How to inherit a class in java

In Java, properties and methods are inherited from the parent class through the extends keyword: subclasses can access parent class fields and call methods. Subclasses can use super() to call the parent class constructor. Subclasses can override parent class methods and extend functionality.

How to inherit classes in Java

Inheritance in Java is a basic concept of object-oriented programming. Allows one class (subclass) to inherit the properties and methods of another class (parent class). Through inheritance, subclasses can reuse the functionality of the parent class and extend or modify these functionality to create new functionality.

How to inherit a class

To inherit from a class, use the extends keyword, followed by the name of the parent class. For example, the following code shows how to inherit the Animal class:

<code class="java">public class Dog extends Animal {
  // Dog 类的代码
}</code>

What happens after inheritance

After inheritance, the child class will get the parent class of the following:

• Fields: Subclasses can access and use the fields of the parent class.
• Methods: Subclasses can call methods of parent classes.
• Constructor: Subclasses can use the super() keyword to call the constructor of the parent class.

Overriding and extending

Subclasses can override the methods of the parent class to provide different implementations. In addition, subclasses can add new fields and methods to extend the functionality of the parent class.

Example

The following example demonstrates the concepts of inheritance and overriding:

<code class="java">public class Animal {
  private String name;

  public String getName() {
    return name;
  }
}

public class Dog extends Animal {
  @Override
  public String getName() {
    return "Woof! " + super.getName();
  }
}</code>

In this example, the Dog class Inherits the Animal class and overrides the getName() method. When the getName() method is called, the Dog class will print "Woof!" and then call the parent class's method to get the name of the animal.

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