Interview Questions and Answers for 'C' | Search Interview Question

Interview Questions and Answers - Order By Newest

Q721. Can we add heterogeneous elements into TreeMap ?

Ans. No, Sorted collections don't allow addition of heterogeneous elements as they are not comparable.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve java collections comparable interface treemap}

Q722. Will it create any problem if We add elements with key as user defined object into the TreeMap ?

Ans. It won't create any problem if the objects are comparable i.e we have that class implementing Comparable interface.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve java collections treemap comparable interface}

Q723. Can we have null keys in TreeMap ?

Core Java

Ans. No, results in exception.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve java collections treemap Asked in 6 Companies Basic frequent}

Q724. Can value be null in TreeMap ?

Core Java

Ans. Yes.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve java collections treemap yes-no}

Q725. Which interface TreeMap implements ?

Ans. TreeMap implements NavigableMap, SortedMap, Serializable and Clonable.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve java collections treemap}

Frequently asked in Phone Interviews.

Q726. What the Bean scopes provided by Spring ?

Spring

Ans. Singleton , Prototype , Request , Session , global-session

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve spring framework bean scope general electric ge}

Frequently asked in Phone Interviews.

Q727. What are the various Auto Wiring types in Spring ?

Ans. By Name , By Type and Constructor.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve java spring spring container dependency injection auto wiring auto wiring types general electric ge}

Q728. What are the the methods to clear cache in Hibernate ?

Hibernate

Ans. Evict() and clear(). Evist is used to clear a particular object from the cache whereas clear clears the complete local cache.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve hibernate orm hibernate cache}

Q729. What are different types of second level cache ?

Hibernate

Ans. 1. EHCache ( Easy Hibernate )
2. OSCache ( Open Symphony )
3. Swarm Cache ( JBoss )
4. Tree Cache ( JBoss )

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve hibernate orm hibernate cache technical lead Asked in 7 Companies}

Q730. Can we disable first level cache ? What should one do if we don't want an object to be cached ?

Hibernate

Ans. No.We can either call evict after the object retrieval or can use separate sessions.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve hibernate orm hibernate cache architecture}

Q731. What is Hibernate ?

Hibernate

Ans. Hibernate is a Java ORM Framework.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve hibernate orm frameworks architecture}

Q732. What are the different types of inheritance in Hibernate ?

Hibernate

Ans. Table Per Class , Table per Sub Class , Table per Concrete Class

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve hibernate orm inheritance hibernate Asked in 1 Companies Basic frequent}

Q733. What is lazy fetching in Hibernate ?

Hibernate

Ans. Lazy fetching is the technique of not loading the child objects when parent objects are loaded. By default Hibernate does not load child objects. One can specify whether to load them or not while doing the association.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve hibernate lazy fetching architecture Asked in 11 Companies frequent}

Try 2 Question(s) Test

Q734. Is It Good to use Reflection in an application ? Why ?

Core Java

Ans. no, It's like challenging the design of application.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve java reflection api yes-no architecture Asked in 1 Companies intermediate}

Q735. Why is Reflection slower ?

Ans. Because it has to inspect the metadata in the bytecode instead of just using precompiled addresses and constants.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve java reflection reflection api architecture}

Q736. When should we use prototype scope and singleton scope for beans ?

Spring

Ans. We should use singleton scope for beans when they are stateless and prototype when they are stateful.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve spring bean scope general electric ge singleton}

Q737. Difference between Assert and Verify ?

Testing

Ans. Assert works only if assertions ( -ea ) are enabled which is not required for Verify.Assert throws an exception and hence doesn't continue with the test if assert evaluates to false whereas it's not so with Verify.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve assert junit mockito verify testing unit testing Asked in 5 Companies}

Q738. How many SessionFactory and Session objects are created ?

Java EE

Ans. Single SessionFactory object and multiple session objects for opening different session. Hibernate creates new Session object per thread.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve hibernate sessionfactory hibernate session hibernate}

Q739. What is the use of hbm2ddl Configuration in Hibernate ?

Hibernate

Ans. This configuration specifies if hibernate should creates the Schema / Table on its own if the respective table is not found.

"update" doesn't create the table if it's not found whereas configuration set as "create" creates the schema automatically.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve hibernate hibernate configuration hibernate.cfg.xml hbm2ddl}

Q740. What are the different ID generating strategies using @GeneratedValue annotation ?

Hibernate

Ans. Auto , Identity , Sequence and Table.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve hibernate generatedvalue annotations architecture}

Q741. How to do Eager loading in Hibernate ?

Hibernate

Ans. Using

lazy = false in hibernate config file

or

@Basic(fetch=FetchType.EAGER) at the mapping

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve hibernate lazy loading hibernate basic annotation hibernate architecture}

Q742. What is cascade ?

Hibernate

Ans. Instead of Saving Parent as well as Child Entities individually , Hibernate provides the option to persist / delete the related entities when the Parent is persisted.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve hibernate cascade hibernate relationship hibernate associations}

Q743. What are the different Cascade types ?

Hibernate

Ans. Detach, Merge , Persist , Remove , Refresh

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve hibernate cascade cascade type}

Q744. Which type of associated Entities are Eagerly loaded by Default ?

Hibernate

Ans. OneToOne

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve hibernate hibernate associations hibernate relationship}

Q745. Can we declare Entity class as final ?

Hibernate

Ans. Yes but as Hibernate creates the Proxy Classes inherited from the Entity Classes to communicate with Database for lazy initialization. Declaring entity classes as final will prohibit communication with database lazily and hence will be a performance hit.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve hibernate proxy objects proxy classes entity hibernate}

Q746. What is the difference between int[] x; and int x[]; ?

Core Java

Ans. No Difference. Both are the acceptable ways to declare an array.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve java array arrays array declaration difference between Asked in 3 Companies basic}

Q747. What is asynchronous I/O ?

Ans. It is a form of Input Output processing that permits other processing to continue before the I/O transmission has finished.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve java io file fileio java7 architecture}

Frequently asked these days as there are major changes in Java 8.

Q748. What are new features introduced with Java 8 ?

Core Java

Ans. Lambda Expressions , Interface Default and Static Methods , Method Reference , Parameters Name , Optional , Streams, Concurrency.

Sample Code for Lambda

Sample Code for interface default

Sample Code for Optional

Sample Code for Streams

Sample Code for java.time

Sample Code for Predicate

Sample Code for Consumer

Sample Code for MapMerge

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve java java8 technical lead technical architect Asked in 14 Companies expert frequent}

Rarely asked as default methods have been introduced with Java 8.

Q749. Can we have a default method without a Body ?

Core Java

Ans. No. Compiler will give error.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve java java8 default method yes-no rare}

Rarely asked as default methods have been introduced with Java 8.

Q750. Can we have a default method definition in the interface without specifying the keyword "default" ?

Core Java

Ans. No. Compiler complains that its an abstract method and hence shouldn't have the body.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve java java8 default methods default keyword yes-no}

Search Interview Questions

Help us and Others Improve. Please let us know the questions asked in any of your previous interview.