Q. What will happen if you write System.exit(1) in your code?
July 21st, 2008The JVM will shut down.
Q. How to make sure that I have single instance of class using singleton pattern in cluster environment?
July 21st, 2008In cluster environment the singleton class object should be put in JNDI tree. In this way applications will take the object of the instance from the JNDI tree instead of creating object in every application.
Q. What will happen if two servlets have same url-pattern in web.xml?
July 21st, 2008Suppose you have servlet A and servlet B, and utl pattern for both is /myservlet, then in this case the servlet to be called depends whose url pattern is declares last in web.xml. The concept is simple internally web container would be maintaining map to store the url to servlet mapping, so the servlet mapping declared last would be called.
Q. Does web container and ejb container runs in same JVM in application server?
July 21st, 2008Yes both web container and ejb container of application server runs in same jvm.
Q. In java which one to use Abstract class or Interface?
July 21st, 2008Use abstract class if you are sure that there can be more specialized subclasses of abstract class and there is really a logical is a relationship. Don’t use abstract class just for code reuse. User interface to encapsulate behavior and let concrete subclasses to implement that behavior. An alternate approach could be to use abstract class to have common implementation and for the behavior which is gonna vary use composition for the varying behavior. This is what is strategy pattern.
Q. Explain inheritance in java?
July 21st, 2008In object oriented programming inheritance means inheriting the behavior and state of the parent class. Parent class is called as super class and classes inheriting the behavior and state are called as sub classes. In java there are two notion of inheritance one is implementation inheritance and other is interface inheritance. The purpose of inheritance is not code reuse; code reuse is just the goal of the inheritance.
Implementation inheritance: - Implementation inheritance means inheriting the behavior of the parent class (i.e. methods), this way we achieve code reuse. This is done by extending the class. Even sub classes can override the behavior of the parent class. This is a logical “is a” relationship between the super class and sub class.
Interface inheritance: - Interface inheritance means inheriting the behavior (method) definition and not the behavior itself. The sub classes inherit the behavior definition and implement the behavior by their own. Interface inheritance is also known as sub typing, because interface defines a type and all classes which implements interfaces are subtypes. Here no behavior is implemented in interface, all behaviors is to be implemented by the concrete classes which implements interface. Interface is defining a contract and all classes have to implement the contract. Through interface inheritance we are relating the otherwise unrelated class. The goal of inheritance through interface is not code reuse but to get polymorphic behavior. We can still get code reuse through composition.
Difference between two:-
1. In implementation inheritance the subclasses are bound to the super class. If they are using the super class behaviors then they are bound to those behaviors which are common to all sub classes. Question arises I can override the behavior in a way I want in subclass. That’s ok but as application grows, its not write to change the code in a class. This principle is called as open close principle “class should be open for extension but close for modification”. Also if subclass is depending on the behavior implementation in super class then if in future if I want to change the behavior implementation in super class I have to consider subclasses also as they depend on the implementation of behavior not on behavior itself. Let’s take a simple example: - I have a class called as Bird:-
public class Bird {
public String sing() {
return “chi chi”;
}
}
I can have subclasses of bird as Bird1, Bird2, Bird3, and Bird4
All classes uses the behavior of sing() of class Bird except Bird1 which sings in a different way:-
Public class Bird1 {
public String sing() {
return sing() + “koo koo”;
}
}
Here Bird1 is depends on sing() behavior implementation. If in future I want to change the behavior of sing() (instead of chi chi I want to change it to ki ki), all subclasses will remain intact except Bird1 as its relying on the implementation of behavior of Bird. I have to do changes in Bird1 sing also. This is why we say in implementation inheritance subclasses gets locked to the super class behavior. In implementation inheritance all subclasses are related to each other through a common behavior of super class.
In interface inheritance subclasses are not bound to the behavioral implementation of the interface as there is no implementation. They have to implement the behavior defined interface. Now why we say through interface inheritance we are relate the otherwise unrelated class. Let’s take an example: - suppose I have a Person class and its subclasses as Employee, Student, Teacher etc. Now you see relationship between Person and subclasses is pure is a relationship. Now what if I want to give Student as a behavior of singer. One way is to have sing method in Person with default implementation and lets subclasses override and implement that. But in this way I am making Employee and Teacher a singer which they are not. Second way is to have a Singer interface have sing() method in that and let Student implement that method. This is looking good as only student will behave as a singer. Also in the Bird example I can modify the Bird class and instead of the sing() method Bird class now implement Singer reference and provide the default implementation of sing() method. So in this way Student and Bird class are related to each other they are both Singer. That’s why we say interface implementation relates otherwise unrelated class.
Multiple java/j2ee openings
July 9th, 2008Opening in i-flex mumbai
The skills requirements are:
Good technical understanding of J2EE (EJB), web services, XML/XSL, Oracle/DB2, PL/SQL, database design using UML or ERWin etc
Good communication and presentation skills
Exp between 3-6 years
Willing to undertake short term travel – few days to few weeks on a regular basis
Job content will be writing proposals, solution architecting, making presentations etc
Job location : Mumbai
PLEASE APPLY ONLY IF YOU ARE READY TO RELOCATE YOURSELF TO MUMBAI
Pls apply immediately if you are interested for the above with the following details:
Name of the Candidate
Company
Yrs of Experience
Skill Set
Current CTC
Expected CTC
Notice Period
Education Period / Year of Passing Percentage
10th
12th
Graduation
Post Graduation
Reason for Gap if any ( (Education and work experience )
Preferred Location
Current Location
Have you taken any Interview with I-Flex in the last 6 months??? (Yes /
No)
Date of birth
Kesar
Pride Consultants
Ph# (022) 40261778/9819120072
Mail: kesar@prideconsultants.net
————
Opening in Yash Technology Pune
- Experience in Java, J2ee, Hibernate, Spring, Ajax,, Struts, UML, Rational Rose technologies
- Atleast 3 yr of relevant experience in technologies mentioned above and team handling experience for Team Lead Positions
- Good oral and written communication skills
Opportunities with YASH :
- Compensation above the industry standards.
- To work on high-end and latest technologies, in development areas mainly.
- To work directly with a reputed client at Magarpatta City Pune
- Deserving candidates would get an opportunity to work at client locations in
US through H1B Visa Sponsorship
- Excellent work culture.
For more details visit www.yash.com
Professionals having cutting edge on technology & with a fire to excel are invited to join our work force with finest exposure to technology, compensation & work culture.
If interested please forward your latest resume and contact numbers along with details like:
Current CTC:
Expected CTC:
Joining time required:
Willing to relocate:
To renu.vaishya@yash.com to discuss more.
Renu Vaishya
Sr. Executive-HR
Yash Technologies Pvt Ltd.,
A Wing, Level 6, Tower 10,
Magarpatta City, Pune.
————-
Opening in On Mobile Bangalore
Location: Bangalore
Exp: 3 to 6 yrs
Role: SSE
Job de! scription:
Role & Responsibility
Assisting and Guiding the team members across different development stages and when team members face any Technical or Business problems.
Primarily responsible for any architectural definitions and / or major design elements of the project
Selecting , Validating & Ensuring the technology choices across the different development stages.
Ability to be hands on when required especially troubleshooting technical and deployment issues.
Thorough and Excellent understanding of the overall architecture and technical objectives of the project
Mandatory skills
Possess an extremely sound understanding of ar! eas in C omputer Science such as Algorithms, Object Oriented Design and Operating Systems.
• Core Java with strong Multithreading experience
• SQL
• Preferably with good software Product development exposure
Other Skills:
!
JDBC, XML, JSP and Servlets
Experience : 3 to 6 years
Qualification : BE/BTech /ME /MTech/MCA
If you are interested working with OnMobile and if your profile matches with the requirement… then please send us your updated resume as a reply to this mail with the following details
CTC:
Ex CTC:
Notice Period:
Piyush Singh
Vati Consulting Pvt. Ltd.
III Floor, Sadath Court |5/6, Magrath Road |Bangalore-560025.
www.vaticonsulting.com
E: piyush@vaticonsulting.com
Mob: 09916140577
—————
Opening in Aztec Software.
Company Name : Aztec Software
Job Location : Bangalore
Education : BE / B. TECH / BCA / B.Sc(Computer) / M.Sc (comp) / ME / M.TECH
/ MCA / MBA
Experience : 3 to 5 yrs
SKILLS REQUIRED
Primary Skills : Core Java,J2EE, Hibernate, Apache, Jboss, EJB, JMS, JSP, I18N and L10N
// kindly forward this mail to your friends or Ur colleague, if someone is looking for a change //
Please send your latest CV to us ASAP & please update us with the following-
1. Total Exp.:
2. Skill Exp:
3. Current CTC:
4. Expected CTC:
5. D.O.B.:
6. Passport NO:
7. Educational Qualification:
8. Joining Time:
9. Current Location:
10. Current Orgnazation:
11. Ready to work 24 x 7
020-40004632 or deepanjan@pathfinder.net.in
Thanks & Regards
Deepanjan Chakraborty
Cell N0. 0-9881713015
———————
Opening in Capgemini Bangalore
Junior Developer - Knowledge in most of the following is must
§ Spring MVC, Hibernate (atleast 1+ years) Oracle
§ Java, Servlets, JSP, XML (atleast 2+ years) Junit Code review skills Communication skills
§ Analyzing requirements and problem solving skills
§ Experience in SDLC and/or application support project
§ Must have proven experience in real life projectRole: The role of the individual will be that of a Developer in J2EE application and will work with Technical leaders within the PDM group.
And
Designer / Developer - Skill Set
Knowledge in most of the following is must
§ Spring MVC, Hibernate (atleast 2 years) AOP, Oracle (atleast 4+ years)
§ Java, Servlets, JSP, XML (atleast 4+ years) Design Patterns Web Services Junit
§ Code review skills ,Communication skills (Need to interact with partners and key users)
§ Analyzing requirements and problem solving skills Experience in SDLC and/or application support project PDM / PLM domain knowledge. Must have proven experience in real life project Role: The role of the individual will be that of a Designer/ Developer in J2EE application and will work with Technical leaders within the PDM group.
Work Location – Bangalore
If you are looking out for Exciting and Challenging career along with Learning and Growth kindly forward your resume to vaibhav.mule@capgemini.com
Pls Mention Current Loc & Skill in the Subject
Current CTC :
Total Experience :
Rel Experience :
Interviewed earlier by Capgemini ? If YES : when? where?
Vaibhav Mule | Capgemini Consulting India Pvt Ltd | Mumbai
Direct : +91 22 67557895 | Cell:+91 98332 27203
vaibhav.mule@capgemini.com
Join the Collaborative Business Experience
Visit www.capgemini.com
————–
Opening with ACS
About Our Company:
Advance Computer Services Limited (ACS) is an IT Services Company since 1976 and has pioneered Data Processing Centers in India based on IBM Mainframes. ACS was one of the first companies to import IBM Mainframes and AS/400 Systems in India. ACS is a registered STPI unit (Software Technology Parks of India) with 100% Export Oriented Unit (EOU) Status. ACS has its Solution Delivery Center at Mhape; Navi Mumbai spread over 15,000 square feet with additional facilities in Worli, Mumbai and branch offices in Bangalore, Pune and Delhi.
ACS has presence in the USA as ACS International Resources, Inc. (ACSIR) and is an INC. 500 HALL OF FAME Company (FIVE time listing in the prestigious INC. 500 magazine, including four consecutive times, as one of the fastest growing company in the US).
ACS is currently working on long term, exciting, multiple product development projects for its US and Indian clients with worldwide locations. As part of our expansion operations, we need the following for one of our leading software clients.
Primary Skill: Java, J2EE, webservices, Spring/hibernate/struts
Relevant Experience required: Total 2-4yrs
Location: MNC(on payrolls of Advance Computer Services),Pune
Kindly provide the following information with your word CV to process your profile.
• Total IT experience:
• Earliest Joining Time if Selected:
• Current Gross & Net Salary (monthly take home):
• Expected Gross & Net Salary:
• Passport No & Validity:
• Visa Status, if any:
• Date of Birth:
• Present Employer
• Current Designation:
• Direct/Contract Employee:
• Employee ID No.
• Official E mail ID:
• Reason for change of job:
• Current Resident of:
• Permanent Resident of
• Marital Status:
• Contact Detail: Cell: Resident: Office (with EXT):
• Willing to relocate:
• Also feel free to forward this mail to your friends and colleague with similar profile.
• Candidates willing to join in within 10-15 Days can apply.
Richa Mishra
Advance Computer Services
Unit # 201 to 204,Building No.5,Sector 2
Millennium Business Park,Mhape
Navi Mumbai-400 709,Maharashtra,India
E-ID :richam@asclimited.com
Phone :+91-22-27782805/06/40322800
Fax :+91 2227781540
Web : www.acs-intl.com;www.acslimited.com
Q. Why String class is immutable in java?
July 1st, 2008By immutable means, once String object is instantiated its value cannot be changed, even if we try to change its value java creates another instance of String but does not change thr original value. The answer why it is immutable is that java maintains the pool of string constants in memory. Whenever we create String object java creates the string object in heap and second it stores the reference of that object in string pool memory. So before creating a new string object in heap jvm checks if any reference of same string literal exists in heap if so it doesnt creates the new object in heap it just assigns the existing object reference. So if String is made muttable then it may be possible that other String reference to the same object exists and it will create code buggy.
Q. Which classes in java api has all methods static?
July 1st, 2008java.lang.Math, java.lang.System, java.util.Arrays,java.util.Collections
Q. why print() method is overloaded in PrintStream?
July 1st, 2008In printStream the print() method is overloaded so that it supports both objects and primitives. Also print(String x) and print(Object x) is provide, the question is why print(String x) when print(Object x) exists. The answer lies in internal implementaion of both methods. In case of Object the pring method do x.toString() to print the object if x is not null, in case of String the call to x.toString() will do the same thing as x. So for performace improvement both print methods are provided.