求java的实现继承的一个列子?
A 输出1
B 输出2
要能用的
------解决方案--------------------class Parent{
public Parent(){
System.out.println( "1 ");
}
}
public class Child extends Parent{
public Child(){
System.out.println( "2 ");
}
public static void main(String[] args) {
new Child();
}
}
------解决方案--------------------class Parent{
public Parent(){
public void test(){
System.out.println( "1 ");
}
}
}
public class Child extends Parent{
public Child(){
//覆盖上层方法
public void test(){
System.out.println( "2 ");
}
}
}
test.java:
public static void main(String[] args) {
Parent a = new Parent();
Child b = new Child();
a.test();
b.test();
}
------解决方案--------------------//父类
class Parent{
public Parent(){
private void test(){
System.out.println( "1 ");
}
}
}
//子类继承父类
class Child extends Parent{
public Child(){
//覆盖上层方法
private void test(){
System.out.println( "2 ");
}
}
}
public class test{
public static void main(String[] args) {
Parent a = new Parent();
Child b = new Child();
a.test();
b.test();
}
}
------解决方案--------------------public class Test {
public static void main(String[] args) {
Parent p1 = new Parent();
Parent p2 = new Child();
p1.test();
p2.test();
}
}
class Parent {
public void test() {
System.out.println( "My name is Parent. ");
}
}
class Child extends Parent {
public void test() {
System.out.println( "My name is Child. ");
}
}
------解决方案--------------------你照着”蟑螂“的代码自己重新打一遍,不要ctrl+c,他上面的代码带空格~
------解决方案--------------------学习
------解决方案--------------------class Parent
{
Parent(){}
void show(){
System.out.println( "1 ");
}
}
class Child extends Parent
{Child(){}
void disp(){
System.out.println( "2 ");}
}
class ParentTest{
public static void main(String[] args)
{
Parent a = new Parent();
Child b = new Child();
a.show();
b.disp();
}
}
------解决方案--------------------还是用IDE方便~
------解决方案--------------------用eclipse,再把他们的代码敲进去,复制总是会出现一些意外的!