BC CREATIONOBJECTJAVA

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Vikas Rajput
@vikasrajputin 2 years, 8 months ago 217 views

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Five Different Ways to Create Objects in Java

a thread...

1. Using a new keyword.

It's the most popular one. We create an object by using a new operator followed by a constructor call.

Eg:

2. Using the newInstance() method of class "Class":

Eg:

3️. Using the newInstance() method in class "Constructor":

Eg:

Note:

Both the above ways (Shown in 2 and 3),
are known as reflective ways of creating objects.

Fun-fact:

Class's newInstance() method internally uses Constructor's newInstance() method.

4️. Using "Object" class clone() method

The clone() method creates a copy of an existing object.

The clone() method is part of the "Object" class which returns a clone object.

Eg:

When using the clone() method:

Always Remember,

1. The "Cloneable" interface is implemented.
2. The clone() method must be overridden with other classes.
3. Inside the clone() method, the class must call super.clone().

5️. Using Deserialization:

When we deserialize any object then JVM creates a new object internally.

For this, we need to implement the Serializable interface.

Eg:

Conclusion:

We've seen all five ways to create Objects in Java:

1. Using a new keyword.
2. Using Class.newInstance() method
3️. Using Constructor.newInstance() method
4️. Using Object.clone() method
5️. Using Deserialization

Thanks for reading!

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OOPs Concept in Java

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OOP Concepts are very common in Software Engineering.

All the OOP languages like Java, Python, C++, .Net, etc. have this concept.

In this thread, we'll try to understand it from Java's standpoint.

There are six different concepts in OOP:

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a thread...

In Java classes, we normally create the getter and setter methods to read and update class level fields respectively.

Let's find out why do we following this practice.

Consider a class "Account", having fields like accountName and accountBalance - to show the name and balance of the account.

As a common practice, both the variables are private and define the public getter and setter method to read and write their values.

Eg:

Using the above example, let's see different use-cases where having getter and setter methods can be game-changing.

1. Validation:

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a thread...

Streams are a way to perform operations on the whole collection of data.

Stream never modifies the source data, it processes it and gives us the result without modifying the original data.

Let's see few popular ways to create stream:

1. Collection. stream()
2. Stream.of(T... values)
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4. Stream.builder()

Eg:️

Consider stream as a pipeline, where we perform mainly two different operations on the source data:

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Here's what the stream pipeline looks like:

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Intermediate Operations(IO):

It returns another stream object, after this, we can either call another IO or TO.

Few methods in Stream API for Intermediate operations:
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- Features of Java
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I have to make a note before writing about this episode. I was the person (still am) who thinks that bringing back D. was a bad idea. I repeat it that for me the writing of S1 and S2 is like tossed into the bin with that plot evolution, but they had to invent something+
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2
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+he is justified the most to cry. With her resurrection now the attention shifts back to Miran’s storyline and I don’t know if I like this to be honest. This said, Dilsha is here and we have to deal with her.
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