验证可以存在 (但是没有意义 )abstract class clsTest{ public static int GetInt() { return 1; } //public abstract void eat(); }class clsTest2 extends clsTest{ public void sleep(){ System.out.println("Dog sleep."); } public void eat(){ System.out.println("Dog eat."); }} int i ; clsTest k=null; k=new clsTest2(); k.GetInt(); k.sleep();------错误Exception in thread "main" java.lang.Error: Unresolved compilation problem: The method sleep() is undefined for the type clsTest
最简单的
public abstract class Main {}
)abstract class clsTest{
public static int GetInt()
{ return 1; }
//public abstract void eat();
}class clsTest2 extends clsTest{
public void sleep(){
System.out.println("Dog sleep.");
}
public void eat(){
System.out.println("Dog eat.");
}}
int i ;
clsTest k=null;
k=new clsTest2();
k.GetInt();
k.sleep();------错误Exception in thread "main" java.lang.Error: Unresolved compilation problem:
The method sleep() is undefined for the type clsTest