Frequently Asked Questions - Java

Frequently Asked Questions -  Java

·         Can a main() method of class be invoked in another class?

·         What is the difference between java command line arguments and C command  line arguments?

·         What is the difference between == & .equals

·         What is the difference between abstract class & Interface.

·         What is singleton class & it's implementation.

·         Use of static, final variable

·         Examples of final class

·         Difference between Event propagation & Event delegation

·         Difference between Unicast & Multicast model

·         What is a java bean

·         What is synchronized keyword used for?

·         What are the restrictions of an applet & how to make the applet access the local machines resources.

·         What is reflect package used for & the methods of it.

·         What is serialization used for

·         Can methods be overloaded based on the return types?

·         Why do we need a finalze() method when Garbage Collection is there?

·         Difference between AWT and Swing components?

·         Is there any heavy weight component in Swings?

·         Can the Swing application if you upload in net, be compatible with your browser?

·         What should you do get your browser compatible with swing components?

·         What are the methods in Applet?

·         When is init(),start() called?

·         When you navigate from one applet to another what are the methods called?

·         What is the difference between Trusted and Untrusted Applet?

·         What is Exception?

·         What are the ways you can handle exception?

·         When is try, catch block used?

·         What is finally method in Exceptions?

·         What are the types of access modifiers?

·         What is protected and friendly?

·         What are the other modifiers?

·         Is synchronised modifier?

·         What is meant by polymorphism?

·         What is inheritance?

·         What is method Overloading? What is this in OOPS?

·         What is method Overriding? What is it in OOPS?

·         Does java support multi dimensional arrays?

·         Is multiple inheritance used in Java?

·         How do you send a message to the browser in JavaScript?

·         Does javascript support multidimensional arrays?

·         Is there any tool in java that can create reports?

·         What is meant by Java?

·         What is meant by a class?

·         What is meant by a method?

·         What are the OOPS concepts in Java?

·         What is meant by encapsulation? Explain with an example

·         What is meant by inheritance? Explain with an example

·         What is meant by polymorphism? Explain with an example

·         Is multiple inheritance allowed in Java? Why?

·         What is meant by Java interpreter?

·         What is meant by JVM?

·         What is a compilation unit?

·         What is meant by identifiers?

·         What are the different types of modifiers?

·         What are the access modifiers in Java?

·         What are the primitive data types in Java?

·         What is meant by a wrapper class?

·         What is meant by static variable and static method?

·         What is meant by Garbage collection?

·         What is meant by abstract class

·         What is meant by final class, methods and variables?

·         What is meant by interface?

·         What is meant by a resource leak?

·         What is the difference between interface and abstract class?

·         What is the difference between public private, protected and static

·         What is meant by method overloading?

·         What is meant by method overriding?

·         What is singleton class?

·         What is the difference between an array and a vector?

·         What is meant by constructor?

·         What is meant by casting?

·         What is the difference between final, finally and finalize?

·         What is meant by packages?

·         What are all the packages?

·         Name 2 calsses you have used?

·         Name 2 classes that can store arbitrary number of objects?

·         What is the difference between java.applet.* and java.applet.Applet?

·         What is a default package?

·         What is meant by a super class and how can you call a super class?

·         What is anonymous class?

·         Name interfaces without a method?

·         What is the use of an interface?

·         What is a serializable interface?

·         How to prevent field from serialization?

·         What is meant by exception?

·         How can you avoid the runtime exception?

·         What is the difference between throw and throws?

·         What is the use of finally?

·         Can multiple catch statements be used in exceptions?

·         Is it possible to write a try within a try statement?

·         What is the method to find if the object exited or not?

·         What is meant by a Thread?

·         What is meant by multi-threading?

·         What is the 2 way of creating a thread? Which is the best way and why?

·         What is the method to find if a thread is active or not?

·         What are the thread-to-thread communcation?

·         What is the difference between sleep and suspend?

·         Can thread become a member of another thread?

·         What is meant by deadlock?

·         How can you avoid a deadlock?

·         What are the three typs of priority?

·         What is the use of synchronizations?

·         Garbage collector thread belongs to which priority?

·         What is meant by time-slicing?

·         What is the use of 'this'?

·         How can you find the length and capacity of a string buffer?

·         How to compare two strings?

·         What are the interfaces defined by Java.lang?

·         What is the purpose of run-time class and system class

·         What is meant by Stream and Types?

·         What is the method used to clear the buffer?

·         What is meant by Stream Tokenizer?

·         What is serialization and de-serialisation?

·         What is meant by Applet?

·         How to find the host from which the Applet has originated?

·         What is the life cycle of an Applet?

·         How do you load an HTML page from an Applet?

·         What is meant by Applet Stub Interface?

·         What is meant by getCodeBase and getDocumentBase method?

·         How can you call an applet from a HTML file

·         What is meant by Applet Flickering?

·         What is the use of parameter tag?

·         What is audio clip Interface and what are all the methods in it?

·         What is the difference between getAppletInfo and getParameterInfo?

·         How to communicate between applet and an applet?

·         What is meant by event handling?

·         What are all the listeners in java and explain?

·         What is meant by an adapter class?

·         What are the types of mouse event listeners?

·         What are the types of methods in mouse listeners?

·         What is the difference between panel and frame?

·         What is the default layout of the panel and frame?

·         What is meant by controls and types?

·         What is the difference between a scroll bar and a scroll panel.

·         What is the difference between list and choice?

·         How to place a component on Windows?

·         What are the different types of Layouts?

·         What is meant by CardLayout?

·         What is the difference between GridLayout and GridBagLayout

·         What is the difference between menuitem and checkboxmenu item.

·         What is meant by vector class, dictionary class , hash table class,and property class?

·         Which class has no duplicate elements?

·         What is resource bundle?

·         What is an enumeration class?

·         What is meant by Swing?

·         What is the difference between AWT and Swing?

·         What is the difference between an applet and a Japplet

·         What are all the components used in Swing?

·         What is meant by tab pans?

·         What is the use of JTree?

·         How can you add and remove nodes in Jtree.

·         What is the method to expand and collapse nodes in a Jtree

·         What is the use of JTable?

·         What is meant by JFC?

·         What is the class in Swing to change the appearance of the Frame in Runtime.

·         How to reduce flicking in animation?

·         What is meant by Javabeans?

·         What is JAR file?

·         What is meant by manifest files?

·         What is Introspection?

·         What are the steps involved to create a bean?

·         Say any two properties in Beans?

·         What is persistence?

·         What is the use of beaninfo?

·         What are the interfaces you used in Beans?

·         What are the classes you used in Beans?

·         What is the diffrence between an Abstract class and Interface

·         What is user defined exception?

·         What do you know about the garbate collector?

·         What is the difference between C++ & Java?

·         How do you communicate in between Applets & Servlets?

·         What is the use of Servlets?

·         In an HTML form I have a Button which makes us to open another page in 15 seconds. How will do you that?

·         What is the difference between Process and Threads?

·         How will you initialize an Applet?

·         What is the order of method invocation in an Applet?

·         When is update method called?

·         How will you communicate between two Applets?

·         Have you ever used HashTable and Dictionary?

·         What are statements in JAVA?

·         What is JAR file?

·         What is JNI?

·         What is the base class for all swing components?

·         What is JFC?

·         What is Difference between AWT and Swing?

·         Considering notepad/IE or any other thing as process, What will Happen if you start notepad or IE 3 times? Where 3 processes are started or 3 threads are started?

·         How does thread synchronization occurs inside a monitor?

·         How will you call an Applet using a Java Script function?

·         Is there any tag in HTML to upload and download files?

·         Why do you Canvas?

·         How can you push data from an Applet to Servlet?

·         What are the benefits of Swing over AWT?

·         Where the CardLayout is used?

·         What is the Layout for ToolBar?

·         What is the difference between Grid and GridbagLayout?

·         How will you add panel to a Frame?

·         What is the corresponding Layout for Card in Swing?

·         What is light weight component?

·         What is bean? Where it can be used?

·         What is difference in between Java Class and Bean?

·         What is the mapping mechanism used by Java to identify IDL language?

·         Diff between Application and Applet?

·         What is serializable Interface?

·         What is the difference between CGI and Servlet?

·         What is the use of Interface?

·         Why Java is not fully objective oriented?

·         Why does not support multiple Inheritance?

·         What it the root class for all Java classes?

·         What is polymorphism?

·         Suppose If we have variable ' I ' in run method, If I can create one or  More thread each thread will occupy a separate copy or same variable will be shared?

·         What is Constructor and Virtual function? Can we call Virtual

·         Funciton in a constructor?

·         Why we use OOPS concepts? What is its advantage?

·         What is the difference in between C++ and Java? can u explain in detail?

·         What is the exact difference in between Unicast and Multicast object? Where we will use?

·         How do you sing an Applet?

·         In a Container there are 5 components. I want to display the all the components names, how will you do that one?

·         Why there are some null interface in java? What does it mean?

·         Give me some null interfaces in JAVA?

·         Tell me the latest versions in JAVA related areas?

·         What is meant by class loader? How many types are there? When will we use them?

·         What is meant by flickering?

·         What is meant by cookies? Explain?

·         Problem faced in your earlier project

·         How OOPS concept is achieved in Java

·         Features for using Java

·         How does Java 2.0 differ from Java 1.0

·         Public static void main - Explain

·         What are command line arguments

·         Explain about the three-tier model

·         Difference between String & StringBuffer

·         Wrapper class. Is String a Wrapper Class

·         What are the restriction for static method Purpose of the file class

·         Default modifier in Interface

·         Difference between Interface & Abstract class

·         Can abstract be declared as Final

·         Can we declare variables inside a method as Final Variables

·         What is the package concept and use of package

·         How can a dead thread be started

·         Difference between Applet & Application

·         Life cycle of the Applet

·         Can Applet have constructors

·         Difference between canvas class & graphics class

·         Explain about Superclass & subclass

·         What is AppletStub

·         Explain Stream Tokenizer

·         What is the difference between two types of threads

·         Checked & Unchecked exception

·         Use of throws exception

·         What is finally in exception handling  Vector class

·         What will happen to the Exception object after exception handling

·         Two types of multitasking

·         Two ways to create the thread

·         Synchronization

·         I/O Filter

·         Can applet in different page communicate with each other

·         Why Java is not 100 % pure OOPS? ( EcomServer )

·         When we will use an Interface and Abstract class?

·         How to communicate 2 threads each other?

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