Access level modifiers in Java are used to set the visibility of the class, interface and the visibility of fields, methods and constructors of the class. Access level modifiers determine whether other classes can use a particular field or invoke a particular method of a given class. Types of access…
When you create an instance of a class, constructor is called to initialize the instance variables. An alternative to using a constructor to initialize instance variable is to use initializer block in Java. Initializer block is always executed when an instance of the class is created. General form of Initializer…
ConcurrentHashMap in Java is a thread safe Map implementation which provides another alternative to be used in a multithreaded environment apart from HashTable or explicitly synchronizing HashMap. Where as HashMap in Java is not synchronized so not thread safe but provides better performance. In this post we’ll see the difference…
ArrayList is part of Java from version 1.2 where as CopyOnWriteArrayList was added in Java 5 as a thread-safe variant of ArrayList. In this post we’ll see the differences between ArrayList and CopyOnArrayList in Java. CopyOnWriteArrayList Vs ArrayList in Java 1- Thread Safety: CopyOnWriteArrayList is thread safe. Thread safety in…
Both CountDownLatch and CyclicBarrier are synchronization aids in Java concurrency that facilitate communication among threads. Both of these synchronization aids create a latch or a barrier to make threads wait until a condition is satisfied and then only the threads can make further progress. In this post we’ll see the…
The traditional way of acquiring a mutual exclusion lock in Java is to use synchronized keyword but Java 5 added new lock implementations like ReentrantLock and ReentrantReadWriteLock which provide extended locking operations capabilities. In this post we’ll see the difference between synchronized and ReentrantLock in Java. ReentrantLock Vs synchronized in…
Once you create a class in Java that defines a new data type which can be used for creating object of that data type (class). Thus object in Java is an instance of the class, which gets its state and behavior from the class. Fields defined within a class are…
A class is the foundation for object oriented programming in Java language. Any logic that has to be implemented in Java must be encapsulated with in the class. Once a class is created in Java that defines a new data type which can be used for creating object of that…
Constructor overloading in Java is the process similar to method overloading which means with in a class you can have more than one constructor where the constructors differ in the number of parameters. What is the use of having overloaded constructor Constructor overloading in Java brings the flexibility of initializing…
Constructor chaining in Java is the process of calling one constructor from another constructor with in the same class or calling the parent class constructor from the child class. So constructor chaining in Java can be done in two ways- When calling one constructor from another with in the same…