website/content/ta/spring2018/cpsc220/apr3.md
2020-01-15 21:51:49 -05:00

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# Lecture for April 3rd
## Inheritance
The *base class*, *super class*, or *parent class* is the initial class that we are working with. Let's say that you want to *extend* the class, or add additional functionality. The class that inherits from the parent class is called the *child class*, *subclass* or *derived class*.
## Child Class Syntax
```java
public class Truck extends Car {
// Truck Appropriate Fields
// Necessary methods for truck
}
```
This code adds all the methods from Car into the Truck class. You can then add methods that is specific to a Truck into the Truck class.
A child class has all parent fields and access to all parent methods!
## Visibility Modifiers
Recall the words `public` and `private`
The `public` modifier makes the field/method accessible by any class
The `private` modifier makes the field/method only accessible within the method itself
The protected modifier makes the field/method accessible within the same class or any subclasses.
## Overriding a Method
You can override a parent class method by declaring a method in the child class with the same...
- name
- number of paramters
- parameter types
but this method would have different behavior!