ex_5_6_1.java

java思想编程与设计模块

/*
 *文件名:ex_5_6_1.java
 *说  明:访问控制演示
 */
package p1;

class Original
{
	int n_friendly = 1;
	private int n_private = 2;
	protected int n_protected = 3;
	public int n_public = 4;
	void Access( )
	{
		System.out.println("**** In same class, you can access ...");
		System.out.println("friendly member "+n_friendly);
		System.out.println("private member "+n_private);
		System.out.println("protected member "+n_protected);
		System.out.println("public member "+n_public);
	}
}

class Derived extends Original
{
	void Access( )
	{
		System.out.println("**** In subClass of same package, you can access member of this class ...");
		System.out.println("friendly member "+n_friendly);
		// System.out.println("private member "+n_private);
		System.out.println("protected member "+n_protected);
		System.out.println("public member "+n_public);
		Original o = new Original( );
		System.out.println("**** In subClass of same package, you can access member of superclass object ...");
		System.out.println("friendly member "+o.n_friendly);
		// System.out.println("private member "+o.n_private);
		System.out.println("protected member "+o.n_protected);
		System.out.println("public member "+o.n_public);
	}
}

class SamePackage
{
	void Access( )
	{
		Original o = new Original( );
		System.out.println("**** In the same package, you can access ...");
		System.out.println("friendly member "+o.n_friendly);
		// System.out.println("private member "+o.n_private);
		System.out.println("protected member "+o.n_protected);
		System.out.println("public member "+o.n_public);
	}
}

class AccessControl
{
	public static void main( String args[ ] )
	{
		Original o = new Original( );
		o.Access( );
		Derived d = new Derived( );
		d.Access( );
		SamePackage s = new SamePackage( );
		s.Access( );
	}
}