请各位Java高手帮忙: 已知一个类如下所示class S{ double r;}编写S的一个子类,该子类中包含一个计算圆面积的方法area()和一个使用supper()初始化S类成员的构造方法 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 class S { double r; public S(double rr){ this.r = rr; }}public class ss extends S { public ss(double rrr){ //构造函数 super(rrr); } public double getArea(){ //获取面积 return 3.14*r; } public static void main(String[] args){ ss sss = new ss(10); System.out.println("面积为"+sss.getArea()); }} /** * project_name: Test * package_name: csdn_Test_20071126 * package_declaration: package csdn_Test_20071126; * filename: SuperClassTest.java * author: yuhaiming * date: 2007-12-5 */package csdn_Test_20071126;class fatherClass{ double s; public fatherClass(double value){ this.s=value; }}public class SuperClassTest extends fatherClass{ public SuperClassTest(){ super(20); } /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub SuperClassTest classTest = new SuperClassTest(); System.out.println(classTest.s); }} /** * project_name: Test * package_name: csdn_Test_20071126 * package_declaration: package csdn_Test_20071126; * filename: SuperClassTest.java * author: yuhaiming * date: 2007-12-5 */package csdn_Test_20071126;class fatherClass{ double s; public fatherClass(double value){ this.s=value; }}public class SuperClassTest extends fatherClass{ public SuperClassTest(){ super(20); } public static double areaCom(double r){ return 3.14*r*r; } /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub SuperClassTest classTest = new SuperClassTest(); System.out.println("面积:"+areaCom(classTest.s)); }} public class ss extends S { public ss(double rrr){ super(rrr); } public double getArea(){ return 3.14*r*r; } public static void main(String[] args){ ss sss = new ss(10); System.out.println("面积为"+sss.getArea()); }} 如何对窗口中的Component进行排版 关于jdk的版本 JAVA核心技术 急求 新手问题,JSP中比如文本框的Null值,selvert中能取到吗,能进行判断吗 正则表达式的问题,谢谢大家帮忙了 在solaris系统中JDK环境变量的配置 运行的时候 说这个方法报空指针啊 求大神解答!!! 请问一个JDBC的问题~~~~~ 在winme中怎样配置j2sdk的环境? 请问我将如何访问局域网上的文件?急急!!谢谢!!! JAVA与C++语言比较 菜鸟请进---java初学者项目实践
double r;
public S(double rr){
this.r = rr;
}
}
public class ss extends S { public ss(double rrr){ //构造函数
super(rrr);
}
public double getArea(){ //获取面积
return 3.14*r;
}
public static void main(String[] args){
ss sss = new ss(10);
System.out.println("面积为"+sss.getArea());
}
}
* project_name: Test
* package_name: csdn_Test_20071126
* package_declaration: package csdn_Test_20071126;
* filename: SuperClassTest.java
* author: yuhaiming
* date: 2007-12-5
*/
package csdn_Test_20071126;
class fatherClass{
double s;
public fatherClass(double value){
this.s=value;
}
}
public class SuperClassTest extends fatherClass{
public SuperClassTest(){
super(20);
}
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
SuperClassTest classTest = new SuperClassTest();
System.out.println(classTest.s);
}}
/**
* project_name: Test
* package_name: csdn_Test_20071126
* package_declaration: package csdn_Test_20071126;
* filename: SuperClassTest.java
* author: yuhaiming
* date: 2007-12-5
*/
package csdn_Test_20071126;
class fatherClass{
double s;
public fatherClass(double value){
this.s=value;
}
}
public class SuperClassTest extends fatherClass{
public SuperClassTest(){
super(20);
}
public static double areaCom(double r){
return 3.14*r*r;
}
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
SuperClassTest classTest = new SuperClassTest();
System.out.println("面积:"+areaCom(classTest.s));
}}
public ss(double rrr){
super(rrr);
}
public double getArea(){
return 3.14*r*r;
}
public static void main(String[] args){
ss sss = new ss(10);
System.out.println("面积为"+sss.getArea());
}
}