There are five ways to create objects in Java, which are:
1. Use the new keyword
This is the most common and simplest creation object way. In this way, we can call any constructor (parameterless and parameterized).
Employee emp1 = new Employee();
2. Use the newInstance method of the Class class
This newInstance method calls the parameterless constructor to create an object.
We can create objects by calling the newInstance method in the following way:
Employee emp2 = Employee.class.newInstance();
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3. Use the Constructor class The newInstance method
is very similar to the newInstance method of the Class class. There is also a newInstance method in the java.lang.reflect.Constructor class that can create objects. We can call parameterized and private constructors through this newInstance method.
Constructorconstructor = Employee.class.getConstructor(); Employee emp3 = constructor.newInstance();
4. Use the clone method
Whenever we call the clone method of an object, the jvm will create a new object and copy all the contents of the previous object into it. Creating an object using the clone method does not call any constructor.
To use the clone method, we need to first implement the Cloneable interface and implement the clone method defined by it.
Employee emp4 = (Employee) emp3.clone();
5. Use deserialization
When we serialize and deserialize an object, jvm will create a separate object for us. During deserialization, the jvm creates the object and does not call any constructor. In order to deserialize an object, we need to make our class implement the Serializable interface.
ObjectInputStream in = new ObjectInputStream(new FileInputStream("data.obj")); Employee emp5 = (Employee) in.readObject();
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