Sample Interview Questions For Core Java                                                        Other Questions

Dear Visitors herewith we are listing some smaple expected questions asked during Interview Sessions. This Questions is only for your references. Refer the suitable books and prepare the answers for this questions for your satisfaction.

Why Java is not 100% pure object oriented language? Explain working of Java Virtual Machine (JVM) why java does not support Multiple Inheritance? When we are sending the serialized array object thro the network, what is being passed ? is the value or the reference ? JVM is platform independent/dependent?why? 2) which one is faster in execution Array List or Array? why? When you have an object passed to a method and when the object is reassigned to a different one, then is the original reference lost What is heap in Java Can a method be static and synchronized Will there be a performance penalty if you make a method synchronized? If so, can you make any design changes to improve the performance What is MVC architecture What are interfaces? or How to support multiple inheritance in Java? Difference: Java Beans, Servlets Why java does not support Multiple Inheritance?Why java is not pure Object Oriented? What is the Difference between Design Pattern and Architecture? How an Hashtable can change the iterator? Can a HashMap change the iterator? What is phantom memory In Java, how are objects / values passed around What is EJB How would you implement a thread pool What design patterns have you used How to use C++ code in Java Program? Difference: AWT, Swing How do i upload a file from client side to server side using servlet and jsp this will happen when I click upload button on web-page? How can we take various inputs from user as int,char,string,float etc ? What are the different kinds of exceptions? How do you catch a Runtime exception Do primitive types have a class representation What are the differences between C++ and Java How does serialization work What are the differences between ArrayList and a Vector Difference between "APPLET" and "APPLICATION" Disadvantages of Java Explain the importance of "static"keyword It is a saying that static methods in JAVA programs should be minimised. What is the reason for this? any problems arise or there is any performance measures to be looked into it. Why multiple inheritance using classes is disadvantage in java What are the differences between JIT and HotSpot How all can you free memory How can you do multiple inheritance in Java How does garbage collection work How would you declare a SingleThreaded servlet What is the interface of thread? What is BYTE Code? Whether a Class,Method can be garbage collected or not?How? Give example of : High severity & Low priority Write a program that singleton objects returns two instances? What is a memory footprint? How can you specify the lower and upper limits of the RAM used by the JVM? What happens when the JVM needs more memory Does java do reference counting What is data encapsulation? What does it buy you What are the differences between AWT and Swing How are memory leaks possible in Java How can you swap two variables without using a third variable? Whether private,protected method can be overloaded,overrided or not? What do you meant by private constructor? why somebody declare only private constructor. Does JVM maintain a cache by itself? Does the JVM allocate objects in heap? Is this the OS heap or the heap maintained by the JVM? Why What does a static inner class mean? How is it different from any other static member How would you pass a java integer by reference to another function What are the differences between EJB and Java beans How can u move/drag a component placed in Swing Container? Does Java have "goto"? Why ArrayList is faster than Vector? Is java a fully object oriented programming or not? if not why? Whether we can set the time implicitly for the garbage collection? What are the disadvantages of reference counting in garbage collection How do you declare constant values in java What is reflection API? How are they implemented How would you keep track of a session What are STRUTS What is the purpose of interface? And tell the difference between the class and interface? What is the meaning of "final" keyword? Meaning - Abstract classes, abstract methods What is the basic difference between Java and .Net Write program for single objects returns two instances? Is it advisable to depend on finalize for all cleanups How all can you instantiate final members What is the primary advantage of XML driven Java Beans Explain the keywords - native, transient, volatile, finally Explain Servlet and JSP life cycle Can I create final executable from Java? Difference – Java, C++ What is the difference between an object and an instance? And give me a real time example to differentiate these two? When you use a struts framework, where would you place your business logic How is serialization implemented in Java What are the primitive types in Java Differences between HashList and HashMap, Set and List What would happen if you say this = null Explain Garbage collection mechanism in Java Explain Java security model How hashtable is synchronized?why hashmap is not synchronized?Can we make hashmap synchronized? Can we declare multiple main() methods in multiple classes.ie can we have each main method in its class in our program? Is there a separate stack for each thread in Java What is the sweep and paint algorithm What do you like most with Ant