Java 面向对象：访问权private、public、常量、protected

package com.neusoft.pg;

import java.awt.Button;
import java.awt.Frame;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import com.neusoft.guess.Person;

/**
 * 包：package 作用： 1.解决命名冲突的问题 2.进行分类
 * 
 * 使用import关键字引入其它包中的类 import com.neusoft.guess.Person; 位于同一包中的类可以直接访问
 * 
 * @author ttc
 *
 */
public class A {
	public static void main(String[] args) {
		Person person = new Person();
		String ss = "asdfadsf";
		Button button = new Button("abc");
	}
}

package AccessContral_mypack1;

public class A {
	private int var1;
	public int var2;
	int var3;
	protected int var4;
	
	public void method() {
		var1 = 1;
		var2 = 1;
		var3 = 1;
		var4 = 1;
	}
}

package AccessContral_mypack1;

public class B {
	public static void main(String[] args) {
		A a = new A();
		a.var2 = 1;
		a.var3 = 1;
		a.var4 = 1;
//		a.var1 = 1;
	}
}

package AccessContral_mypack2;

import AccessContral_mypack1.A;

public class C extends A{
	public static void main(String[] args) {
		C c = new C();
		c.var2 = 1;
		c.var4 = 1;
		

	}
}

package AccessContral_mypack2;

import AccessContral_mypack1.A;

public class D {
	public static void main(String[] args) {
		A a = new A();
		a.var2 = 1;
	}
}