Java Reflection Learning notes three ways to instantiate 1--class class

Package Com.zq.demo;

Import java.util.Date;

public class Demo1 {public
     static void Main (string[] args) {
		   Demo1 d=new Demo1 ();
		   class<? Extends demo1> class1 = D.getclass ();
		   System.out.println (Class1.getname ()); 
		   System.out.println (Class1.getsimplename ());
		   Date Date=new date ();
           class<? Extends date> Class2 = Date.getclass ();
           System.out.println (Class2.getname ());
           System.out.println (Class2.getsimplename ());
     }

Output Result: Com.zq.demo.Demo1
Demo1
Java.util.Date

Date

Creates an object of class type by calling the GetClass () method from the object. This is one of the ways in which class objects are instantiated. But this approach is rarely used.

Second.

Package Com.zq.demo;

public class Demo2 {public
	static void Main (string[] args) {
		class cls = Java.util.Date.class;
		The loaded byte code is encapsulated into a class object

		String name = Cls.getname ();
		SYSTEM.OUT.PRINTLN (name);
		System.out.println (Cls.getsimplename ());

	}

Instantiate the class object by class name and class. There's more to this way.

Third.

Package Com.zq.demo;

public class Demo3 {public
  static void Main (string[] args) {
	 try {
		class<?> name = Class.forName ("ja Va.util.Date ");
		System.out.println (Name.getname ());
		System.out.println (Name.getsimplename ());
	} catch (ClassNotFoundException e) {
		//TODO auto-generated catch block
		e.printstacktrace ();
	}
}
}

Results of output:

Java.util.Date
Date

This approach is to instantiate a class type by Class.forName ("Class full Name"). This approach is more common in the framework, and is also used in JDBC technology to load the required drivers into the container.