由于是英語學(xué)渣。大家湊合看拼英。

//以下是父類

package com.imoocc;

public abstract class tuxing {
?public double chang=5;
?public double kuang=4;
?public double banjing=10;
public abstract void zhouchang();
public abstract void mianji();
}

//以下是子類

package com.imoocc;

public abstract class juxing extends tuxing {

?@Override
?public void zhouchang() {
??// TODO Auto-generated method stub
??
??double zhouchang=(chang+kuang)*2;
?System.out.println("矩形的周長(zhǎng)是:"+zhouchang);
?}

?@Override
?public void mianji() {
??// TODO Auto-generated method stub
???? double mianji=chang*kuang;
??? System.out.println("矩形的面積是:"+mianji);
?}

}

//以下是子類

package com.imoocc;

public abstract class yuanxing extends tuxing {

?@Override
?public void zhouchang() {
??// TODO Auto-generated method stub
?? double zhouchang=2*3.14*banjing;
?System.out.println("圓形的周長(zhǎng)是:"+zhouchang);
?}

?@Override
?public void mianji() {
??// TODO Auto-generated method stub
?? double mianji=3.14*(banjing*banjing);
?System.out.println("圓形的面積是:"+mianji);
?}

}

//以下是測(cè)試類

package com.imoocc;

public class ceshi {

?public static void main(String[] args) {
??// TODO Auto-generated method stub
???? tuxing a=new juxiang ();
?}

}

寫到測(cè)試類的時(shí)候這句指定對(duì)象的時(shí)候eclipse報(bào)錯(cuò)了，報(bào)的是juxiang cannot be resolved to a type

想問一下哪里是有錯(cuò)誤的，找了好久沒找出來，謝謝