汇总代码：

package people;

import java.util.Arrays;
import java.util.List;

import customLoader.FileSystemClassLoader;

/** 
 * @author: pyu
 * @Date: 2021/09/26
 */

public class Bootstrap {
    public static void main(String[] args) {
    	
    	//.class方法
    	System.out.println(".class方法");
    	Class<Person> clazz1 = Person.class; //拿类Person
    	Class<Bootstrap> clazz2 = Bootstrap.class; //拿本类Bootstrap
    	Class<FileSystemClassLoader> clazz3 = FileSystemClassLoader.class;
    	Class<TestInterf> clazz4 = TestInterf.class; //接口测试
    	System.out.println(clazz1.getCanonicalName()); //拿规范化名称
    	System.out.println(clazz2.getCanonicalName()); 
    	System.out.println(clazz3.getCanonicalName());
    	System.out.println(clazz4.getCanonicalName());
    	
    	//getClass()方法
    	System.out.println("getClass()方法");
    	List<Person> Persons = Arrays.asList(new Teacher(),new Student(),new Teacher(),new Person()); 
    	for(Person Person:Persons) {
    		if(Person.getClass().equals(Teacher.class)) { //若是Teacher则输出
    			Person.speak("I am a teacher");
    		}
    	}
    	
    	//forName()方法
    	System.out.println("forName()方法");
    	String className = "customLoader.Sample";
    	try {
    	Class<?> clazz = Class.forName(className);
    	System.out.println(clazz1.getCanonicalName()); //拿规范化名称
    	}catch(ClassNotFoundException e) {
    		e.printStackTrace();
    	}
    }
}

.class方法
people.Person
people.Bootstrap
customLoader.FileSystemClassLoader
people.TestInterf
getClass()方法
I am a teacher
I am a teacher
forName()方法
people.Person

目录

一、Class类

1. 通过.class属性获取类

 代码：

2. getClass()方法

代码： 

3. forName() 获取

代码： 

一、Class类

1. 通过.class属性获取类

 代码：

package people;

import customLoader.FileSystemClassLoader;

/** 
 * @author: pyu
 * @Date: 2021/09/26
 */

public class Bootstrap {
    public static void main(String[] args) {
    	Class<Person> clazz1 = Person.class; //拿类Person
    	Class<Bootstrap> clazz2 = Bootstrap.class; //拿本类Bootstrap
    	Class<FileSystemClassLoader> clazz3 = FileSystemClassLoader.class;
    	Class<TestInterf> clazz4 = TestInterf.class; //接口测试
    	System.out.println(clazz1.getCanonicalName()); //拿规范化名称
    	System.out.println(clazz2.getCanonicalName()); 
    	System.out.println(clazz3.getCanonicalName());
    	System.out.println(clazz4.getCanonicalName());
    }
}

 so.. 接口、本类也可以通过.class方法获取

2. getClass()方法

代码： 

package people;

import java.util.Arrays;
import java.util.List;
import customLoader.FileSystemClassLoader;

/** 
 * @author: pyu
 * @Date: 2021/09/26
 */

public class Bootstrap {
    public static void main(String[] args) {
    	//创建列表
    	List<Person> Persons = Arrays.asList(new Teacher(),new Student(),new Teacher(),new Person()); 
    	for(Person Person:Persons) {
    		if(Person.getClass().equals(Teacher.class)) { //若是Teacher则输出
    			Person.speak("I am a teacher");
    		}
    	}
    }
}

I am a teacher
I am a teacher

3. forName() 获取

代码： 

package people;

import customLoader.FileSystemClassLoader;

/** 
 * @author: pyu
 * @Date: 2021/09/26
 */

public class Bootstrap {
    public static void main(String[] args) {
    	String className = "customLoader.Sample";
    	try {
    	Class<?> clazz1 = Class.forName(className);
    	System.out.println(clazz1.getCanonicalName()); //拿规范化名称
    	}catch(ClassNotFoundException e) {
    		e.printStackTrace();
    	}
    }
}

customLoader.Sample