µ±Ç°Î»ÖãºÊ×Ò³ > ÆÚÄ©¸´Ï°Ìâ
}
public double findArea() {
return 2*(3/4)*bian*bian +3*bian*length; } }
11£®¶¨ÒåÒ»¸öÀ࣬ÃèÊöÒ»¸ö¼ÒÍ¥£¬ÆäÖаüÀ¨Ë½ÓеÄÇ®Êý£¨ÊôÐÔ£©¡¢Êܱ£»¤µÄ׿´«ÃØ·½£¨·½·¨£¬
ÔÚÆäÖÐдÊä³öÓï¾äÄ£Äâ¼´¿É£©¡¢Ö»ÔÚ¼Ò×åÖÐÄܹ»Ê¹ÓõÄÔËÊ乤¾ß£¨·½·¨£¬ÔÚÆäÖÐдÊä³öÓï¾ä½øÐÐÄ£Ä⣩£¬¹«¹²µÄÃÅÅÆºÅÂ루ÊôÐÔ£©¡£½«Õâ¸ö¼ÒÍ¥·ÅÖÃÔÚÒ»¸ö°üÖУ¨Ò»¸ö´óÔº£©£¬±àдһ¸ö¸Ã¼ÒÍ¥µÄ×ÓÀ࣬·ÅÖÃÔÚÁíÒ»¸ö°üÖС£²âÊÔÆäÖм¸ÖÖ±»¿É¼ûÐÔÐÞÊηûÐÞÊιýµÄÊôÐԺͷ½·¨¡£ ³ÌÐòÒ»£º
package yard;
public class Family{ private double money; void useCar(){ System.out.println(\ } protected void peiFang(){ System.out.println(\ } public int familyNum; } ³ÌÐò¶þ£º
package dalian;
import yard.Family; public class TestVisible{ public static void main(String[] args){ Family f=new Family();
System.out.println(\ÃÅÅÆºÅÂëÊÇ£º\ //System.out.println(\Ç®Êý\ //f.useCar(); //f.peiFang();
SunFamily sf=new SunFamily(); //sf.peiFang(); sf.usePeiFang(); } }
class SunFamily extends Family{ public void usePeiFang(){ this.peiFang(); }
25
public void usePlane(){ System.out.println(\ } }
12£®¶¨ÒåÒ»¸ö½Ó¿ÚCanFly£¬ÃèÊö»á·ÉµÄ·½·¨public void fly();
·Ö±ð¶¨ÒåÀà·É»úºÍÄñ£¬ÊµÏÖCanFly½Ó¿Ú¡£
¶¨ÒåÒ»¸ö²âÊÔÀ࣬²âÊÔ·É»úºÍÄñ£¬ÔÚmain·½·¨Öд´½¨·É»ú¶ÔÏóºÍÄñ¶ÔÏó£¬ÔÙ¶¨ÒåÒ»¸ömakeFly()·½·¨£¬ÆäÖÐÈûá·ÉµÄÊÂÎï·É¡£²¢ÔÚmain·½·¨Öе÷Óø÷½·¨£¬È÷ɻúºÍÄñÆð·É¡£ class InterfaceSample
{
public static void main(String arg[]) { Plane p1=new Plane(); Bird b1=new Bird(); Dog d1=new Dog(); makeFly(p1); makeFly(b1);
if (d1 instanceof CanFly)//×÷ÓÃËÄ£ºÓÃinstanceofÅжÏÊÇ·ñʵÏÖÁ˽ӿڣ¬¼´ÊÇ·ñÄÜ·É { System.out.println(\ makeFly((CanFly)d1); }
CanFly f1=new Plane(); CanFly f2=new Bird(); makeFly(f1); makeFly(f2); }
static void makeFly(CanFly f) {f.fly();} }
interface CanFly { void fly();}
class Plane implements CanFly { public void fly()
{ System.out.println(\ } }
class Bird implements CanFly { public void fly()
{System.out.println(\ }
class Dog{ void run(){System.out.println(\
26
}
13. ÀûÓýӿڼ̳ÐÍê³É¶ÔÉúÎï¡¢¶¯Îï¡¢ÈËÈý¸ö½Ó¿ÚµÄ¶¨Ò壬ÆäÖÐÉúÎï½Ó¿Ú¶¨ÒåºôÎü³éÏó·½·¨£¬¶¯Îï½Ó¿Ú¶¨ÒåÁ˳Է¹ºÍ˯¾õÁ½¸ö³éÏó·½·¨£¬È˽ӿڶ¨ÒåÁË˼άºÍѧϰÁ½¸ö³éÏó·½·¨£»¶¨Ò»¸öÆÕͨÈË ÀàʵÏÖÉÏÊöÈý¸ö½Ó¿Ú¶¨ÒåµÄ³éÏó·½·¨¡£ interface Biology {
void breath(); }
interface Animal extends Biology {
void ate();
void sleep(); }
interface Man extends Animal {
void think(); void study(); }
class NormalMan implements Man,Animal,Biology {
private String name;
NormalMan(String name) { this.name=name;} public String getName() { return name;} public void breath()
{ System.out.println(name+\ public void ate()
{ System.out.println(name+\ public void sleep()
{ System.out.println(name+\ public void think()
{ System.out.println(name+\ public void study()
{ System.out.println(name+\ }
public class InterfaceExtend {
public static void main(String[] args) {
NormalMan zhangsan=new NormalMan(\ zhangsan.breath(); zhangsan.ate();
27
zhangsan.sleep(); zhangsan.think(); zhangsan.study(); } }
14 ½Ó¿ÚVolumeÈçÏ£¬ÊÔ±àÖÆÀàTriVolumeʵÏָýӿڣ¬²¢¼ÆËãÈýÀâÖùµÄÌå»ý(µ×ÃæÎªµÈ±ßÈý½ÇÐÎ)¡£ ½Ó¿ÚΪ£º
Public interface Volume {
public double findVolume(double bian, double length); }
ÀàΪ£º class Trival { double bian; Trival() { bian=1.0; } Trival(double b) { bian=b; } double findArea() {
return (3/4)*bian*bian;
} }
´ð°¸£º
class TriVolume extends Trival implements Volume {
double bian,length;
TriVolume(double b, double l) {
super(b); length=l; }
public double findArea() {
28
¹²·ÖÏí92ƪÏà¹ØÎĵµ