找不到main方法
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public class BaseClass { public int a = 5; } class SubClass extends BaseClass { public int a = 7; public void accessOwner() { System.out.println(a); } public void accessBase() { System.out.println(super.a); } public static void main(String[] args) { SubClass sc = new SubClass(); sc.accessOwner(); sc.accessBase(); } }这个程序显示找不到main方法,咋办。