命令提示符编译java的方法(必看篇)

package kun;public class HelloWorld{    public static void main(String[] args)  {    System.out.println("hello world");A a=new A();a.setValue(120);System.out.println(a.getValue());  }}class A{int value;public void setValue(int var){value=var;}public int getValue(){return this.value;}public A(){value=0;}}