Example & Tutorial understanding programming in easy ways.
What is garbage collection?
Read More →What do you understand by Synchronization?
Read More →What are different types of access modifiers?
Read More →When we can declare a method as abstract method ?
Read More →Java Virtual Machine (JVM)
Read More →Can abstract modifier be applied to a variable?
Read More →What is abstract class in java?
Read More →Can we define abstract class (as outer class) and class ( inner class) in java ?If Yes give an example .
Read More →How to define an Abstract class?
Read More →Why we define constructor in abstract class in java when we can't initialized it abstract class. Or how constructor of abstract class can used. Give an example
Read More →Can we define abstract class (as inner class) and class ( outer class) in java ?If Yes give an example?
Read More →Abstract method
Read More →Can we declare abstract method private ?
Read More →Can abstract methods synchronized?
Read More →What is interface?
Read More →How to define an Interface?
Read More →Can we create a interface within interface ?If Yes then give an example .How we can call inner interface?
Read More →Can we declare a enum within interface ?If Yes then give an example .How we can call enum ?
Read More →What is output of following ?explain why?
Read More →How many number of non-public class definitions can a source file have?
Read More →How many number of public class definitions can a source file have?
Read More →What happened If we compile and run following code?
Read More →What happens if parent is not serialized and child class are serialized?
Read More →What is OOPS(Object Oriented Programming)?
Read More →What is the difference between procedural and object-oriented programs?
Read More →What is the difference between Assignment and Initialization?
Read More →What is OOPS(Object-Oriented Programming) principle?
Read More →What is encapsulation principle?
Read More →Explain the Inheritance principle.
Read More →Explain the Polymorphism principle.
Read More →Explain the different forms of Polymorphism.
Read More →What are Class, Constructor and Primitive data types?
Read More →What is an Object and how do you allocate memory to it?
Read More →What is the difference between constructor and method?
Read More →What are methods and how are they defined?
Read More →What is the use of bin and lib in JDK?
Read More →What is casting?
Read More →How many ways can an argument be passed to a subroutine and explain them?
Read More →What is the difference between an argument and a parameter?
Read More →What are Access Specifiers available in Java?
Read More →Describe the wrapper classes in Java.
Read More →What is the class variables ?
Read More →Why there are no global variables in Java?
Read More →What is the difference between class variable, member variable and automatic(local) variable
Read More →When are static and non static variables of the class initialized?
Read More →When are automatic variable initialized?
Read More →What is method Overriding?
Read More →What restrictions are placed on method overriding?
Read More →What is Method overloading?
Read More →What restrictions are placed on method overloading?
Read More →What is the difference between Overloading and Overriding?
Read More →Can overriding methods have different return types?
Read More →Can constructors be overloaded?
Read More →If you use super() or this() in a constructor where you us it in the constructor?
Read More →What is difference between ArrayList and vector?
Read More →What is difference between HashMap and HashTable?
Read More →What is difference between Arrays and ArrayList ?
Read More →What is difference between HashMap and HashTable?
Read More →What is difference between Arrays and ArrayList ?
Read More →Describe the feature of try-with-resorce feature of jdk 1.7?
Read More →What is difference between List and Set?
Read More →When to use ArrayList or LinkedList?
Read More →What is difference between iterator access and index access?
Read More →Which all classes implement Set interface?
Read More →Where you use List and where ArrayList?
Read More →If an ArrayList has to be iterate to read data only, what are the possible ways and which is the fastest?
Read More →What are the classes implementing List interface?
Read More →if accessing through iterator is slow then why do we need it and when to use it?
Read More →Which design pattern Iterator follows?
Read More →How to sort list in reverse order?
Read More →Can a null element added to a Treeset or HashSet?
Read More →How to sort list of strings - case insensitive?
Read More →How to make a List (ArrayList,Vector,LinkedList) read only?
Read More →How can Arraylist be synchronized?
Read More →How we can sort any class on the behalf of the properties of collection. Like we has a collection of named Employee objects we need shortlist by using Employee ID.
Read More →What is ConcurrentHashMap?
Read More →Which is faster to iterate LinkedHashSet or LinkedList?
Read More →Which data structure HashSet implements?
Read More →Arrange in the order of speed - HashMap,HashTable, Collections.synchronizedMap,concurrentHashmap?
Read More →What is the use of Dimond operator feature of java7?
Read More →What is IdentityHashMap?
Read More →What is WeakHashMap?
Read More →What is an exception?
Read More →Which is superclass of Exception?
Read More →What is Exception and Error ?
Read More →What is exception handling?
Read More →What is a Thread ?
Read More →Collection framework in java interview questions
Read More →What is the difference between thread and process?
Read More →1. What is OOPS?
Read More →1. What is OOPS?
Read More →2. Write basic concepts of OOPS?
Read More →How do you implement Thread in Java?
Read More →When to use Runable and Thread in java?
Read More →What is the difference between start() and run() method of thread class
Read More →Difference between Runnable and Callable in Java?
Read More →3. What is Encapsulation?
Read More →4. What is Polymorphism?
Read More →5. What is Inheritance?
Read More →6. What is multiple inheritance and does java support?
Read More →7. What is an abstraction?
Read More →What is thread-safety?
Read More →Whar is race condition in multi-threading in java?
Read More →8.What is the difference between abstraction and encapsulation?
Read More →What is Executors Framework ?
Read More →How to stop thread in Java?
Read More →9. what is the use of super keyword
Read More →What happens when an Exception occurs in a thread?
Read More →10.what is the Advantage of OOPs over Procedure-oriented programming language
Read More →Why wait, notify and notifyAll are not inside thread class?
Read More →What is ThreadLocal variable in Java?
Read More →11.What is final variable and Use of final variable
Read More →You have thread T1, T2 and T3, how will you ensure that thread T2 run after T1 and thread T3 run after T2?
Read More →What does yield() method of Thread class do?
Read More →Difference between submit() and execute() method thread pool in Java?
Read More →What are the different states of a thread\'s lifecycle?
Read More →What is use of synchronized keyword?
Read More →12.What is final class - Using final to prevent inheritance?.
Read More →13.what is final Method.
Read More →14.what is the use of final keyword with Variables?
Read More →You have thread T1, T2 and T3, how will you ensure that thread T2 run after T1 and thread T3 run after T2?
Read More →15.point to be remember keyword final.
Read More →What is Serialization? given an example.
Read More →17.Can you create a program without main method ?.
Read More →what is use of serialization in java?
Read More →why serialization in java?
Read More →how to serialization in java?
Read More →what is the 6 usage of this keyword in java?.
Read More →16.what is Runtime polymorphism or Dynamic Method Dispatch
Read More →What is a Serial Version UID (serialVersionUID) and why should I use it?
Read More →why serialversionuid is required?
Read More →How many methods in the Serializable interface?
Read More →what is the difference between serializable and externalizable interface in java?
Read More →What is the difference between static and dynamic binding ?
Read More →Can we override the static method?
Read More →What are the advantages or usage of threads?
Read More →What is operator overloading?
Read More →Why Multiple Inheritance is Not Supported in Java?
Read More →How downcasting is possible in java?
Read More →What is function overloading?
Read More →When to use private constructors in Java?
Read More →what is transient variables in java with example?
Read More →What is Serialization and deserialization in java given with example?
Read More →what are the different approach to make object Serializable? Other than Serialization.
Read More →What happens if the object to be serialized includes the references to other serializable objects?
Read More →What is the Difference between volatile and transient keyword in Java?
Read More →Serialization is NOT save the value of static class attributes. Why static variables are not serialized?
Read More →Can we overload main() method?
Read More →what are the the main keyword used in exceptation handling?
Read More →what are the the main keyword used in exceptation handling?
Read More →Why we need Aggregation?
Read More →Explain Java Exception Hierarchy followed by Throwable class?
Read More →What are important methods of Java Exception Class?
Read More →What is the relationship between a class and an object?
Read More →What is difference between Checked and Unchecked Exception in Java?
Read More →What is difference between throw and throws keyword in Java?
Read More →What are access modifiers?
Read More →How to write custom exception in Java?
Read More →What is OutOfMemoryError in Java?
Read More →What are different scenarios causing “Exception in thread main”?
Read More →What are access modifiers?
Read More →What is difference between final, finally and finalize in Java?
Read More →What are the various types of constructors?
Read More →What happens when exception is thrown by main method?
Read More →What is the difference between constructor and method?
Read More →Can we customize the Serialization process?
Read More →What changes are compatible and incompatible to the mechanism of java Serialization?
Read More →Can we have an empty catch block?
Read More →What is the difference between Error and Exception?
Read More →Can static block throw exception?
Read More →What is finally block?
Read More →Can we have a try block without catch or finally block?
Read More →Can we have a try block without catch or finally block?
Read More →what is the Difference between method Overloading and Overriding?.
Read More →Can we have multiple catch blocks following a single try block?
Read More →Is it possible to have finally block without catch block?
Read More →Can you declare the main method as final?.
Read More →When a finally block does not get executed?
Read More →Can we handle more than one exception in a single catch block?
Read More →How are the exceptions handled in java?
Read More →What is difference between abstract class and interface?
Read More →What is difference between ClassNotFoundException and NoClassDefFoundError?
Read More →What is throw keyword?
Read More →What is use of throws keyword?
Read More →What are the possible combination to write try, catch finally block?
Read More →What are the possible combination to write try, catch finally block?
Read More →How to create custom Exception?
Read More →What is JVM (Java Virtual Machine)?
Read More →What is JIT (Just- in-Time) Compilation?
Read More →What is Object Oriented Programming?
Read More →What is StackOverflowError?
Read More →what is Java Naming conventions?.
Read More →What’s the difference between “Abstract” classes and “Interfaces”?
Read More →What’s difference between Static and Non-Static fields of a class?
Read More →What are Class loaders?
Read More →What is Bootstrap, Extension and System Class loader?
Read More →What is Reflection API in Java?
Read More →What are the advantages of using exception handling?
Read More →What’s the difference between static and dynamic class loading?
Read More →What is String in Java? String is a data type?
Read More →Why String is an immutable Object?
Read More →What is use of synchronized keyword?
Read More →What are different ways to create String Object in java?
Read More →Can we use String in switch case?
Read More →what is the Difference Between String , StringBuilder and StringBuffer Classes in java?.
Read More →Can a thread call multiple synchronized methods on the object of which it hold the lock?
Read More →Can static methods be synchronized?
Read More →How many types of memory areas are allocated by JVM?
Read More →What are the various access specifiers for Java classes?
Read More →What is the difference between static binding and dynamic binding in java?
Read More →Can two threads call two different static synchronized methods of the same class?
Read More →What are synchronized methods and synchronized statements?
Read More →When you will synchronize a piece of your code?
Read More →Why synchronization is important?
Read More →What is Java String Pool?
Read More →Why String is popular HashMap key in Java?
Read More →What is Reflection in Java and where is used?
Read More →What are the disadvantage of using the reflection API?
Read More →How can you get the class object from a class name?
Read More →What are the basic Functionality of Reflection Api in Java?
Read More →How to access private field using Reflection in Java?
Read More →How to access private metod using Reflection in Java?
Read More →what string method in java?
Read More →what methods supported by String class in java?
Read More →What is Dynamic Class Loading using java Reflection Api ?
Read More →What do you understand by Executor Framework in Java, what is java executor framework
Read More →How to terminate a thread in Executor Framework in java?
Read More →Write a function to determine whether or not a string is a palindrome?.
Read More →What is the role of Executors.unconfigurableExecutorService in Executor Framework?
Read More →What are Difference Between String , StringBuilder and StringBuffer Classes with Example in Java ?
Read More →What is a wrapper class in java? Explain with examples.
Read More →What is the role of ExecutorService in Java?
Read More →What is String subSequence methodin java?.
Read More →What is difference between shutdownNow() and shutdown() in Executor Framework in java?
Read More →Write a method that will remove given character from the String in java?
Read More →How do you check if two Strings are equal in Java?
Read More →How to Split String in java?
Read More →What is Executors in java Executor Framework?
Read More →What is the role of FutureTask and Future in java?
Read More →What is the role of Executors.privilegedThreadFactory() in Executor Framework?
Read More →What are differences between JVM,JRE and JDK ?
Read More →Why Java does not support operator overloading ?
Read More →How can we make String upper case or lower case in java?.
Read More →What is the difference between creating string as new and literal in java?
Read More →Can we define two methods in a class with the same name?
Read More →What ie Thread Safety in java ?
Read More →What are the different policy in Executor Framework?
Read More →What is Anonymous Class in Java ?
Read More →How to get return value of a callable thread in java Executor Framework?
Read More →Why String is immutable or final in Java with example?.
Read More →What is difference between String and new String() in java?
Read More →What are the new features introduced in jdk 1.7?
Read More →Can we compare String using == operator? What is risk?
Read More →What is difference between Compare to and equals method in java?.
Read More →What is binary literals feature in jdk 1.7?
Read More →What is collection framework in Java? give its advantage?
Read More →How to create String buffer in java?.
Read More →What are the basic interfaces of Java Collections Framework?
Read More →What is the benefit of Generics in Collections Framework?
Read More →What are the Methods of Collection interface in Java?
Read More →What stringbuffer method in java used?.
Read More →What are difference between Iterator and ListIterator?
Read More →What StringBuilder method in java used?.
Read More →How we can use underscore in numeric lithrals in java 7?
Read More →What is the String inside switch feature of java 7?
Read More →How to use StringBulider method in java give example,and how to create it?.
Read More →what is the multi-catch feature of java 7?
Read More →What is the difference between Iterator and Enumeration ?
Read More →What is an Iterator ?
Read More →How do you traverse through a collection using its Iterator?
Read More →How to obtain Array from an ArrayList ?
Read More →What is the difference between Comparable and Comparator Interface?
Read More →What is difference between HashMap and HashSet?
Read More →What is difference between fail-fast and fail-safe?
Read More →How to make a collection read only?
Read More →what is the NIO.2 feature of java 7 new IO API?
Read More →What is Garbage Collection in Java?
Read More →what is the purpose of finalize() method in java?
Read More →Why we override equals() method in java?
Read More →What is legacy class in java ?
Read More →Why we use Map interface? What are main classes implementing Map interface?
Read More →Simple Example of ArrayList in Java .
Read More →Simple Example of LinkedList in Java .
Read More →Simple Example of ListIterator Interface in Java .
Read More →Simple Example of HashSet class in Java .
Read More →Simple Example of TreeSet class in Java .
Read More →Simple Example of Sorting the elements in Java .
Read More →Simple Example of PriorityQueue in Java .
Read More →Simple Example of HashMap class in Java .
Read More →Simple Example of LinkedHashMap class in Java .
Read More →Simple Example of TreeMap class in Java .
Read More →Which HTTP method is non-idempotent?
Read More →Which HTTP method is non-idempotent?
Read More →What is I/O in java?.
Read More →How do I write text to a file?
Read More →how to set file permissions in java?.
Read More →What is FileInputStream and FileOutputStream in java explain?.
Read More →How many ways can we read data from the keyboard?.
Read More →How to delete temporary file in java?
Read More →How to create temporary file in java?.
Read More →How to get list of all files from a folder in java?.
Read More →How to Filter the files by file extensions and show the file names in java?.
Read More →How to Filter the files by file extensions and show the file names in java?.
Read More →How to Filter the files by file extensions and show the file names in java?.
Read More →How to compress and uncompress the data of a file in java?.
Read More →How to create and store property file dynamically in java?.
Read More →How to store and read objects from a file in java?.
Read More →what is the diffrence b/w io and nio in java?.
Read More →How to read file content using byte array in java?.
Read More →How to get file URI reference in java?.
Read More →How to get file URI reference in java?.
Read More →How to get file last modified time in java?.
Read More →How to Write file handling program to copy characters from one file to another in java?.
Read More →How to count number of characters in a file in java
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