53 lines
1.7 KiB
Markdown
53 lines
1.7 KiB
Markdown
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---
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title: Inheritance Basics
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localeTitle: 继承基础
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---
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# 继承基础
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你成功创建了一个Car类，真是太棒了。但是，等等，特斯拉汽车应该是电动车？我想要一个电动车类，但它也应该具有原始`Car`类的属性。
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解决方案： **继承** 。 Java提供了一种“继承”父属性的简洁方法：
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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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 [运行代码](https://repl.it/CJZY/0)
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在这里看，类`ElectricCar`从`Car`类继承或`extends`公共方法，并且有自己的方法和属性。传递信息的酷方式！
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另请注意这里使用[super](https://docs.oracle.com/javase/tutorial/java/IandI/super.html)关键字。由于我们的`Car`类有一个构造函数，所以我们也必须从子类初始化该构造函数。我们使用`super`关键字来做到这一点。阅读更多关于继承的信息 。
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