convertdemo.java

Java语言是目前最流行

//类与类之间的数据类型转换
class A
{
	String s="class:A";	
}
class B extends A
{
	String s="class : B";	
}
class TypeV
{
	public static void main(String[] aa)
	{
		B b1,b2 = new B();
		A a1,a2;
		a1 = (A)b2;
		a2 = b2;
		System.out.println(a1.s);
		System.out.println(a2.s);
		b1=(B)a1;
		System.out.println(b1.s);
	}	
}