As per java, a class is nothing but blueprint of an objects, We create an object from a class.
We have different ways to create object for class in Java.
1) Using new Keyword :
Creating Object with new keyword is the common way in java. By using this way we can call any constructor we want to call (no argument or parameterized constructors).
publicclass ObjectWithNew
{
String name = "New Key Word";
publicstaticvoidmain(String[] args)
{
// Here we are creating Object of
// ObjectWithNew using new keyword
ObjectWithNew obj = new ObjectWithNew();
System.out.println(obj.name);
}
}
2) Using New Instance : Suppose if we know the name of the class & it has a public default constructor we can create an object by Class.forName. Class.forName loads the Class in Java, it doesn’t create any Object. To Create an Object of the Class we have to use the new Instance Method of the Class.
publicclassObjectWithNewInstance
{
String name = "Object with New Instance";
publicstaticvoidmain(String[] args)
{
try
{
Class cls = Class.forName("ObjectWithNewInstance");
ObjectWithNewInstanceobj =
(ObjectWithNewInstance) cls.newInstance();
System.out.println(obj.name);
}
catch(ClassNotFoundException e)
{
e.printStackTrace();
}
catch(InstantiationException e)
{
e.printStackTrace();
}
catch(IllegalAccessException e)
{
e.printStackTrace();
}
}
}
3) Using clone() method:
On calling clone() for any object, the JVM creates a new object and copies all content of the previous object into it. Creating an object by the clone method does not invoke any constructor.
To use clone() method for an object we need to implement Cloneable and define the clone() method in it.