瀹氫箟鎶借薄綾繪按鏋滐紙Fruit錛?br /> public abstract class Fruit {
……
}
濡傛灉鎴戜滑璇曞浘鐢ㄤ互涓嬭鍙ユ潵鑾峰緱涓涓疄渚嬶紝灝嗘棤娉曠紪璇戞垚鍔熴?br /> Fruit fruit = new Fruit();
鑰屾垜浠粛鐒跺彲浠ユ瀯閫犳按鏋滅被鐨勫瓙綾伙紝濡傦細
瀛愮被“鑻規灉錛圓pple錛?#8221;
public class Apple extends Fruit {
……
}
瀛愮被“姍樺瓙錛圤range錛?#8221;
public class Orange extends Fruit {
……
}
榪欐牱灝辮揪鍒版垜浠殑鐩殑浜嗐?br /> 鎶借薄綾婚櫎浜嗚兘璞℃櫘閫氱被涓鏍峰彲浠ユ嫢鏈変竴鑸殑灞炴у拰鏂規硶錛屼篃鍙互鎷ユ湁鎶借薄鏂規硶錛坅bstract method錛夈備緥濡傦細
鎶借薄綾?#8220;褰㈢姸錛圫hape錛?#8221;鎷ユ湁鎶借薄鏂規硶draw()銆?br /> public abstract class Shape {
……
public abstract void draw();
……
}
鎶借薄鏂規硶涓庢娊璞＄殑琛屼負鐩稿搴旓紝閫氬父鏄繖涓涓哄鐖跺璞℃病鏈夋剰涔夛紝鑰屽瓙瀵硅薄鏈夊叿浣撳姩浣溿備緥濡傛柟娉昫raw()瀵逛簬綾籗hape娌℃湁鎰忎箟錛岃岀被Shape鐨勫瓙綾葷煩褰紙Rectangle錛夌殑鏂規硶draw()鍙互鏈夊疄闄呯殑鍔ㄤ綔錛堟牴鎹煩褰㈢殑鍥涗釜欏剁偣鐢誨嚭鐭╁艦鐨勫洓涓竟錛夛紝瀛愮被鍦嗭紙Circle錛夌殑鏂規硶draw()涔熷彲浠ユ湁瀹為檯鐨勫姩浣滐紙鏍規嵁鍦嗗績鍜屽崐寰勭敾鍑哄渾鍛級銆?br /> 鎶借薄綾誨彲浠ユ湁鎶借薄鏂規硶涔熷彲浠ユ病鏈夋娊璞℃柟娉曪紱浣嗘槸濡傛灉涓涓被鏈夋娊璞℃柟娉曪紝閭ｈ繖涓被鍙兘瀹氫箟涓烘娊璞＄被銆?br /> 濡傛灉鎸夌収浠ヤ笅浠ｇ爜綾?#8220;褰㈢姸錛圫hape錛?#8221;浠嶇劧鎷ユ湁鎶借薄鏂規硶draw()錛屼絾娌℃湁瀹氫箟涓烘娊璞＄被錛屽皢浼氱紪璇戝け璐ャ?br /> public class Shape {
……
public abstract void draw();
……
}
鎶借薄鏂規硶榪樻湁涓涓壒鐐規槸錛屽畠寮鴻揩瀛愮被瑕佷箞浠嶇劧淇濇寔鎶借薄鎬э紙鍗充笉鍏蜂綋瀹炵幇璇ユ柟娉曞茍浠嶇劧瀹氫箟涓烘娊璞＄被錛夛紝瑕佷箞鍏蜂綋琛ㄧ幇鍑鴻繖涓柟娉曠殑琛屼負錛堝疄鐜板叿浣撶殑鍔ㄤ綔鎴栬呴氳繃鎶涘嚭UnsupportedOperationException寮傚父鏉ヨ〃鏄庝笉鏀寔璇ヨ涓猴級銆傝繖鏍蜂篃鍙互寮哄寲澶氭佹с?br />
2錛氭帴鍙ｏ紙interface錛?br /> java璇█浣跨敤鍏抽敭瀛梚nterface瀹氫箟涓涓帴鍙ｃ傛帴鍙ｄ篃鏄娊璞″璞★紝瀹冪敋鑷蟲瘮鎶借薄綾繪洿鎶借薄銆傛帴鍙ｄ腑鐨勬柟娉曢兘鏄娊璞℃柟娉曘?br /> 涓涓帴鍙ｅ彲浠ョ戶鎵垮叾浠栨帴鍙ｏ紱涓涓被閫氳繃鍏抽敭瀛梚mplements澹版槑瑕佸疄鐜頒竴涓帴鍙ｏ紝騫跺叿浣撳疄鐜版帴鍙ｇ殑鏂規硶銆?br /> 渚嬪錛氭湁涓涓帴鍙nterfaceA錛?br /> public interface InterfaceA {
void methodA();
}
綾籆lassA瀹炵幇鎺ュ彛InterfaceA銆?br /> public class ClassA {
public void methodA() {
System.out.println("methodA of ClassA implements InterfaceA");
}
}
濡傛灉鏄娊璞＄被瀹炵幇涓涓帴鍙ｏ紝閭ｄ箞鎶借薄綾諱腑鍙互涓嶅叿浣撳疄鐜版帴鍙ｇ殑鏂規硶錛堜繚鎸佸叾鎶借薄鎬э級錛岃岀敱鍏跺瓙綾誨幓瀹炵幇銆?br /> 鎶借薄綾籆lassB瀹炵幇鎺ュ彛InterfaceA錛屼絾鏄病鏈夊叿浣撳疄鐜版柟娉昺ethodA()錛?br /> public abstract class ClassB {
}
瀛愮被ClassBSub瀹炵幇鎺ュ彛InterfaceA錛屼絾鏄病鏈夊叿浣撳疄鐜版柟娉昺ethodA()錛?br /> public class ClassBSub {
public void methodA() {
System.out.println("methodA of ClassBSub the subclass of ClassB");
}
}
鎺ュ彛鍜屾娊璞＄被鏄捐憲鐨勫叡鍚岀偣鏄帴鍙ｅ拰鎶借薄綾婚兘鍙互鏈夋娊璞℃柟娉曘?br /> 鎺ュ彛鍜屾娊璞＄被鐨勪笉鍚岀偣鏈夛細
(1)鎶借薄綾誨彲浠ユ湁瀹炰緥鍙橀噺錛岃屾帴鍙ｄ笉鑳芥嫢鏈夊疄渚嬪彉閲忥紝鎺ュ彛涓殑鍙橀噺閮芥槸闈欐侊紙static錛夌殑甯擱噺錛坒inal錛夈?br /> (2)鎶借薄綾誨彲浠ユ湁闈炴娊璞℃柟娉曪紝鑰屾帴鍙ｅ彧鑳芥湁鎶借薄鏂規硶銆?br /> java涓紝綾諱笌綾諱箣闂存槸涓嶈兘澶氱戶鎵跨殑銆俲ava涔嬫墍浠ョ姝㈢被涓庣被涔嬮棿鐨勫緇ф壙鏄洜涓哄緇ф壙鏈夊緢澶х殑緙虹偣銆?br /> 澶氱戶鎵胯櫧鐒惰兘浣垮瓙綾誨悓鏃舵嫢鏈夊涓埗綾葷殑鐗瑰緛錛屼絾鏄叾緙虹偣涔熸槸寰堟樉钁楃殑錛屼富瑕佹湁涓ゆ柟闈細
(1)濡傛灉鍦ㄤ竴涓瓙綾葷戶鎵跨殑澶氫釜鐖剁被涓嫢鏈夌浉鍚屽悕瀛楃殑瀹炰緥鍙橀噺錛屽瓙綾誨湪寮曠敤璇ュ彉閲忔椂灝嗕駭鐢熸涔夛紝鏃犳硶鍒ゆ柇搴旇浣跨敤鍝釜鐖剁被鐨勫彉閲忋備緥濡傦細
綾籆lassA錛?br /> public class ClassA {
protected int varSame = 0;
}
綾籆lassB錛?br /> public class ClassB {
protected int varSame = 1;
}
瀛愮被ClassC錛氾紙鍋囪鍏佽綾諱笌綾諱箣闂村緇ф壙錛?br /> public class ClassC extends ClassA, ClassB {
public void printOut() {
System.out.println(super.varSame);
}
public static void main(String[] args) {
ClassC classC = new ClassC();
classC.printOut();
}
}
涓婇潰紼嬪簭鐨勮繍琛岀粨鏋滀細鏄粈涔堝憿錛熻緭鍑?榪樻槸1錛?br /> (2)濡傛灉鍦ㄤ竴涓瓙綾葷戶鎵跨殑澶氫釜鐖剁被涓嫢鏈夌浉鍚屾柟娉曪紝瀛愮被涓湁娌℃湁瑕嗙洊璇ユ柟娉曪紝閭ｄ箞璋冪敤璇ユ柟娉曟椂灝嗕駭鐢熸涔夛紝鏃犳硶鍒ゆ柇搴旇璋冪敤鍝釜鐖剁被鐨勬柟娉曘備緥濡傦細
綾籆lassA錛?br /> public class ClassA {
public void printOut() {
System.out.println(0);
}
}
綾籆lassB錛?br /> public class ClassB {
public void printOut() {
System.out.println(1);
}
}
瀛愮被ClassC錛氾紙鍋囪鍏佽綾諱笌綾諱箣闂村緇ф壙錛?br /> public class ClassC extends ClassA, ClassB {
public static void main(String[] args) {
ClassA classA = new ClassC();
classA.printOut(); ------------------------- A琛?br /> ClassB classB = new ClassC();
classB.printOut(); ------------------------- B琛?br /> ClassC classC = new ClassC();
classC.printOut(); ------------------------- C琛?br /> }
}
涓婇潰紼嬪簭鐨勮繍琛岀粨鏋滀細鏄粈涔堝憿錛烝銆丅銆丆涓夎鐨勮緭鍑烘槸0榪樻槸1錛?br /> 姝ｅ洜涓烘湁浠ヤ笂鐨勮嚧鍛界己鐐癸紝鎵浠ava涓姝竴涓被緇ф壙澶氫釜鐖剁被錛涗絾鏄垢榪愮殑鏄痡ava鎻愪緵浜嗘帴鍙ｏ紝騫惰兘閫氳繃鎺ュ彛鐨勫姛鑳借幏寰楀緇ф壙鐨勮澶氫紭鐐硅屽張鎽掑純浜嗙被涓庣被澶氱戶鎵跨殑緙虹偣銆?br /> java鍏佽涓涓帴鍙ｇ戶鎵垮涓埗鎺ュ彛錛屼篃鍏佽涓涓被瀹炵幇澶氫釜鎺ュ彛錛岃岃繖鏍風殑澶氱戶鎵挎湁涓婇潰鎻愬埌鐨勭己鐐歸┈錛?br /> 絳旀鏄病鏈夛紝榪欐槸鐢辨帴鍙ｇ殑鎶借薄鎬у喅瀹氱殑銆?br /> 姝ｅ鍓嶉潰浠嬬粛鐨勶紝鍦ㄦ帴鍙ｄ腑涓嶈兘鏈夊疄渚嬪彉閲忥紝鍙兘鏈夐潤鎬佺殑甯擱噺錛屼笉鑳芥湁鍏蜂綋鐨勬柟娉曪紙鍖呭惈鏂規硶浣擄級錛屽彧鑳芥湁鎶借薄鏂規硶錛屽洜姝や篃灝辨憭寮冧簡澶氱戶鎵跨殑緙虹偣銆?br /> 瀵逛簬涓涓被瀹炵幇澶氫釜鎺ュ彛鐨勬儏鍐碉紝鍥犱負鎺ュ彛鍙湁鎶借薄鏂規硶錛屽叿浣撴柟娉曞彧鑳界敱瀹炵幇鎺ュ彛鐨勭被瀹炵幇錛屽湪璋冪敤鐨勬椂鍊欏緇堝彧浼氳皟鐢ㄥ疄鐜扮被鐨勬柟娉曪紙涓嶅瓨鍦ㄦ涔夛級錛屽洜姝や笉瀛樺湪澶氱戶鎵跨殑絎簩涓己鐐癸紱鑰屽張鍥犱負鎺ュ彛鍙湁闈欐佺殑甯擱噺錛屼絾鏄敱浜庨潤鎬佸彉閲忔槸鍦ㄧ紪璇戞湡鍐沖畾璋冪敤鍏崇郴鐨勶紝鍗充嬌瀛樺湪涓瀹氱殑鍐茬獊涔熶細鍦ㄧ紪璇戞椂鎻愮ず鍑洪敊錛涜屽紩鐢ㄩ潤鎬佸彉閲忎竴鑸洿鎺ヤ嬌鐢ㄧ被鍚嶆垨鎺ュ彛鍚嶏紝浠庤岄伩鍏嶄駭鐢熸涔夛紝鍥犳涔熶笉瀛樺湪澶氱戶鎵跨殑絎竴涓己鐐廣?br /> 瀵逛簬涓涓帴鍙ｇ戶鎵垮涓埗鎺ュ彛鐨勬儏鍐典篃涓鏍蜂笉瀛樺湪榪欎簺緙虹偣銆?br /> 璇風湅浠ヤ笅紺轟緥銆?br /> 鎺ュ彛A錛?br /> public interface InterfaceA {
int len = 1;
void output();
}
鎺ュ彛B錛?br /> public interface InterfaceB {
int len = 2;
void output();
}
鎺ュ彛Sub緇ф壙鎺ュ彛A鍜屾帴鍙錛?br /> public interface InterfaceSub extends InterfaceA, interfaceB {
}
綾籜yz瀹炵幇鎺ュ彛Sub錛?br /> public class Xyz implements InterfaceSub {
public void output() {
System.out.println("output in class Xyz.");
}
public void outputLen(int type) {
switch(type) {
case InterfaceA.len:
System.out.println("len of InterfaceA=."+type);
break;
case InterfaceB.len:
System.out.println("len of InterfaceB=."+type);
break;
}
}
public static void main(String[] args) {
Xyz xyz= new Xyz ();
xyz .output();
xyz .outputLen();
}
}
浠ヤ笂浠ｇ爜涓嶅瓨鍦ㄤ粈涔堥棶棰橈紝浣嗘槸濡傛灉璇曞浘緙栧啓浠ヤ笅瀛樺湪鍐茬獊鐨勪唬鐮侊紝鍒欎細緙栬瘧澶辮觸銆?br /> Xyz xyz = new Xyz();
int len = xyz.len;
System.out.println(len);
鐢變簬寮曞叆浜嗘帴鍙ｏ紝java鏄懼緱闈炲父鐏墊椿錛屼篃浣垮緱java涓殑澶氭佹ф洿鍔犲瘜鏈夐瓟鍔涖?br />
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