What Is The Piece Of Employment Of Course Of Pedagogy “Java.Lang.Class” Inwards Java?

java.lang.Class is ane of the close of import shape inward coffee only generally overlooked past times Java developers. It is really useful inward the feel that it provides several utility methods e.g. getClass(), forName() which is used to uncovering together with charge a class, you lot powerfulness bring used to charge Oracle or MySQL drivers. It every bit good provides methods similar Class.newInstance() which is the backbone of reflection together with let you lot to create an example of a shape without using new() operator.  The shape has no world constructor together with its example is created past times JVM when a shape is loaded. The object of shape Class is every bit good used to stand upward for classes, enum, interfaces together with notation inward a running Java application. The primitive types e.g. byte, short, char, int, float, double together with boolean are every bit good represented past times Class instances.


You tin larn the corresponding Class example past times using shape literals e.g. int.class, float.class or boolean.class. It is every bit good used to stand upward for an example of the array inward Java. Every array alongside the same type together with same dimension part the same example of shape Class.

Another role of java.lang.Class is spell implementing equals() method to banking firm check whether 2 objects are of the same type or not.

java.lang.Class shape inward Java

Every fourth dimension JVM creates an object, it every bit good creates a java.lang.Class object that describes the type of the object. All instances of the same shape part the same Class object together with you lot tin obtain the Class object past times calling the getClass() method of the object. By the way, this method is inherited from java.lang.Object class.

Suppose you lot create 2 instances of shape called Person e.g.

Person H5N1 = new Person(); Person B = new Person();  if(A.getClass() == B.getClass()){     System.out.println("A together with B are instances of same class"); }else{     System.out.println("A together with B are instances of dissimilar class"); }

In this case, it volition impress "A together with B are instances of the same class" because they are both example of shape Person.

We involve forName() together with newInstance() because many times it happens that nosotros don’t know the advert of the shape to instantiate spell writing code , nosotros may larn it from config files, database,network  or from whatsoever upstream Java or C++ application.

This is what nosotros called the reflective agency of creating an object which is ane of the close powerful characteristic of Java together with which makes agency for many frameworks e.g. Spring ,Struts which uses Java reflection.

Further Learning
Java Fundamentals Part 1 together with 2
Java Web Fundamentals
Head First Java sec Edition

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