OOP in JAVA Quiz Questions

OBJECT ORIENTED PROGRAMMING WITH JAVA

Question: Can a private method of a super-class be declared within a subclass?

Question: Why Java does not support multiple inheritance ?

Question:What is the difference between final, finally and finalize?

Question: Where and how can you use a private constructor?

Question: In System.out.println(),what is System,out and println,pls explain?

Question: What is meant by "Abstract Interface"?

Question: Can you make an instance of an abstract class? For example - java.util.Calender is an abstract class with a method getInstance() which returns an instance of the Calender class.

Question: What is the output of x<y? a:b = p*q when x=1,y=2,p=3,q=4?

Question: What is the difference between Swing and AWT components?

Question: Why Java does not support pointers?

Question: What is a platform?

Question: What is the main difference between Java platform and other platforms?

Question: What is the Java Virtual Machine?

Question: What is the Java API?

Question: What is the package?

Question: What is native code?

Question:  Is Java code slower than native code?

Question: What is the serialization?

Question: How to make a class or a bean serializable?

Question:  Which containers use a border layout as their default layout?

Question:  What is synchronization and why is it important?

Question: What are synchronized methods and synchronized statements?

Question:  What is synchronization and why is it important?

Question: What are synchronized methods and synchronized statements?

Question: What are three ways in which a thread can enter the waiting state?

Question: Can a lock be acquired on a class?

Question: What's new with the stop(), suspend() and resume() methods in JDK 1.2?

Question: What is the preferred size of a component?

Question: What method is used to specify a container's layout?

Question: Which containers use a Flow-layout as their default layout?

Question: What is thread?

Question: What is multi threading?

Question: How does multi threading take place on a computer with a single CPU?

Question: How to create multithread in a program?

Question: Can Java object be locked down for exclusive use by a given thread?

Question: Can each Java object keep track of all the threads that want to exclusively access to it?

Question: What state does a thread enter when it terminates its processing?

Question: What invokes a thread's run() method?

Question: What is the purpose of the wait(), notify(), and notifyAll() methods?

Question: What are the high-level thread states?

Question: What is the Collections API?

Question: What is the List interface?

Question:  How does Java handle integer overflows and under-flows?

Question:  What is the Vector class?

Question: If a method is declared as protected, where may the method be accessed?

Question:  What is an Iterator interface?

Question: How many bits are used to represent Unicode, ASCII, UTF-16, and UTF-8 characters?

Question:  What is the difference between yielding and sleeping?

Question:  Is sizeof a keyword?

Question: What are wrapped classes?

Question: Does garbage collection guarantee that a program will not run out of memory?

Question: What is the difference between preemptive scheduling and time slicing?

Question: Name Component subclasses that support painting.

Question: What is a native method?

Question: How can you write a loop indefinitely?

Question:  Can an anonymous class be declared as implementing an interface and extending a class?

Question: What is the purpose of finalization?

Question: Which class is the super-class for every class.

Question: What is the difference between the Boolean & operator and the && operator?

Question: What is the GregorianCalendar class?

Question: What is the SimpleTimeZone class?

Question: Which Container method is used to cause a container to be laid out and redisplayed?

Question: What is the Properties class?

Question: What is the purpose of the Runtime class?

Question:  What is the purpose of the System class?

Question: What is the purpose of the finally clause of a try- catch-finally statement?

Question: What is the Locale class?

Question: What must a class do to implement an interface?

Question: What is an abstract method?

Question: What is a static method?

Question: What is a protected method?

Question: What is the difference between a static and a non -static inner class?

Question:  What is an object's lock and which object's have locks?

Question: When can an object reference be cast to an interface reference?

Question:  What is the difference between a Window and a Frame?

Question: What do heavy weight components mean?

Question: Which package has light weight components?

Question: What are peerless components?

Question: What is the difference between the Font and FontMetrics classes?

Question: What happens when a thread cannot acquire a lock on an object?

Question: What is the difference between the Reader/Writer class hierarchy and the InputStream/OutputStream class hierarchy?

Question: What classes of exceptions may be caught by a catch clause?

Question:What is the difference between throw and throws keywords?

Question: If a class is declared without any access modifiers, where may the class be accessed?

Question: What is the Map interface?

Question: Does a class inherit the constructors of its superclass?

Question: Name primitive Java types.

Question: Which class should you use to obtain design information about an object?

Question: How can a GUI component handle its own events?

Question: How are the elements of a GridBagLayout organized?

Question: What advantage do Java's layout managers provide over traditional windowing systems?

Question: What are the problems faced by Java programmers who don't use layout managers?

Question: What is the difference between static and non -static variables?

Question: What is the difference between the paint() and repaint() methods?

Question:  What is the purpose of the File class?

Question:  What restrictions are placed on method overloading?

Question:  What restrictions are placed on method overriding?

Question: What is casting?

Question: Name Container classes.

Question: What class allows you to read objects directly from a stream?

Question:  How are this() and super() used with constructors?

Question: How is it possible for two String objects with identical values not to be equal under the == operator?

Question: What an I/O filter?

Question: What is the Set interface?

Question:  What is the List interface?

Question: What is the purpose of the enableEvents() method?

Question: What is the difference between the File and RandomAccessFile classes?

Question: What interface must an object implement before it can be written to a stream as an object?

Question: What is the ResourceBundle class?

Question: What is the difference between a Scrollbar and a ScrollPane? Answer: A Scrollbar is a Component, but not a Container. A ScrollPane is a Container. A ScrollPane handles its own events and performs its own scrolling.

Question: What is a Java package and how is it used?

Question: What are the Object and Class classes used for?

Question: What is Serialization and deserialization?

Question: what is tunnelling?

Question: Does the code in finally block get executed if there is an exception and a return statement in a catch block?

Question: How you restrict a user to cut and paste from the html page?

Question:  Is Java a super set of JavaScript?

Question: What is a Container in a GUI?

Question: How the object oriented approach helps us keep complexity of software development under control?

Question: What is polymorphism?

Question: What is design by contract?

Question: What are use cases?

Question: What is the difference between interface and abstract class?

Question: What is an Iterator interface?

Question: What is the difference between the >> and >>> operators?

Question: Which method of the Component class is used to set the position and size of a component?

Question: How many bits are used to represent Unicode, ASCII, UTF-16, and UTF-8 characters?

Question: What is the difference between yielding and sleeping?

Question: Which java.util classes and interfaces support event handling?

Question: Is sizeof a keyword?

Question: What are wrapped classes?

Question: Does garbage collection guarantee that a program will not run out of memory?

Question: What restrictions are placed on the location of a package statement within a source code file?

Question: Can an object's finalize() method be invoked while it is reachable?

Question: What is the immediate superclass of the Applet class?

Question: What is the difference between preemptive scheduling and time slicing?

Question: Name three Component subclasses that support painting.

Question: What value does readLine() return when it has reached the end of a file?

Question: What is the immediate superclass of the Dialog class?

Question: What is clipping?

Question: What is a native method?

Question: Can a for statement loop indefinitely?

Question: What are order of precedence and associativity, and how are they used?

Question: When a thread blocks on I/O, what state does it enter?

Question: To what value is a variable of the String type automatically initialized?

Question: What is the catch or declare rule for method declarations?

Question: What is the difference between a MenuItem and a CheckboxMenuItem?

Question: What is a task's priority and how is it used in scheduling?

Question: What class is the top of the AWT event hierarchy?

Question: When a thread is created and started, what is its initial state?

Question: Can an anonymous class be declared as implementing an interface and extending a class?

Question: What is the range of the short type?

Question: What is the range of the char type?

Question: In which package are most of the AWT events that support the event-delegation model defined?

Question: What is the immediate superclass of Menu?

Question: What is the purpose of finalization?

Question: Which class is the immediate superclass of the MenuComponent class.

Question: What invokes a thread's run() method?

Question: What is the difference between the Boolean & operator and the && operator?

Question: Name three subclasses of the Component class.

Question: What is the GregorianCalendar class?

Question: Which Container method is used to cause a container to be laid out and redisplayed?

Question: What is the purpose of the Runtime class?

Question: How many times may an object's finalize() method be invoked by the garbage collector?

Question: What is the purpose of the finally clause of a try-catch-finally statement?

Question: What is the argument type of a program's main() method?

Question: Which Java operator is right associative?

Question: What is the Locale class?

Question: Can a double value be cast to a byte?

Question: What is the difference between a break statement and a continue statement?

Question: What must a class do to implement an interface?

Question: What method is invoked to cause an object to begin executing as a separate thread?

Question: Name two subclasses of the TextComponent class.

Question: What is the advantage of the event-delegation model over the earlier event-inheritance model?

Question: Which containers may have a MenuBar?

Question: How are commas used in the intialization and iterationparts of a for statement?

Question: What is the purpose of the wait(), notify(), and notifyAll() methods?

Question: What is an abstract method?

Question: How are Java source code files named?

Question: What is the relationship between the Canvas class and the Graphics class?

Question: What are the high-level thread states?

Question: What value does read() return when it has reached the end of a file?

Question: Can a Byte object be cast to a double value?

Question: What is the difference between a static and a non-static inner class?

Question: What is the difference between the String and StringBuffer classes

Question: If a variable is declared as private, where may the variable be accessed?

Question: What is an object's lock and which object's have locks?

Question: What is the Dictionary class?

Question: How are the elements of a BorderLayout organized?

Question: What is the % operator?

Question: When can an object reference be cast to an interface reference?

Question: What is the difference between a Window and a Frame?

Question: Which class is extended by all other classes?

Question: Can an object be garbage collected while it is still reachable?

Question: Is the ternary operator written x : y ? z or x ? y : z ?

Question: What is the difference between the Font and FontMetrics classes?

Question: How is rounding performed under integer division?

Question: What happens when a thread cannot acquire a lock on an object?

Question: What is the difference between the Reader/Writer class hierarchy and the InputStream/OutputStream class hierarchy?

Question: What classes of exceptions may be caught by a catch clause?

Question: If a class is declared without any access modifiers, where may the class be accessed?

Question: What is the SimpleTimeZone class?

Question: What is the Map interface?

Question: Does a class inherit the constructors of its superclass?

Question: For which statements does it make sense to use a label?

Question: What is the purpose of the System class?

Question: Which TextComponent method is used to set a TextComponent to the read-only state?

Question: How are the elements of a CardLayout organized?

Question: Is &&= a valid Java operator

Question: Name the eight primitive Java types.

Question: Which class should you use to obtain design information about an object?

Question: What is the relationship between clipping and repainting?

Question: Is "abc" a primitive value?

Question: What is the relationship between an event-listener interface and an event-adapter class?

Question: What restrictions are placed on the values of each case of a switch statement?

Question: What modifiers may be used with an interface declaration?

Question: Is a class a subclass of itself?

Question: What is the highest-level event class of the event-delegation model?

Question: What event results from the clicking of a button?

Question: How can a GUI component handle its own events?

Question: What is the difference between a while statement and a dostatement?

Question: How are the elements of a GridBagLayout organized?

Question: What advantage do Java's layout managers provide over traditional windowing systems?

Question: What is the Collection interface?

Question: What modifiers can be used with a local inner class?

Question: What is the difference between static and non-static variables?

Question: What is the difference between the paint() and repaint() methods?

Question: What is the purpose of the File class?

Question: Can an exception be rethrown?

Question: Which Math method is used to calculate the absolute value of a number?

Question: How does multithreading take place on a computer with a single CPU?

Question: When does the compiler supply a default constructor for a class?

Question: When is the finally clause of a try-catch-finally statement executed?

Question: Which class is the immediate superclass of the Container class?

Question: If a method is declared as protected, where may the method be accessed?

Question: How can the Checkbox class be used to create a radio button?.

Question: Which non-Unicode letter characters may be used as the first character of an identifier?

Question: What restrictions are placed on method overloading?

Question: What happens when you invoke a thread's interrupt method while it is sleeping or waiting?

Question: What is casting?

Question: What is the return type of a program's main() method?

Question: Name four Container classes.

Question: What is the difference between a Choice and a List?

Question: What class of exceptions are generated by the Java run-time system?

Question: What class allows you to read objects directly from a stream?

Question: What is the difference between a field variable and a local variable?

Question: Under what conditions is an object's finalize() method invoked by the garbage collector?

Question: How are this() and super() used with constructors?

Question: What is the relationship between a method's throws clause and the exceptions that can be thrown during the method's execution?

Question: What is the difference between the JDK 1.02 event model and the event-delegation model introduced with JDK 1.1?

Question: How is it possible for two String objects with identical values not to be equal under the == operator?

Question: Why are the methods of the Math class static?

Question: What Checkbox method allows you to tell if a Checkbox is checked?

Question: What state is a thread in when it is executing?

Question: What are the legal operands of the instance of operator?

Question: How are the elements of a GridLayout organized?

Question: What an I/O filter?

Question: If an object is garbage collected, can it become reachable again?

Question: What is the Set interface?

Question: What classes of exceptions may be thrown by a throw statement?

Question: What are E and PI?

Question: Are true and false keywords?

Question: What is a void return type?

Question: What is the purpose of the enableEvents() method?

Question: What is the difference between the File and RandomAccessFile classes?

Question: What happens when you add a double value to a String?

Question: What is your platform's default character encoding?

Question: Which package is always imported by default?

Question: What interface must an object implement before it can be written to a stream as an object?

Question: How are this and super used?

Question: What is the purpose of garbage collection?

Question: What is a compilation unit?

Question: What interface is extended by AWT event listeners?

Question: What restrictions are placed on method overriding?

Question: How can a dead thread be restarted?

Question: What happens if an exception is not caught?

Question: What is a layout manager?

Question: Which arithmetic operations can result in the throwing of an ArithmeticException?

Question: What are three ways in which a thread can enter the waiting state?

Question: Can an abstract class be final?

Question: What is the ResourceBundle class?

Question: What happens if a try-catch-finally statement does not have a catch clause to handle an exception that is thrown within the body of the try statement?

Question: What is numeric promotion?

Question: What is the difference between a Scrollbar and a ScrollPane?

Question: What is the difference between a public and a non-public class?

Question: To what value is a variable of the boolean type automatically initialized?

Question: Can try statements be nested?

Question: What is the difference between the prefix and postfix forms of the ++ operator?

Question: What is the purpose of a statement block?

Question: What is a Java package and how is it used?

Question: What modifiers may be used with a top-level class?

Question: What are the Object and Class classes used for?

Question: How does a try statement determine which catch clause should be used to handle an exception?

Question: Can an unreachable object become reachable again?

Question: When is an object subject to garbage collection?

Question: What method must be implemented by all threads?

Question: What methods are used to get and set the text label displayed by a Button object?

Question: Which Component subclass is used for drawing and painting?

Question: What are synchronized methods and synchronized statements?

Question: What are the two basic ways in which classes that can be run as threads may be defined?

Question: What are the problems faced by Java programmers who don't use layout managers?

Question: What is the difference between an if statement and a switch statement?

Question: What happens when you add a double value to a String?

Question: What is the List interface?

Question: Why do we need public static void main(String args[]) method in

Question: What is the difference between an Interface and an Abstract class

Question: Explain serialization

Question: What are the rules of serialization

Question: What is difference between error and exception

Question: What do you mean by object oreiented programming

Question: What are 4 pillars of object oreinted programming

Question: Difference between procedural and object oreinted language

Question: What is the difference between constructor and method

Question: What is the difference between parameters and arguments

Question: What is reflection in java