classtest.java

孙鑫JAVA从入门到精通配套练习程序。所有程序都实际运行过

//演示Class类的用法
class ClassTest
{
	public static void main(String[] args)
	{
		/*
		//演示Class实例的获取
		Point pt = new Point();
		Class c1 = pt.getClass();
		System.out.println(c1.getName());
		
		try
		{
			Class c2 = Class.forName("Point");
			System.out.println(c2.getName());
		}
		catch(ClassNotFoundException ex)
		{
			ex.printStackTrace();
		}
		
		Class c3 = Point.class;
		System.out.println(c3.getName());
		
		int i = 3;
		Class c4 = int.class;
		System.out.println(c4.getName());
		
		Class c5 = Integer.TYPE;
		System.out.println(c5.getName());
		
		Class c6 = Integer.class;
		System.out.println(c6.getName());
		
		//演示.class文件的加载
		System.out.println("Before new Point");
		new Point();
		System.out.println("After new Point");
		try
		{
			Class.forName("Line");
		}
		catch(ClassNotFoundException ex)
		{
			ex.printStackTrace();
		}
		*/
		
		try
		{
		
			 Class c = Class.forName(args[0]);
			 Point p = (Point)c.newInstance();
			
		}
		catch(Exception ex)
		{
			ex.printStackTrace();
		}
		
		
	}
}

class Point
{
	int x, y;
	void output()
	{
		System.out.println("output Point");
	}
}

class Line
{
	static
	{
		System.out.println("Loading Line");
	}
}