Define a class

package t1;

public class T1 {
	
	private   int a = 10;/ / private
	          int b = 20;/ / the default
	protected int c = 30;// Protected
	public    int d = 40;/ / public
	
	public void name(a) { System.out.println(a); System.out.println(b); System.out.println(c); System.out.println(d); }}Copy the code

Test classes under the same package

package t1;

public class T2 {

	public static void main(String[] args) {
		T1 t1 = new T1();
//System.out.println(t1.a); Variables decorated with private are not available in other classes in the same packageSystem.out.println(t1.b); System.out.println(t1.c); System.out.println(t1.d); }}Copy the code

Test classes under different packages

package t2;

import t1.T1;

public class Test1 {
	public static void main(String[] args) {
		T1 t1 = new T1();
// System.out.println(t1.a); // The output class is not available
// System.out.println(t1.b); // By default, the same package can be accessed
// System.out.println(t1.c); // Protected variables are not accessible or inherited under different packages
		System.out.println(t1.d);// Use any variable that is modified by public}}Copy the code