一个类只可以继承一个类，
一个接口却可以继承多个接口。
父类的方法，子类继承后如果重写。则创建子类对象后使用该方法调用的是子类中的该方法。 否则，即没有修改父类里的方法，调用的就仍是父类方法。
package 复习;
class Base{
void f(){System.out.println("调用的是父类里的方法!");}
}
public class Test extends Base {
public void f(){
//super.f();
System.out.println("调用的是子类里的方法！");
}
public static void main(String[] args) {
Base b1=new Test();
Test t1=new Test();
b1.f();
t1.f();
}
}
调用的是子类里的方法！
调用的是子类里的方法！
package 复习;
class Base{
void f(){System.out.println("调用的是父类里的方法!");}
}
public class Test extends Base {
public void f(){
//super.f();
System.out.println("调用的是子类里的方法！");
}
public static void main(String[] args) {
Base b1=new Base();
Test t1=new Test();
b1.f();
t1.f();
}
}
调用的是父类里的方法!
调用的是子类里的方法！
一个接口可以继承多个接口，最终某类再执行该接口（集成了多个接口的接口）时，必须实例化所有抽象函数。 当然，这个类同时也可以继承一个父类，倘若该父类中的 方法 shortage（）在接口AsianMan中已有，这个子类依然要实例化shortage（）方法，且该子类对象在调用时使用的是接口中的shortage（）！！！
package interfaces;
interface Animal{
void eat();
}
interface Human{
void drink();
}
interface Man{
void run();
}
interface AsianMan extends Animal,Human,Man{
void shortage();
}
class HeNanMan{
void shortage(){
System.out.println("But he was slightly inferior, especially in matters of taste and style .");
}
}
class ME extends HeNanMan implements AsianMan{
public void eat(){System.out.print("This type can eat, ");}
public void drink(){System.out.print("can drink,");}
public void run(){System.out.print(" can run.");}
public void shortage(){System.out.println("But he has few ambition !!!");}
}
public class TryInterface {
public static void main(String[] args) {
ME fc=new ME();
fc.eat();
fc.drink();
fc.run();
fc.shortage();
//fc.shortage();
}
}
output： This type can eat, can drink, can run.But he has few ambition !!!
假使没有冲突，那都可以调用。
package interfaces;
void eat();
}
interface Human{
void drink();
}
interface Man{
void run();
}
interface AsianMan extends Animal,Human,Man{
void shortage();
}
class HeNanMan{
void shortage2(){
System.out.println(" and he was slightly inferior, especially in matters of taste and style .");
}
}
class ME extends HeNanMan implements AsianMan{
public void eat(){System.out.print("This type can eat, ");}
public void drink(){System.out.print("can drink,");}
public void run(){System.out.print(" can run.");}
public void shortage(){System.out.print("But he has few ambition !!!");}
}
public class TryInterface {
public static void main(String[] args) {
ME fc=new ME();
fc.eat();
fc.drink();
fc.run();
fc.shortage();
fc.shortage2();
}
}
output： This type can eat, can drink, can run.But he has few ambition !!! and he was slightly inferior, especially in matters of taste and style .
接口可以选择性继承，只执行一部分抽象方法
package interfaces;
interface Animal{
void eat();
}
interface Human{
void drink();
}
interface Man{
void run();
}
interface AsianMan extends Animal,Human{
void shortage();
}
class HeNanMan{
void run(){System.out.print("can run more faster than other province. ");}
void shortage2(){
System.out.println("and he was slightly inferior, especially in matters of taste and style .");
}
}
class ME extends HeNanMan implements AsianMan{
public void eat(){System.out.print("This type can eat, ");}
public void drink(){System.out.print("can drink,");}
//public void run(){System.out.print(" can run.");}
public void shortage(){System.out.print("But he has few ambition !!!");}
}
public class TryInterface {
public static void main(String[] args) {
ME fc=new ME();
fc.eat();
fc.drink();
fc.run();
fc.shortage();
fc.shortage2();
}
}
output： This type can eat, can drink,can run more faster than other province. But he has few ambition !!!and he was slightly inferior, especially in matters of taste and style .