Java语言学习十（封装/继承）

叁歲伎倆 2023-07-19 12:19 19阅读 0赞

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import java.util.*;
    
    class A
    { 
    	public A()
    	{ 
    		System.out.println("创建对象A");
    	}
    }
    
    class B extends A
    { 
    	public B()
    	{ 
    		System.out.println("创建对象B");
    	}
    }
    
    class C extends B
    { 
    	public C()
    	{ 
    		System.out.println("创建对象C");
    	}
    }
    
    public class Test 
    { 
    	public static void main(String[] args)
    	{ 
    		C c = new C();
    	}
    }

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## 访问方法与属性 ##

访问属性时访问父类对象的属性  
访问方法时访问子类对象的方法

import java.util.*;
    
    class A
    { 
    	String name = "A";
    	public String getName(){ 
    		System.out.println("调用A的方法");
    		return name;
    	}
    
    }
    
    class B extends A
    { 
    	String name = "B";
    	public String getName(){ 
    		System.out.println("调用B的方法");
    		return name;
    	}
    }
    
    class C extends B
    { 
    	String name = "C";
    	public String getName(){ 
    		System.out.println("调用C的方法");
    		return name;
    	}
    }
    
    public class Test 
    { 
    	public static void main(String[] args)
    	{ 
    		A a = new A();
    		A b = new B();
    		A c = new C();
    		System.out.println(a.name);
    		a.getName();
    		System.out.println(b.name);
    		b.getName();
    		System.out.println(c.name);
    		c.getName();
    	}
    }

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## 访问修饰符 ##

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