47aa3aacee
* Better explanation I fixed the link from my last commit * Reordered changes, created "More Information"
61 lines
2.3 KiB
Markdown
61 lines
2.3 KiB
Markdown
---
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title: Inheritance Basics
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---
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# Inheritance Basics
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So great you have successfully created a Car class. But, wait, aren't Tesla cars supposed to be electric variants? I want an Electric car class, but it also should have the properties of the original `Car` class.
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Solution : **Inheritance**. Java provides a neat way to "inherit" parent properties :
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```java
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public class Car {
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private String name;
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private String manufacturerName;
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public Car(String name, String man) {
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this.name = name;
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this.manufacturerName = man;
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}
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// Getter method
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public String getName() {
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return name;
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}
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// Getter method
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public String getManufacturerName() {
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return manufacturerName;
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}
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}
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public class ElectricCar extends Car {
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public ElectricCar(String name, String man) {
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super(name, man);
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}
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public void charge() {
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System.out.println("Charging ...");
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}
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}
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ElectricCar modelS = new ElectricCar("Model S","Tesla");
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// prints Tesla
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System.out.println(modelS.getManufacturerName());
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// prints Charging ...
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modelS.charge();
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```
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 <a href='https://repl.it/CJZY/0' target='_blank' rel='nofollow'>Run Code</a>
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See here that the class `ElectricCar` inherits or `extends` the public methods from `Car` class, as well as has its own methods and properties. Cool way to pass on information!
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Inheritance is a way for *Object Oriented* languages to share properties from an existing class to a new class. The new class can use the properties of the old one, but the old one cannot use the new properties added into the new class.
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Also notice the usage of <a href='https://docs.oracle.com/javase/tutorial/java/IandI/super.html' target='_blank' rel='nofollow'>super</a> keyword here. Since our `Car` class had a constructor, so we have to initialize that constructor from the child class as well. We do that using the `super` keyword. Read more about <a>Inheritance here</a>.
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Inheritance is a way for *Object Oriented* languages to share properties from an existing class to a new class. The new class can use the properties of the old one, but the old one cannot use the new properties added into the new class.
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#### More Information
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- [Techopedia: Inheritance](https://www.techopedia.com/definition/3226/inheritance-java)
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