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1. Which of the following is EJB System Exception?

1.javax.ejb.ObjectnotFoundException

2. javax.ejb.EJBException3. javax.ejb.DuplicateKeyException

4. javax.ejb.CreateException

2. Possible to iterate multiple times over an iterator (True or false)

3. class Classname {public static void main(String[] args) {

int[][] a1 = {[1,2,3],[4,5,6],[7,8,9,10]};

System.out.print(a1[0][2]+","+a1[1][0]+","+a1[2][1]);

What is output?

Check.. He declared array elements in []..

Compilation Error -> answer

4. class Classname {

public static void main(String[] args) {

int[][] a1 = {{1,2},{3,4,5},{6,7,8,9},{}};for (int i = 0; i < a1.length; i++) {

System.out.print(a1[i].length+",");}}}

What is the result of attempting to compile and run the program?

a.Prints: 2,3,4,0,

b. Prints: 1,2,5,0,c. Compile-time error

d. Run-time error

e. None of the above

5. Is there any method allows to look next element in an iterator(iterator interface)

without advancing the iterator?ans:da. yes,Iterator.peekb. yes, .nextc. no such methodsd. none of the above

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6. Which of the following are valid types of persistent fields in cmp2.0

a. either collection or setb. classes implement java io serializablec. java primitivesd. entity bean local interface

7.. public Class AQuest{

Public void method (object o){

SOP(Object Version)}

Public void method(String S){

SOP(String Version);PSVM(String arg[]){

AQuest q= new AQuest();

q.method(null);

What will be output?a.Object Version

b.String Version

c.compilation fails

d.runtime error

e. compiles but no output

8. This ques is from SCJP book Collection chapter back Ques:

Given:

public static void main(String[] args) {Queue q = new LinkedList();

q.add("Veronica");

q.add("Wallace");

q.add("Duncan");showAll(q);

}

public static void showAll(Queue q) {q.add(new Integer(42));

while (!q.isEmpty())

System.out.print(q.remove() + " ");}

What is the result?

A) Veronica Wallace Duncan

B) Veronica Wallace Duncan 42

C) Duncan Wallace Veronica

D) 42 Duncan Wallace Veronica

E) Compilation fails.F) An exception occurs at runtime.

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9. which the following methods are used in EJBQL Like that.(choose 2)

a) Select method.

a) finder method.

a) Remove method.

a) Business object method.

10. Which of the following produces a compile time error?

a) int arr[][];//1b) int []arr[];//2c) int []arr[];//3None of the above

11. String str =abc;

Str.concat(def);

Str.concat(gh);

SOP(str);

a)compile time error.

b)abcdefgh;

c)abc;

12. No of finally blocks allowed for a try-catch block..a) always 1b). 0 or 1

13. Given six numbers as a[]=1.6,8.9,-9.6,2.0,0.9,3.5

The output is required as 1.6,-9.6,2.0,8.9,0.9Four options with code in it are given

The codes differs in only one line

A sort function like sort(a,0,4) sort(a,0,3) sort(a,1,3) like that

14. A question on core Java with Options

a). All Objects have a length method.

b). Every object has a equals method. (Every object in java also has a hash

code method)

c) Every object has a sort method

15. class Level1Exception extends Exception {}

class Level2Exception extends Level1Exception {}class Level3Exception extends Level2Exception {}

class Purple {

public static void main(String args[]) {

int a,b,c,d,f,g,x;a = b = c = d = f = g = 0;

x = 3;

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try {

try {switch (x) {

case 1: throw new Level1Exception();

case 2: throw new Level2Exception();

case 3: throw new Level3Exception();} a++; }

catch (Level2Exception e) {b++;}

finally {c++;}}

catch (Level1Exception e) { d++;}

catch (Exception e) {f++;}finally {g++;}

System.out.print(a+","+b+","+c+","+d+","+f+","+g);

}}

011001

16. Find the o/pclass A{

psvm(){

try{badMethod();

s.o.p("A");

}catch(Exception e){ s.o.p("B"); }

finally{ s.o.p("C"); }s.o.p("D");

}

static void badMethod(){}

}

options :

a). Compile time error

b). runtime exception

c). ACD

d). AD

17. Find the o/p

class A{

psvm(){

try{badMethod();

s.o.p("A");

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}

catch(Exception e){ s.o.p("B"); }finally{ s.o.p("C"); }

s.o.p("D");

}

static void badMethod(){throw RuntimeException;

}}

options :

a). Compile time error

b). runtime exception

c). ACD

d). AD

18. which is correct?

a). vectors synchronized. Array lists are not (Array lists are also

heterogenous)

b). vectors are heterogeneous array lists are not

19. Class A, Class B extends A, Class C extends B.A method doIt() is implemented in all

classes. How to call doIt() of A with an instance of C.

a). Super.doIt();b.) this.doIt();

Both the options will cause compilation error

20. In EJB 3.0,all are Plain Old Java Objects(POJO)-T/F -> TRUE

21. class Exception1 extends Exception{}

class Exception2 extends Exception1{}

class Exception3extends Exception2{}class Exception4extends Exception3{}

public class Test{

int a,b,c,d,f;int x=5;

try{

switch(x){case 1: throw new Exception1();

case 2: throw new Exception1();


case 4: throw new Exception1();}

a++;

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}catch(Exception1 e){ b++;}

catch(Exception e){c++}finally{d++}

f++;

}

}System.out.println(a++b+c+d++f);

}

10011

22. package Base;Class Base{

protected void murari();

}

public class Test extends Base.Base{public static void main(String args[]){

Test t= new Test();

t.murari();

}}

What is the output?a) Test class cannot find method in Base classs murari();b) No errors..

Answer: compilation fails

23. class A{

void method() throws ArithmeticException{

}

}

public class C extends A {

void method() throws InterruptedException{

System.out.println("String");}

public static void main(String []args){

}

}

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Which is correct?

a). method() in C class shouldnt throw InterruptedException

b). method() in C class should throw ArithmeticException

24. Which of the following statement is False regarding Tightly Encapsulation?

A). Inner class follows Tightly Encapsulation

b) Anonymous class follows Tightly Encapsulation

Inner classes and anonymous classes in java cannot follow tight

encapsulation. Both of the above options are false.

25. Given a properly prepared String array containing 5 elements which range of results

could a proper invocation of arrays.binarysearch() produce

-6 Through 4

(See the question with option -6 to 4. ( It is is collection question From SCJP 1.5 Book)

26. See the question with options

a). Queuex=new PriorityQueue;

b). LinkedListx=new LinkedList;

. ( It is is collection question From SCJP 1.5 Book)

27. Tasks using a reference to EJBHome

(i) create & remove Session Bean

(ii)get a handle to Session Bean

(iii)create but not remove

28. import java.util.*;class GFC102 {

public static void main (String args[]) {

Object a = new HashSet();System.out.print((a instanceof Set)+",");

System.out.print(a instanceof SortedSet);

}}What is the result of attempting to compile and run the program?

True False

29. import java.util.*;

class GFC102 {

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public static void main (String args[]) {

Object a = new treeSet();System.out.print((a instanceof Set)+",");

System.out.print(a instanceof SortedSet);

}}


True True

30. What do enterprise beans use to communicate with the EJB container to get runtimecontext information?

Thejavax.ejb.EJBContextprovided by the container

A JNDI ENC context

A javax.ejb.EJBHomeobject provided by the containerA javax.ejb.EJBMetaDataobject provided by the container

31. The bean class for an entity that uses the EJB 2.0 model of container-managed

persistence:

Must implement java.io.Serializable

Is only used for better integration with popular IDEs

Must be abstract

Must not be abstract

32. At what point, precisely, in the life-cycle is a container-managed entity beanconsidered created?

Immediately prior to the execution of its ejbCreate() method

Immediately after the execution of its ejbCreate() method

After the CMP bean's data has been committed to the underlying persistent datastore

During the execution of its ejbPostCreate() method

33. What is a deployment descriptor?

An XML file format used by the container to learn about the attributes of a bean,

such as transactional characteristics and access controlA method for transporting enterprise beans back and forth between systems

An XML file used by enterprise bean clients to learn about the attributes of a bean, such

as access control and transactional characteristics.A format for bundling enterprise beans for delivery to customers

34. RuntimeException re=null;

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Throw re;

What will be output?

Exception in thread "main" java.lang.NullPointerException

35. cust1= LocalCustomercust1;Cust2= LocalCustomercust2;

If(cust1.IsIdentical(cust2))

{

If(cust2.IsIdentical(cust1)){

S.O.P(true true);

}Else

S.O.P(false true);If(cust1.IsIdentical(cust1)){

S.O.P(true false);

}

}

What is output?

a). true true

b). false true

c). true false... (The question is not clear. But this is the answer for this question)

Title: SCBCD for the java 2 plat form , Enterprise Edition,

Exam: 310-090,

Version: 12-08-05

From the above PDF document

36 Which two can a Bean Provider do if the OnMessage() of a MDB encounter anapplication problem. (In SCBCD PDF see Question No: 41)

Add the application exception to the methods throw clause

Handle the exception in the method; do not throw the exception

Wrap and rethrow the exception as javax.ejb.EJBException

Wrap and rethrow the exception as javax.ejb.RemoteException

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37 Which two statements about session beans with a remote client view are true? (InSCBCD PDF see Question No: 55)

The Bean Provider must implement the get EJBObject method

The Bean Provider must create a class that implements EJBObject

The Bean Provider is not responsible for implementing the handle classes

The Bean Provider must guarantee that an ejbRemove method is

implemented in the bean class

The bean provider is responsible for ensuring that one thread can be executing an

instance at a time

38 Which statement about the EJB 2.0 container in passivation beans is true? (InSCBCD PDF see Question No: 60)

The container must be able to save and restore a beans reference to a

java:comp/env JNDI context across the beans passivation and activation

39 Which transaction attribute may cause ajavax.transaction.TransactionRequiredException to be thrown? (In SCBCD PDFsee Question No: 69)

Mandatory

40 From which method can a Bean Provider legally invoke create() method on abeans own EJB object reference? (In SCBCD PDF see Question No: 82)

ejbPostCreate

41 Which statement is true about purpose of EJB QL? (In SCBCD PDF seeQuestion No: 126)

EJB QL is used to implement the home methods

42 Which statement describes characteristics method permission defined bydeclarative secure?

-> describes which role may call a method

- > describes a role used in method permissions

( for mapping the roles to respective individuals or for

linking security roles)

43 public class CreditCard {

private String cardID;private Integer limit;

public String ownerName;

public void setCardInformation(String cardID,

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String ownerName,

Integer limit) {this.cardID = cardID;

this.ownerName = ownerName;

this.limit = limit;

}}

Which statement is true?

A. The class is fully encapsulated.B. The code demonstrates polymorphism.

C. The ownerName variable breaks encapsulation.

D. The cardID and limit variables break polymorphism.E. The setCardInformation method breaks encapsulation

44 Through which of the following interface does an application create, find and remove

enterprise beans?

1.javax.ejb.EJBHome2. javax.ejb.EJBObject

3. javax.ejb.EntityBean4. javax.rmi.Remote

45 Which of the following is correct about MDB?1. Can execute in client transactional context

2. All messages from the client services by the same MDB

3. MDBs do not have a client visible identity

4. MDB can hold Client Conversation state

46 Which is not a typical action of a catch block?

1. Partial processing of the exception

2. Complete handling,

3. Throwing exceptions4. Rethrow same exception to the calling environment

47 What is the function of isIdentical() method?

Returns true if two stateless session beans are from the same home

Returns false if two stateful session beans are from the same home

48 Which of the following is the requirement of the message driven bean?

Correct Answers:

1) Must implement MessageDrivenBean and MessageListener interface

2) Class must be public

3) Class cannot be abstract or final

4) Must implement 1 onMessage method

5) Must implement one ejbCreate and one ejbRemove method

6) Must -> public constructor with no args

7) Must not define finalize method

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The correct answer should be any one or more of the above options

49 class Classname {


int[][] a1 = {{1,2,3},{4,5,6},{7,8,9,10}};

System.out.print(a1[0][2]+","+a1[1][0]+","+a1[2][1]);}}


a. Prints: 3,4,8

b.Prints: 7,2,6

c. Compile-time error

d. Run-time errore. None of the above

50 public class Base {}

class Sub extends Base{}class Sub2 extends Base{}

public class CEx{public static void main (String argv[]){

Base b= new base();

Sub s= (sub)b;}

}

Run Time error

Exception in thread "main" java.lang.ClassCastException: cts.dove.com.A

at cts.dove.com.SuperClass.main(SuperClass.java:21)

51 Private class Base{

Base(){

Int i=100;SOP(i);

}

}PSVM(){

Pri p=new pri();

SOP(i);}

}

What is the output?

a. 200b. 100c. 100 followed by 200

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d. Error52 prototype of default constructor

Public class Test{}

a. test(void)b.

test()c. Public Test()

d. Public Test Void()e. Public Test (void)

53 Which of the following are valid types of persistent fields in cmp2.0

a. either collection or setb. classes implement java io serializablec. java primitivesd. entity bean local interface

54 Which valid delivery modes supported in JMS (any 2)a. Durableb. Permanentc. Non-persistenced. Persistence

http://java.sun.com/j2ee/sdk_1.3/techdocs/api/javax/jms/package-summary.html

55 Class Base{PSVM(string arg[]){

SOP (Hello)Public class Test extends Base{}

What is the output?

a) compilation fails

b) Helloc) Runtime

d) No output

(If the class name is Test.java)

If the class name is Base.java -> compilation fails) The public class Test

must be defined in its own file

56 Application Exceptiona. javax.ejb.NoSuchObjectLocalException

b. javax.ejb.duplicatekey

c. javax.ejb.TransactRolledback

d. javax.ejb.TransactRequiredload.

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57 What must be included in the tag

a. b. c. resources -env-ref>d.

58 J2EE support distributed transaction ans:a

a.True

b.False

59 Collection that maintains unique element is called

a. Hashsetb. LinkedListc. ArrayListd. Vector

60 Which statement is correct?a. Exception in case of VM shutdown,if a try block starts to execute acorresponding finally block must always run to completion

b. Exception in case of VM shutdown,if a try block starts to execute a correspondingfinally block will start to execute.

c. An error that might be thrown in a methiod must be declared as thrown by thatmethod or be handled within that method.

d. Multiple catch can catch same class of exception more than once.e. A try statement must have atleat one catch block.

61 Super(),this()

this serves as a reference to the current object whilst super refers to the super class

of the current object.

This keyword can be used inside the methods and constructors

Recall that the this keyword has two meanings: to denote a reference to the implicit

parameter and to call another constructor of the same class. Likewise, the super

keyword has two meanings: to invoke a superclass method and to invoke a

superclass constructor. When used to invoke constructors, the this and super

keywords are closely related. The constructor calls can only occur as the firststatement in another constructor. The construction parameters are either passed to

another constructor of the same class (this) or a constructor of the superclass

(super).

Either super() or this() should be the first call in a constructor but not both.

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Refer to http://www.informit.com/articles/article.aspx?p=1021579

62 . Bean provider takes if the onMessage method of the MDB encounters an application

exception

If the bean method encounters a runtime exception or error, it should simplypropagate the error from the bean method to the container.

If the bean method performs an operation that results in a checked exception

that the bean method cannot recover, the bean method should throw the

javax.ejb.EJBException that wraps the original exception.

Any other unexpected error conditions should be reported using

javax.ejb.EJBException (javax.ejb.EJBException is a subclass of

java.lang.RuntimeException).

Answers:

1) Handle the exception in the method; do not throw the exception

2) Wrap and rethrow the exception as javax.ejb.EJBException

http://docs.sun.com/app/docs/doc/819-4721/6n6rrfqsj?a=view

63 Java.com prefix access

1) Query Iterators

2) Filters3) Pattern Matching Extensions.

It can access preference information by querying. It can edit preferences and

validate preference values.

http://www.ociweb.com/jnb/jnbAug2006.html

64 CMP entity bean retrieves primary key through

a) EntityContext.getIdentity()

b) EntityContext.getPrimaryKey()

c) Bean.getPrimaryKey()d) Bean.getIIdentity()

65 Both session and entity beans can implement local and remote client views, and

generally the same considerations apply. However, an entity bean must implement a local

client view in what situation?a. When the application uses message-driven beans.

b. When the entity bean is a target of a container-managed relationship.

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http://www.informit.com/articles/article.aspx?p=1021579http://docs.sun.com/app/docs/doc/819-4721/6n6rrfqsj?a=viewhttp://www.ociweb.com/jnb/jnbAug2006.htmlhttp://www.ociweb.com/jnb/jnbAug2006.htmlhttp://docs.sun.com/app/docs/doc/819-4721/6n6rrfqsj?a=viewhttp://www.informit.com/articles/article.aspx?p=1021579


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c. When the entity bean is located in a different JVM from the client.

d. When the application uses a session bean as a facade to a set of entity beans.

66 If you use container-managed transaction demarcation, you can set a message-driven

bean to participate in a transaction. To ensure that message delivery from the message

destination to the message-driven bean is part of the subsequent transactional work, setthe message-driven beans transaction attribute (in the deployment descriptor) to ans: C

a. NotSupported

b. Mandatory

c. Required

d. Supports

67 Difference between Iterator and ListIterator?

a) Iterator -> Iterate element in the forward direction, List Iterator ->Iterate element in the bi-directional direction.

b)

Iterator -> Iterate element in the bi-directional direction, List Iterator -> Iterateelement in the forward direction.

c) Iterator -> Iterate element in the bi-directional direction, List Iterator -> Iterateelement in the bi-directional direction.

d) None of the above68 class G03 {private String name;}

class G04 {

private String name;public int a1;

public m1(){ sysout(1); }}

class G05 {

private String name;

private int a1;private m2(){ sysout(2); }

}

Which class is tightly encapsulated?

a) G04b) G05c) G06d) None

69 12. public class AccountManager {

13. private Map accountTotals = new HashMap();

14. private int retirementFund;15.

16. public int getBalance(String accountName) {

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17. Integer total = (Integer) accountTotals.get(accountName);

18. if (total == null)19. total = Integer.valueOf(0);

20. return total.intValue();

21. }

23. public void setBalance(String accountName, int amount) {24. accountTotals.put(accountName, Integer.valueOf(amount));

25. } }

This class is to be updated to make use of appropriate generic types, with no changes in

behavior (for better or worse). Which of these steps could be performed? (Choose three.)

A) Replace line 13 with

private Map accountTotals = new HashMap();

B) Replace line 13 with

private Map accountTotals = new HashMap();

C) Replace line 13 withprivate Map accountTotals = new HashMap();

D) Replace lines 1720 withint total = accountTotals.get(accountName);

if (total == null) total = 0;

return total;

E) Replace lines 1720 with

Integer total = accountTotals.get(accountName);

if (total == null) total = 0;

return total;

F) Replace lines 1720 with

return accountTotals.get(accountName);

G) Replace line 24 with

accountTotals.put(accountName, amount);

H) Replace line 24 with

accountTotals.put(accountName, amount.intValue());

Ans : B , E, and G are correct

70 . Class Alpha(){ }

Class Beta extends Alpha{Beta(){

Sysout(Beta);

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}

Public static void main(String args[]){new Alpha();

new Beta();

}

} What is the output when the program is complies?

a) BetaBetab) Betac) Compilation failsd) Run time error

. 71 Question from EJB-QL : I didnt remember the ques correctly but the options given

below are correct...

Which statement are correct like that (choose 2)

a) select object(A.balance) from account A where ABS(A.balance) GT 1000.0b)

select object(A.balance) from account A where ABS(A.balance) > 1000.0c) select object(A.balance) from account A where ABS(A.balance) > 1000.0

d) select object(A.balance) from account A where SQRT(A.balance) >1000.0

72 void test(){Sysout(test);

Print();

}Public void print(){ }

Public static void print() { }

What is the output of the above program?

a) methods are duplicated.b) Test method will call one or more print() method.c) Compilation fails. -> duplicate methods found

73 Which of the following is correct ?

a)

manager

xyz

b)

manager

c)

xyz

74 which the following are used in EJBQL Like that.(choose 2)

a) Select method.

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a) finder method.

a) Remove method.a) Business object method.

75 Class A{

Public static void main(String args[]){

int a1[][] = { {1,2},{2,3,4},{4,5,6,7} );sysout(Print:+ a1.length);

}

}What is the output?

a) Print:0b) Print:3c) Print:5d) Print:4

76 Which of the following are collection classes?

a) vectorb) Hashset

c) Collectiond) Iterator

77 which methods are in both EJBHome and EJBLocalHome?a) void remove(Handle h)

b) void remove(Object PrimaryKey)

c) get EJBMetaData()d) get HomeHandle

78 Class A11{

Public string tostring() { sysout(A11); }

}Class A12{


All a1[] = new A11[1];All a2[][] = new A11[2][];

All a3[][][] = new A11[][][];

a1[0] = new A11();a2[0] = . = 0;

a3[..] = a3[] = a1;

sysout(a3[4][3][..]); ----> they asked to print the value of some 3d array}

}

Options are like this

a) null

b) All

c) compile time error

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d) runtime error

79 Public static void main(String args[]){

try{

if(args.length==0)

return;sysout(args[0]);

}

finally{sysout(Print);

}

}}

I didnt remember the option.. Options are like

a) arrays out of bound exception

b) If no argument is given it prints the stmt in finally block

c) If one argument is given it prints the argument followed by the finallystmt.

d) If one argument is given it prints the argument alone.

80 Question based on try-catch block.

Class A{


int k=0; int i;try{

int i=1/k;}catch{Arithmetic exception ae){ Sysout(1); }

catch(RuntimeException r){ sysout(2); }

catch(Exception e){ sysout(3); }

finally{ sysout(4); }Sysout(5);

}

}What is the output?

a) prints 1,4,5 in the orderb) prints 2,4 in the orderand some other options.

81 int a1[]={1,2}int a2[]={3,4,5}

int a3[]={6,7,8,9}

sop(a1[0][1]+","+a2[1][2]+","+a3[2][3]);

2, 5, 9

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82 Which of the following produces a compile time error?

a) int arr[2][2];//1b) int [3]arr[3];//2c) int [2]arr[3];//3

83 String str =abc;Str.concat(def);

Str.concat(gh);

SOP(str);

a)compile time error.

b)abcdefgh;

c)abc;

84 JNDI Look Up in

a)EJB Context

b)JNDI Context

85 if( string.toString.equals(string))Sop(true)

else

Sop(false)

Ans : True

86 UDDI is ____________

a)Only Registry

b)only repositoryc)both

87 Java 1.5 written in basic or Java or not?

88 Small amount of data is available,rapid access is needed sort is not required.unique

values are not required. Which will you use?

a)Hash Mapb)Tree Set

c)Linked List

d)Array

89 Passivate in EJB

To send the bean from the ready state to the pooled state. ejbPassivate().

It is a container call back method.


java:comp/env JNDI context across the beans passivation and activation

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90 U need to enter 5 Phone Numbers and only two of them are known.the other threenames would be entered and the numbers would be null..

Four options with a long code are given..

Only thing u need to select is the collection i.e Tree Map Hash Table..Hash Map

91 Fail Fast Iterator In Java or not If yes it is related to Synchronized or

Unsynchronized.

fail-fastterm is about Java collections and theirs iteration and modification, which

are not synchronized.

http://www.javafaq.nu/java-article988.html

92 Question on Container Managed Bean Auto Generated Primary Key..

optional flag to use automatic generation of primary key

automatic-pk

optional flag to specify the name of automatic cmp field generate for pk auto-generated

automatic-pk-field-name

If you specify a java.lang.Object as the primary key class type in ,

but do not specify the primary key name in , then the primary key

is auto-generated by the container

93 A question on core Java with Options

Every Object has a length method.

Every object has an equals() method.

(Every java object has an equals() and a hashCode() method)

http://www.ibm.com/developerworks/java/library/j-jtp05273.html

94 Does List collection provide list iterator?

TRUE

(http://java.sun.com/docs/books/tutorial/collections/interfaces/list.html)

95 Questions on pooled bean like which bean can be considered a part of pooled beans..

Their characteristics..

Stateless session beans -> pooled beans

Entity Beans -> pooled beans, cached beans

Stateful session beans -> only cached beans

Message driven beans -> pooled

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http://docs.sun.com/source/819-0084-10/pt_tuningas.html

96 Message driven bean: what methods will it use for passing messages - >

onMessage(javax.jms.Message msg)

97 class Level1Exception extends Exception {}

class Level2Exception extends Level1Exception {}

class Level3Exception extends Level2Exception {}class Purple {

public static void main(String args[]) {

int a,b,c,d,f,g,x;a = b = c = d = f = g = 0;

x = 3;

try {

try {

switch (x) {case 1: throw new Level1Exception();

case 2: throw new Level2Exception();case 3: throw new Level3Exception();

} a++; }

catch (Level2Exception e) {b++;}finally {c++;}

}

catch (Level1Exception e) { d++;}catch (Exception e) {f++;}

finally {g++;}System.out.print(a+","+b+","+c+","+d+","+f+","+g);

}}


Prints: 0, 1, 1,0,0,1

98 Should finally block always follow the last catch block..(t/f)

False

99 User defined Exceptions -> Custom Exceptions

User Defined Exceptions (Checked Exceptions)

Class Not Found Exception

Clone Not Supported Exception

AWT Exception

IO Exception

File Not Found Exception

EOF Exception

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Interrupted IO Exception

Run Time Exceptions (Unchecked Exceptions)

Arithmetic Exception

Null Pointer ExceptionIndex Out Of Bounds Exception

No Such Element Exception

100 which methods should not be used by container managed beans

Methods used by container managed beans -> ejbcreate, ejbremove, ejbactivate and

ejbpassivate (for stateful session beans) and setsessioncontext,

setmessagedrivencontext and setentitycontext (for respective beans)

101 T/F Does EJB provides support for nested transactions -> False

102 - The EJB QL question (Its there in questions from sun links)

103 which of the following communications are allowed in EJB

options : point to point

send receivebroadcast receive

Answers: 1) Publish and Subscribe

2) point to point

http://www.ibm.com/developerworks/websphere/library/techarticles/0304_yu/yu1.ht

ml

104 If array contains two elements which are equal then after using Arrays.sort methodindex of elements will get changed.

Answer -> False

http://www.leepoint.net/notes-java/data/arrays/70sorting.html

105 Find the o/p

RunTimeException re = null;

throw re;

ans: Option containing NullPointerException

106 Find the o/p

class A{psvm(){

try{

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badMethod();

s.o.p("A");}

catch(Exception e){ s.o.p("B"); }

finally{ s.o.p("C"); }

s.o.p("D");}

static void badMethod(){}

}

options : Compile time error

runtime exception

ACD

AD

107 Find the o/p

class Base{

void abstract method(){};}

class Child extends base

{//some code dont remember

}

Options: Compile time error

Runs and prints o/p

Ans: abstract method declaration contains {}

108 Find the o/p

Class Base{

Base()

{int i = 1;

s.o.p("i : "+i);

}}

class Child extends Base

{public i;

child(int i)

{

super(i);s.o.p(i);

}

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psvm()

{sop(new Child(5));

}

}

The parent class was not having constructor with 1 argument (integer type).

Compilation error

109 class Base

{

static x=1;Base()

{

x+=1;

}

}class Child extends Base

{Child()

}

Compilation Fails

110 Collection Question where queue was created as followingQueue q = new List();

q.add("A");q.add("B");

q.add("c");

then, there was one method

void method(Queue q){

q.add(new Integer("42"));

}psvm()

{

q.reverse();while(q.hasNext)

{

s.o.p(//code for printing element);}

}

Compilation Fails. Interfaces cannot be instantiated (They have instantiated the List

interface in the above code)

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111 class superclass{

private void method(){}

Class subclass extends superclass{

Public void method(){

}Public static void main(String []a){

subclass s=new subclass();

s.method();}

Which method is invoked ie. method present in superclass or subclass

112 class come{

Public static void main(String []a){

Try{

Int i=0;Int y=5/0;

}catch(Exception e){ }catch(ArithmeticException e){ }

}

}

What will be the output? Compilation Error (Unreachable catch block for

Arithmetic Exception)

113 class base{base(int i){

}

}

Class sub extends base{Sub(){ }

Sub(int i){ }

Public void method(){ }

How to invoke the constructor present in base class from subclass

Calling super(i) from either Sub() or Sub(int i)

114 what are the unique features of List.

It can have duplicates

Positional Access

Search

Iteration (Iterator and List Iterator)

Range-view

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http://java.sun.com/docs/books/tutorial/collections/interfaces/list.html

115 Class Exception1 extends Exception{}

Class Exception2 extends Exception{}

Class test{

p.s.v.m (){

try{

}catch(Exception2 2){}

Catch(Exception1 e){}

Catch(Exception e){}}

Public void method() throws Exception1{

Throw new Exception1 ();

}

}Regarding flow

Compilation Error

116 which of the following st are true?

(a)overriding method must have the same signature as overriddenmethod

(b)overriding method can throw exceptions which are not present inoverridden method

three more options are there

The Overriding method must have the same signature, same arguments

(Argument list and Argument order) and same return type as that of the

overridden method

117 multidimensional arrays listing of elementslike a1[]={2,3}

a2[]={2,3,4}

a3[]={3,4,5,6}a[][]={a1,a2,a3}

then the ques will be like

sop(a[0][1]+","+a[1][2]+","+a[2][3])Then they ask you the output

It can be

compilation error

1316

3,4,6

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118 difference between hashtable and hashmap

Hashtable - > Should not contain null values, It is synchronized.

HashMap - > May contain null values, and is not synchronized

119 which is synchronized---vector and hash table are synchronized. Others are notsynchronized.

120 which collection is best for inserting the value in middle Linked list

Linked List -> Slowest Access and Fastest Insertion

121 which collection is worst for inserting value in middle arraylist

http://java.sun.com/developer/JDCTechTips/2002/tt0910.html

122 Arrays.sort one question ---answer is sort 1, 3

123 Inheritance one theoretical ques like inheritance means has a relationship false

Inheritance means IS-A Relationship

124 Message driven bean needs 2 interfaces i.e. messagedrivenbean and

messagelistener

125 Which i/f provides Slowest/Fastest access to middle element?

Slowest - Linked list

Fastest - Array List

http://java.sun.com/developer/JDCTechTips/2002/tt0910.html

126 Class of exceptions tat is unchecked

Arithmetic,

FileNotFound, -> Checked Exception (File Not Found is a sub-type of IO

Exception)

Runtime,

All

127 class B{

psvm(String args[]) {(s.o.p(Hello);

}

}

Public class T extends B{}a) Compilation fails

b) Hello

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c) Runtime

d) No output (If the file name is T.java)

Compilation fails if the class name is B.java, because the public class T must be

defined in its own type

128 Differences bw ArrayList and vector which is synchronized and asynchronized,

which one contains heterogeneous elements

Array list is not synchronized. Vector is synchronized.

Both Array List and Vector can contain heterogeneous elements.

129 Transactions in EJB ->Nested transactions are not allowed, Parallel transactions

are not allowed, EJB supports transactions for all the bean types. EJB also supports

security. EJB supports distributed transactions and security.

130 What all given below are thrown by throw statementError

Object

Exception

Throwable

Runtime Exception

131 Vector can be deleted by which method:

Delete method

Remove method

132 Session Bean can have zero create method-T/F -> False

133 Class A, Class B extends A, Class C extends B.A method doIt() is present. How to

call doIt() of A with an instance of C.Super.doIt();

this.doIt();

Both the options will cause compilation error

134 if((new Object))(.equals((new Object) and some 2 lines code and asked whetherthis will return true or false.

False

135 A superclass A is defined and a subclass B is defined which extends A and one more

class is defines which extends B.

Is it possible to invoke the method of class A using the object of Class C Using superkeyword.

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False

136 public class C {

void method(String s){

System.out.println("String");

}void method(StringBuffer s){

System.out.println("String Buffer");

}public static void main(String []args){

C c = new C();

c.method(null);}

}

Answer: Compilation error (The method (String) is ambiguous) for type C

137. class A{

void method() throws ArithmeticException{ }}


void method()throws InterruptedException{System.out.println("String");

}

public static void main(String []args){ }}

Answer: we should remove interrupted exception

138 class A{

Message msg = new Message();}


void method(){System.out.println(?);

}

public static void main(String []args){C c = new C();

c.method();

}}

class Message{

String text = "hello";

}How do you access text in Message class and print in the method() in Class C

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Options:msg.text,super.msg.text.object.super.msg.text

Answer : msg.text and super.msg.text


public static void main(String []args){String baz = args[3];

System.out.println(baz);

}}

Given the Arguments java test red green blue

Answer:Run time Exception ArrayIndex out of Bounds Exception

140 Differntiate ArrayList and Vector

a) ArrayList is synchronised but vector is not.b) Vector is synchronised but ArrayList is not.

c) Arrays store heterogeneous objects but vector doesnotd) Vector store heterogeneous objects but Arrays doesnot

Answer :B

141 Vector contains Heterogeneous objects. State true or False

Answer:True

142 public class C{public static void main(String []args){

String sad = null;

sad.concat("bha");

sad.concat("rat");System.out.println(sad);

}

}

Answer: RunTime Exception null pointer Exception

143 String sad = "bharat";

sad.concat("bha");sad.concat("rat");

System.out.println(sad);

answer:bharat

144 String sad = "bharat";

String asd = sad.concat("bha");

System.out.println(asd);

Answer:bharatbha

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145 public class C{

public static void main(String []args){if(args.length==0){

sytem.out.println("hi")

return;

System.out.println(args[0]);}

}

Four options are there....CHeck box ...asked to mark two options....

If there is no argument it will print hi

If one argument ...it will print that argument

146 class TestException extends Exception{

}

class FlyingException extends TestException{void method() throws TestException{

}}

public class C{

public static void main(String []args){FlyingException c = new FlyingException();

try {

c.method();} catch (FlyingException e) {

// TODO Auto-generated catch blocke.printStackTrace();

}

}

}

Answer: Compilation Error TestException should present in the Flying

Exception

147 How many Finally blocks can a try-catch block have?

Answer:0 or 1

148 class level1exception extends Exception{ }

class level2exception extends level1exception{ }public class level3exception extends level2exception{

public static void main (String [] args){

int x=2;

int a=b=c=d=f= 0;try{

switch(x) {

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case 1: { throw new level1exception(); }

case 2: { throw new level2exception(); }case 3: { throw new level3exception(); }

}

}catch(level3exception e){ a++; }

catch(level2exception e){ b++; }catch(level1exception e){ c++; }

finally{ d++; }

f++;System.out.println(a+","+b+","+c+","+d+","+f);

}

}

01011

149 public class level3exception{

public static void main (String [] args){Set s = new TreeSet();

s.add("2");s.add("3");

s.add("1");

System.out.println(s);}

}

Answer: [1, 2, 3]

150 Question on Iterator...Check Box which of the following atr true?

1)Iterator is member of Java Collection Framework

2)Iterator is the replacement of Enumeration in Collection Framework.

151 EJB timer objects are like stateless session beans? True or False

152 char c=new char[1],byte b=new byte[1],

float f=new flota[1],object obj=new object[1]sysout(c[1],b[1],f[1],obj[1]);

Array Index Out of Bounds Exception

153 what bean provider should declare in deployment descriptor?

1. Class name -> specifies the fully classified name of the bean class

2. Bean name -> specifies a beans name

3. Transaction type -> Specifies the transaction management type of an EJB

(bean- or container-managed).

http://sarwiki.informatik.hu-berlin.de/Bean_Provider's_Responsibilities

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154 what class should be used for bean to provide programatic security ?

1.EJB metadata context2.client meta data security

An application component provider accesses programmatic security for EJB and

Web components with J2EE platform security APIs.

Javax.ejb.EJBContext -> Answer

http://www.googleperson.wideopen.com/docs/manuals/rhaps/jonas-guide/s1-

security-sec-programmatic.html

155 a collection can refer itself ? true or false

156 methods in EJB home and local home interfaces

EJBHome

getEJBMetaData()

getHomeHandle()

remove(Handle handle)

remove(obj PK)

EJBLocalHome

remove(obj PK)

157 which bean is used to embody business objects

1.enterprise bean

2.entity bean

3.session bean

158 What does the EJB specification architecture define?

A. Transactional componentsB. Distributed object components

C. Server-side components

D. All of the above

159 How can client prepare itself for callbacks from the RMI server?

Extendjava.rmi.server.UnicastRemoteObject

Call UnicastRemoteObject.exportObject()

Either of the above two will work.

160 int []a1={1,2,3}

int[]a2={3,4,5}

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int[]a3={6,7,8,9}

int[][]a={a1,a2,a3}sysout(a[0][1],a[0][2],[0][3])

2, 5, 9

161 class c extends B

B extends A

all implemnts the method doit()then how can we cal the doit() method in A from c

options are like super.doit(),super.this.doit()

Neither of the above options will work.

162. In Test.java

class Base{ public static void main(string args[]){

public void amethod(){System.out.println(Hello);

}

}public class Test extends Base{}

What is the output of the program?The code compiles and runs with out any output

Compilation fails -> (public void amethod())

Runtime error is thrown

The code compiles and prints Hello

163 private class A{//some code here

}

public class B extends A{public static void main(String args[]){

}

}

Compilation Error -> Private Class A

164 valid array declarations

int [] a1[], a2[] ,a3[];

int [][]a1, a2[];

int []a1[];

All the above declarations are valid.

Invalid declaration -> int []a1, []a2; -> some thing like this. The [] in an

array can come either after the identifier or after the type.

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165 class Test{private int cardID;

private int cardNumber;

public String name;

public void setCardID(int cardID){this.cardID=cardID;

}

public int getCardID(){return cardID;

}

public void set cardNumber (int cardNumber){this. cardNumber = cardNumber;

}

public int get cardNumber (){

return cardNumber;

}}

Which of the following statement is true?

The variable name violates the encapsulation

Like that four options are given. I think the above option is correct.

166 four classes are given with some variables and methods. And asked to find which

classes violate the encapsulation.

Class which does not contain private data members (private instance variables) will

violate the Encapsulation -> for example, public String name; This type of

declaration will violate encapsulation.

167 class A{int I=0;

public A(String s){

i=1;}

}

class B extends A{public B(int i){

I=2;

}}

public class C extends B{

public static void main(String args[]){

C c=new C();System.out.println(i);

}

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}

ans: four options are given. But all the options are given. I think it will give

compilation error.

But the options are very close, if it is compilation error also due to which reasonthe error is try to see that also.

Compilation Error

168 class Base{public Integer method(Integer i){

return new Integer(100);

}

public Long method(Long l){

return new Long(200);}

}public class Test{


Base b=new Base();b.method(5);

}

}

For this questions I dont remember the options exactly.

Compilation Fails

169 Difference between Vector and Array list

Vector -> Synchronized

Array List -> Not Synchronized

170 class Exception1 extends Exception{}

class Exception2 extends Exception1{}class Exception3extends Exception2{}

class Exception4extends Exception3{}

public class Test{int a,b,c,d,f;

int x=5;

try{

switch(x){case 1: throw new Exception1();


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case 4: throw new Exception1();}

a++;

}catch(Exception1 e){ b++;}

catch(Exception e){c++}finally{d++}

f++;

}}

System.out.println(a++b+c+d++f);

}in the above question value of x is 5 it is not matching with any of the cases in

switch.

10011

171 Class Base{

//some code here}

public class Test extends Base{

public static void main(String args[]){// some code here

}

}I dont remember the code exactly. But it is like without compiling the base

class test class can get the functionality of the base class.

True

172 package com.base;class Base{

Protected String name;

// some more code}

package com.Test;

class Test extends Base{


// some code here}

}

but in the above code the Base class is not imported in the Test class. The options arevery close. Due to which reason it gives the compilation error.

Remember that compilation error also

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Compilation Error

173 what will happen if catch is not there and only finally is there

Will continue normally or terminate

174 what happens when calling base constructor when u dont have local constructor

The compiler will create a no-argument default constructor only. In order to invoke

a constructor with some arguments inside the base class, a matching constructor

type should be created explicitly in the derived class

175 when a ejb object is in pooled state we need to bring to active state what all methodsneed to call

ejbCreate(), ejbPostCreate() and ejbActivate()

176 equals and hashcodeEquals() returns true -> hashcode() must return true

Equals() returns false-> hashcode() might return false

Hashcode() returns true -> Equals() might return true

Hashcode() returns false -> Equals() must return false

177 bean can use both bmp and cmp at the same time - true or false -> false

CMP and BMP beans can be used in the same application and a bean can be CMP

or BMP, but not both at the same time. They are mutually exclusive.

http://faqs.javabeat.net/ejb/enterprise_java_beans_ejb_interview_questions_4.php

178 message driven bean is stateless or stateful -> stateless

179 how many instances of mdb can run at a time -> many instances can run in parallel

180 vector is heterogenous true or false -> True

181 can tostring used to convert object to string ->True

182 byte[] b=new byte[1];int[] i=new int[1];

long[] l=new long[1];

Object[] o=new Object[1];

System.out.println(b[0]+" "+i[0]+" "+l[0]+" "+o[0]);

Ans: 0 0 0 null

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183 Class which allow bean programmatic security

(i) javax.ejb.EJBContext

(ii) javax.ejb.EJBMetaData

(iii) javax.ejb.Security(iv) javax.ejb.ClientMetaData

Ans: (i)

184 Tasks using a reference to EJBHome

(i) create & remove Session Bean(ii)get a handle to Session Bean


185 FailFastIterator in Java

(i) No failFastIterator concept in Java(ii)FailFastIterator helps in iterating and conditioning.....

2 more options .. don remember




186 Tasks by application assembler

(i)Bind a Resource manage connection factory reference with...(ii) Assign Resource manage connection factory to.....


To link an enterprise bean reference to a target enterprise bean

187 Session bean Passivation

(i)container cannot remove a bean in passivated state(ii)must call stateless session bean ejbPassivate method b4 moving it to bean pool.

(iii) isIdentical () called for passivation

1 more option .. don remember

Passivation and activation are only for stateful session beans. Not for stateless

session beans.

For entity beans, bean cannot be removed after passivation. Results in orphaned

rows in the database table. The method used is ejbPassivate(). It is a container call

back method.


java:comp/env JNDI context across the beans passivation and activation -> Answer

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188 Locating or using a Session bean's Home Interface (correct stmts)

(i)Client can acquire a handle for bean's Local Home Interface(ii) Acquiring Initial Context required for remote clients

(iii)Once acquired by client, can be used multiple times

(iv)Initial Context must be narrowed b4 used.

189 Which java.util.classes & interfaces support event handling?

(i)EventObject

(ii)EventListener

(iii)Both

(iv)None

http://www.geekinterview.com/question_details/25

190 Valid message models in JMS

(i)send/receive

(ii)broadcast/receive

(iii)publish/subscribe(iv)point-to-point

Ans: (iii) and (iv)

191 EJB timer service used with

(i) CMP

(ii)CMP, BMP, MSD

(iii)MSD

(iv)CMP,BMP

192 Iterator is class

true false

Iterator is an interface

193 String str=null;str.append("RAJ");

str.append("kumar");

s.o.p(str);

Compilation Error -> The method append(String) is undefined for the type String.

In the above code, if append is replaced by concat, then a Null Pointer Exception

will be thrown.

194 Collection will extend Cloneable and Serializable Interface? (T/F) false

195 Diff b/n HashTable and HAsh Map---hashtable is ordered version of hashmap..

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ans:HashTable does not allow null values & it is Synchronized. HashMap allows

one null key and multiple null values in a collection. Hash Map is not synchronized.

196 Hash Set s=new Hash Set();--unordered unsorted.

a) s is instanceOf Set-----true

b) s is instanceOf SortedSet----falseOptions:

1) true false 2) false false like this

197 package mypack;

class C {

C() {System.out.println("Default");

}

C(String i) {

System.out.println(i);

}}

class B extends C {B(String s) {

//super(s);

System.out.println(s);}

B() {

this("1", "2");System.out.println("Mytest");

}B(String s1, String s2) {

this(s1 + s2);

}

}public class A extends B {


B b = new B("Test");}

}

Ans: Default Test

In above ques is Super in class B is not commented then o/p is Test Test

198 An Abstract class can extend a non-abstract class (T/F) ans: True

199 Correct about session beansa) Session beans can be private

b) Session beans can be final -> session bean cannot be final

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c) Session beans allow overloading -> method overloading is allowed in EJB

200 valid array declaration of an array choose three

a) int[] a[],b[];

b) int []a,b[];c) int[] a,b[];

d) int[][] a,b[];

I did't remember the exact options

All the above options are correct

Invalid declaration -> int []a1, []a2; -> some thing like this. The [] in an array can

come either after the identifier or after the type.

201 following are valid collection classes

a) List Bag

b) Hash Mapc) Vector

d) Set List

202 True about arrays (increases or decreases) -> decreases

size of array increases performanceinsertion, deletion time

Increasing the size of an array will decrease its performance.

203 Question on when to use throw and throws

Throws is used along with a method signature to specify that a particular method

may throw an exception. A method signature must declare the type of exceptions

that it is expected to throw in throws clause.

A throw statement specifies a particular exception being thrown.

204 Error error=new Error();

error is instanceOf Exception (T/F)

false

205 package mypack;

class Parent {Parent() {

int i=2;

}

}public class Child extends Parent {

Child(){

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int i=1;

}public static void main(String[] args) {

Child b = new Child();

System.out.println(b.i);

}}

ans: compilation error

206 Which i/f provides Slowest/Fastest access to middle element? Linked list/Array List

Slowest access -> Linked List

Fastest access -> Array List

207 class B{

psvm(String args[]) {

(s.o.p(Hello);

}

}

Public class T extends B{}

a) comp fails

b) Hello

c) Runtime

d) No output

208 Class A{

Public static void main(String args[]){int k=0; int i;

try{

int i=1/k;}catch{Arithmetic exception ae){

Sysout(1);

}

catch(RuntimeException r){sysout(2);

}

catch(Exception e){sysout(3);

}

finally{sysout(4);

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}

Sysout(5);}

}

What is the output?a) prints 1,4,5 in the orderb) prints 2,4 in the order

and some other options.

209 A superclass A is defined and a subclass B is defined which extends A and one more

class is defines which extends B.

Is it possible to invoke the method of class A using the object of Class C Using super

keyword. -> False. It is not possible to invoke.



if("String".toString()=="String"){

System.out.println("Equal");

}else{

System.out.println("Not Equal");

}

}

}

Answer: Equal


void method(String s){


}

void method(StringBuffer s){

System.out.println("String Buffer");

}


C c = new C();

c.method(null);

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}

}

Answer: Compilation error

212 class A{

void method() throws ArithmeticException{

}

}

public class C extends A {void method()throws InterruptedException{


}


}

}

Answer: we should remove interrupted exception

213 class A{

Message msg = new Message();

}


void method(){

System.out.println(?);

}

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C c = new C();

c.method();

}

}

class Message{

String text = "hello";

}

How do you access text in Message class and print in the method() in Class C

Options:msg.text, super.msg.text.object, super.msg.text

Answer: msg.text and super.msg.txt

214 In Test.java

class Base{public static void main(string args[]){

public void amethod(){

System.out.println(Hello);}

}

public class Test extends Base{}

What is the output of the program.

a) The code compiles and runs with out any outputb) Compilation failsc) Runtime error is thrownd) The code compiles and prints Hello

215 class Base{

public Integer method(Integer i){

return new Integer(100);}

public Long method(Long l){

return new Long(200);}

}

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public class Test{

public static void main(String args[]){Base b=new Base();

b.method(5);

}

}

For this questions I dont remember the options exactly.

Compilation Fails

216 Given some methods and asked to find vector methods

Remove method is used for deletion

Add method is used for adding the elements

http://java.sun.com/j2se/1.4.2/docs/api/java/util/Vector.html

217 Given some methods and asked to find Object class methods

The following are the methods in Object class:

clone(), equals(Object), finalize(), getClass(), hashCode(), to String(), wait(), notify(),

notifyAll(), wait(long), wait(long,int)

http://bioportal.weizmann.ac.il/course/prog2/java/api/java.lang.Object.html

218 Given one collection object and changed the reference of it in the next line and askedwhether it will through an error or not

219 Class A1{ }

Class A2{A1 [] a1= new A1[2]

A1 [] [] a2 = new A1 [2][2]

A1 [] [] [] a3=new A1 [2][2][2]SOP(a3[2][2][2]);

Array Index Out of Bounds Exception

220 Consider an array List having same objects and it is sent for sorting. After sorting the

arraylist will have the elements in the same order as that of before (True\False) -> False

221 As ArrayList size increases efficiency increases or decreases Increases efficiency

222 Class A{Public static void main(String args[]){

If (args.length


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Sop{True);

} else{Sop(false);

}

What is the output of the above if the program is run with the followingarguments?

A B C d

False

223 Session Bean can be private ( T\F) -> False

224 Given some statements regarding super constructer and asked to pick the correct one.

(Answer: Super will be present implicitly inside a constructer if there is no

argument constructor explicitly defined)

225 Method sort is present in collection class or collection interface ANS.

Collections class

http://java.sun.com/j2se/1.4.2/docs/api/java/util/Collections.html

226 Class A{

Public A(SringBuffer a){SOP{String Buffer);

}Public A(Sring a){

SOP{String );

}

public static void main (String args[]){A a1=new A(null);

}

}

What is the output of the above : . Ans: Compilation error

227 One question on overriding.. Super class method has one return type Sub

class overriding method has one return type.. asked to give the output.

Ans: Compilation Error

228 Differences between vector and ArrayList

Vector -> synchronized

Array List -> not Synchronized

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229 Which is synchronized.. hashmap\ hashtable ->Hash table

230 Which transaction attribute throws TransactionRequired Exception () Ans:

Mandatory

231 Created two objects using EJB create methods. Asked whether two are equal or

not..

232 output of.

String.toString().equals(String) and String.toString() = =String

new Object().equals(new Object()) -> True, True and False

233 How can you remove an element from a Vector?

1) delete method

2) cancel method

3) clear method

4) remove methodAnswer

4) remove method

234 byte[] b=new byte[1];int[] i=new int[1];long[] l=new long[1];

Object[] o=new Object[1];

System.out.println(b[0]+" "+i[0]+" "+l[0]+" "+o[0]);

Ans: 0 0 0 null

235 Tasks using a reference to EJBHome

(i) create & remove Session Bean

(ii)get a handle to Session Bean


236 FailFastIterator in Java

(i) No failFastIterator concept in Java(ii)FailFastIterator helps in iterating and conditioning.....


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237 EJB timer service used with(i) CMP

(ii)CMP, BMP, MSD

(iii)MSD(iv)CMP,BMP

238 Correct about session beans

a)Session beans can be private

b)Session beans can be final

c)Sesson beans allow overloading

etc

239 array list contains values 1.6, 2 ,0.9, 0.2, 3, 1to get the output 1.6, 0.2, 0.9, 2, 3, 1Which of the following statements must be executed.

That means a part of the list must be sorted and should be printed. All the options

contain the same method but the argument values are changing. So see this method whichperforms the above sorting.

Sort(a,1,3)

240 What is the output of the program if the base class is not compiled .

Class Base{

//some code here

}public class Test extends Base{


// some code here

}

}

I dont remember the code exactly. But it is like without compiling the base class test

class can get the functionality of the base class.

241 package com.base;

class Base{

Protected String name;// some more code

}

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package com.Test;

class Test extends Base{


// some code here

}}

but in the above code the Base class is not imported in the Test class. The optionsare very close. Due to which reason it gives the compilation error.

Remember that compilation error also.

Compilation error

242 Requirements of Message Driven Bean

Correct Answers:

1) Must implement MessageDrivenBean and MessageListener interface

2) Class must be public

3) Class cannot be abstract or final

4) Must implement 1 onMessage method

5) Must implement one ejbCreate and one ejbRemove method

6) Must -> public constructor with no args

7) Must not define finalize method

The correct answer should be any of the above options

243 About this() and super()

Either this() or super() should be the first statement inside a constructor

If super() is the first line in a constructor, the second must be this()

The compiler always inserts super() as the first statement in a constructor.

244 Int a[][]={{1,2},{3,4,5},{6,8,9,0});

s.o.p(a[0][0]+ , +a[1][1]+,+a[2][2]);

Ans: 1, 4, 9

245 Class One{

Public One(){this(1)}Public One(String s){this(s+4,base);}

Public One(String a, String b){sop(a+b);}

}Public class Two{

Public Two(){sop(sub);}

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250 Given:Public static void before() {

Set set = new TreeSet ();

set.add("2");

set.add(3);set.add("1");

Iterator it = set.iterator ();

while (it.hasNext())System.out.print (it. next () + " ");

}

Which of the following statements are true?A. The before() method will print 1 2

B. The before() method will print 1 2 3

C. The before() method will print three numbers, but the order cannot be determined.

D. The before() method will not compile.

E. The before() method will throw an exception at runtime.

251 Is the fail fast iterator in java synchronized or unsyncronized?

Ans: Unsynchronized

252 EJB create remove begin methods will be present in

a)EJB Home

b)EJB OBJc)EJB Caller Principal

Ans : a

253 Given a[]=1.6,8.9,-9.6,2.0,0.9,3.5

The output required is 1.6,-9.6,8.9,2.0,0.9,3.5

A sort function like sort(a,0,4) sort(a,0,3) sort(a,1,3) like that Ans: sort(a,1,3)

254 A question on Core Java with options like

a)Every Object has a length method.

b)Every Object has a equals method.

c)Every Object has a sort() method

d)None of these

255 Which of the following is an application Exception

NOsuchObjectException ----system ExceptionEJBException ------------------system Exception

RemoteException------------ system Exception

None of these

APPLICATION EXCEPTIONS include the following

1.createException

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2.DuplicatekeyException

3.FinderException

4.ObjectNotFoundException

5.RemoveException

256 Map m=new TreeMap();

Sop(m instanceof collection)

Ans: False

257 What executes EJB components(EJB container wasnt an option)

1)Application server

2)EJB server

3)Web server

4)Database Server

258 which two elements must be included in the resource ref tag?

Ans: ,

259 When a transaction is rolled back on occurrence of a system exception which of thefollowing occurs?

a) The container removes the bean. -> The bean will be simply discarded.

b) An exception is thrown to the user

c) The exception is rethrown as an remote Exception

260 Correct form of deployment descriptor snippetAns :

. . .

cust

bankCustomer

. . .

261 Valid messaging models Ans: point to point, publish/subscribe

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