax for suggesting that the JVM perform garbage collection?
Answers:
•
System.setGarbageCollection();
•
System.out.gc();
• System.gc();
• System.free();
76. Why can't a Graphics object be created
using the following statement?
Graphics g = new Graphics();
Answers:
• The Graphics
class is a final class.
• The Graphics class is an
abstract class.
• The constructor
of the Graphic class needs a color object to be passed as a parameter, e.g
Graphics g = new Graphics(new Color());.
77. Select all correct statements:
Answers:
• Vector is synchronized,
ArrayList is not synchronized
• Hashtable is
synchronized, HashMap is not synchronized
• Vector is not
synchronized, ArrayList is synchronized
• Hashtable is
not synchronized, HashMap is synchronized
78. What is the output of the given program?
public class Test97 {
public static void main(String[] args) {
int[][] a = new int[2][2];
System.out.println(a.length);
}
}
Answers:
• 0
• 2
• 3
• 4
79. Which of the following is false?
Answers:
• A scrollable
ResultSet can be created in JDBC 2.0 API.
• The cursor is
moved forward using next().
• The cursor is
moved backward using previous().
• A while loop
can be used because next() & previous() methods return false beyond the
resultset.
• A while loop can be used
because next () & previous () methods return -1 beyond the resultset.
80. Consider the following code:
public class Jam {
public void apple(int i,
String s) {
}
//ABC
}
Choose possible valid code replacements of
"//ABC" among the choices:
Answers:
• public void apple(String
s, int i) {}
• public int
apple(int i, String s) {}
• public void
apple(int i, String mystring) {}
• public void
Apple(int i, String s) {}
81. RMI allows remote communication between:
Answers:
• C++ and Java
• C and Java
• Pascal and Java
• Java and Java
• Java and TCP/IP
82. Which of the following interfaces makes it
possible for Java to save an object to a file and turn it into a data stream?
Answers:
•
java.io.Serialization
•
java.net.Serializable
•
java.net.Serialization
• java.io.Serializable
•
java.net.io.Serializable
83. How many objects are created in the given
code?
Object x, y, z;
x = new Object();
y = new Object()
Answers:
• 0
• 1
• 2
• 3
84. As part of the type erasure process, when
compiling a class or interface that extends a parameterized class or implements
a parameterized interface, the compiler may need to create a synthetic method,
called a _________.
Answers:
• bridge method
• helper method
• stub method
• raw method
85. Consider the following code:
public static void main(String bicycle[])
{
System.out.println(bicycle[0]);
}
What would be the result if "java TwoTyre
one two" is entered in the command line?
Answers:
• one
• two
• TwoTyre
• None of the
above
86. With regard to the destroy lifecycle
method, identify the correct statements about its purpose or about how and when
it is invoked.
Answers:
• It gives the servlet an
opportunity to clean up resources.
• Like try-catch,
it is called upon an exception.
• It is rarely
used but can be called to remove a servlet from memory.
• It isn't called
if the server crashes.
87. What is the term to describe a situation
where two or more threads are blocked forever, waiting for each other?
Answers:
• deadlock
• starvation
• livelock
• liveness
88. What will be the output of the following
code?
public class MyTest {
public static void
main(String[] args) {
for
(int i=0; i > 10; i+=2) {
System.out.println(i);
}
}
}
Answers:
• Nothing will be printed.
• It will print
the following output: 0 2 4 6 8
• Compile time
error
• It will print
the following output: 0 1 2 3 4 5 6 7 8 9
89. Which of the following cannot apply to constructors?
Answers:
• Name same as
class name
• Void return
type
• Can have
parameters
• Overloading
90. Which of the following symbols are metacharacters
supported by the java.util.regex API?
Answers:
• .
• \
• @
• #
• EJBActivation()
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