Posted Java鍚庣
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浼樿川鏂囩珷锛屽強鏃堕€佽揪
鏈変竴浜涢噸瑕佺殑璁捐鍘熷垯鍦ㄥ紑绡囧拰澶у鍒嗕韩涓嬶紝杩欎簺鍘熷垯灏嗚疮閫氬叏鏂囷細
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闈㈠悜鎺ュ彛缂栫▼锛岃€屼笉鏄潰鍚戝疄鐜般€傝繖涓緢閲嶈锛屼篃鏄紭闆呯殑銆佸彲鎵╁睍鐨勪唬鐮佺殑绗竴姝ワ紝杩欏氨涓嶉渶瑕佸璇翠簡鍚с€?/span> -
鑱岃矗鍗曚竴鍘熷垯銆傛瘡涓被閮藉簲璇ュ彧鏈変竴涓崟涓€鐨勫姛鑳斤紝骞朵笖璇ュ姛鑳藉簲璇ョ敱杩欎釜绫诲畬鍏ㄥ皝瑁呰捣鏉ャ€?/span> -
瀵逛慨鏀瑰叧闂紝瀵规墿灞曞紑鏀俱€傚淇敼鍏抽棴鏄锛屾垜浠緵杈涜嫤鑻﹀姞鐝啓鍑烘潵鐨勪唬鐮侊紝璇ュ疄鐜扮殑鍔熻兘鍜岃淇鐨?bug 閮藉畬鎴愪簡锛屽埆浜哄彲涓嶈兘璇存敼灏辨敼锛涘鎵╁睍寮€鏀惧氨姣旇緝濂界悊瑙ｄ簡锛屼篃灏辨槸璇村湪鎴戜滑鍐欏ソ鐨勪唬鐮佸熀纭€涓婏紝寰堝鏄撳疄鐜版墿灞曘€?/span>
鍒涘缓鍨嬫ā寮?/span>
绠€鍗曞伐鍘傛ā寮?/span>
public class FoodFactory {
public static Food makeFood(String name) {
if (name.equals("noodle")) {
Food noodle = new LanZhouNoodle();
noodle.addSpicy("more");
return noodle;
} else if (name.equals("chicken")) {
Food chicken = new HuangMenChicken();
chicken.addCondiment("potato");
return chicken;
} else {
return null;
}
}
}
鎴戜滑寮鸿皟鑱岃矗鍗曚竴鍘熷垯锛屼竴涓被鍙彁渚涗竴绉嶅姛鑳斤紝FoodFactory 鐨勫姛鑳藉氨鏄彧瑕佽礋璐ｇ敓浜у悇绉?Food銆?/span>
宸ュ巶妯″紡
绠€鍗曞伐鍘傛ā寮忓緢绠€鍗曪紝濡傛灉瀹冭兘婊¤冻鎴戜滑鐨勯渶瑕侊紝鎴戣寰楀氨涓嶈鎶樿吘浜嗐€備箣鎵€浠ラ渶瑕佸紩鍏ュ伐鍘傛ā寮忥紝鏄洜涓烘垜浠線寰€闇€瑕佷娇鐢ㄤ袱涓垨涓や釜浠ヤ笂鐨勫伐鍘傘€?/span>
public interface FoodFactory {
Food makeFood(String name);
}
public class ChineseFoodFactory implements FoodFactory {
@Override
public Food makeFood(String name) {
if (name.equals("A")) {
return new ChineseFoodA();
} else if (name.equals("B")) {
return new ChineseFoodB();
} else {
return null;
}
}
}
public class AmericanFoodFactory implements FoodFactory {
@Override
public Food makeFood(String name) {
if (name.equals("A")) {
return new AmericanFoodA();
} else if (name.equals("B")) {
return new AmericanFoodB();
} else {
return null;
}
}
}
public class APP {
public static void main(String[] args) {
// 鍏堥€夋嫨涓€涓叿浣撶殑宸ュ巶
FoodFactory factory = new ChineseFoodFactory();
// 鐢辩涓€姝ョ殑宸ュ巶浜х敓鍏蜂綋鐨勫璞★紝涓嶅悓鐨勫伐鍘傞€犲嚭涓嶄竴鏍风殑瀵硅薄
Food food = factory.makeFood("A");
}
}
铏界劧閮芥槸璋冪敤 makeFood("A") 鍒朵綔 A 绫婚鐗╋紝浣嗘槸锛屼笉鍚岀殑宸ュ巶鐢熶骇鍑烘潵鐨勫畬鍏ㄤ笉涓€鏍枫€?/span>
绗竴姝ワ紝鎴戜滑闇€瑕侀€夊彇鍚堥€傜殑宸ュ巶锛岀劧鍚庣浜屾鍩烘湰涓婂拰绠€鍗曞伐鍘備竴鏍枫€?/span>
鏍稿績鍦ㄤ簬锛屾垜浠渶瑕佸湪绗竴姝ラ€夊ソ鎴戜滑闇€瑕佺殑宸ュ巶銆傛瘮濡傦紝鎴戜滑鏈?LogFactory 鎺ュ彛锛屽疄鐜扮被鏈?FileLogFactory 鍜?KafkaLogFactory锛屽垎鍒搴斿皢鏃ュ織鍐欏叆鏂囦欢鍜屽啓鍏?Kafka 涓紝鏄剧劧锛屾垜浠鎴风绗竴姝ュ氨闇€瑕佸喅瀹氬埌搴曡瀹炰緥鍖?FileLogFactory 杩樻槸 KafkaLogFactory锛岃繖灏嗗喅瀹氫箣鍚庣殑鎵€鏈夌殑鎿嶄綔銆?/span>
鎶借薄宸ュ巶妯″紡
褰撴秹鍙婂埌浜у搧鏃?/strong>鐨勬椂鍊欙紝灏遍渶瑕佸紩鍏ユ娊璞″伐鍘傛ā寮忎簡銆?/span>
涓€涓粡鍏哥殑渚嬪瓙鏄€犱竴鍙扮數鑴戙€傛垜浠厛涓嶅紩鍏ユ娊璞″伐鍘傛ā寮忥紝鐪嬬湅鎬庝箞瀹炵幇銆?/span>
鍥犱负鐢佃剳鏄敱璁稿鐨勬瀯浠剁粍鎴愮殑锛屾垜浠皢 CPU 鍜屼富鏉胯繘琛屾娊璞★紝鐒跺悗 CPU 鐢?CPUFactory 鐢熶骇锛屼富鏉跨敱 MainBoardFactory 鐢熶骇锛岀劧鍚庯紝鎴戜滑鍐嶅皢 CPU 鍜屼富鏉挎惌閰嶈捣鏉ョ粍鍚堝湪涓€璧凤紝濡備笅鍥撅細
杩欎釜鏃跺€欑殑瀹㈡埛绔皟鐢ㄦ槸杩欐牱鐨勶細
// 寰楀埌 Intel 鐨?nbsp;CPU
CPUFactory cpuFactory = new IntelCPUFactory();
CPU cpu = intelCPUFactory.makeCPU();
// 寰楀埌 AMD 鐨勪富鏉?/span>
MainBoardFactory mainBoardFactory = new AmdMainBoardFactory();
MainBoard mainBoard = mainBoardFactory.make();
// 缁勮 CPU 鍜屼富鏉?/span>
Computer computer = new Computer(cpu, mainBoard);
鍗曠嫭鐪?CPU 宸ュ巶鍜屼富鏉垮伐鍘傦紝瀹冧滑鍒嗗埆鏄墠闈㈡垜浠鐨?span class="mq-250">宸ュ巶妯″紡銆傝繖绉嶆柟寮忎篃瀹规槗鎵╁睍锛屽洜涓鸿缁欑數鑴戝姞纭洏鐨勮瘽锛屽彧闇€瑕佸姞涓€涓?HardDiskFactory 鍜岀浉搴旂殑瀹炵幇鍗冲彲锛屼笉闇€瑕佷慨鏀圭幇鏈夌殑宸ュ巶銆?/span>
浣嗘槸锛岃繖绉嶆柟寮忔湁涓€涓棶棰橈紝閭ｅ氨鏄鏋?nbsp;Intel 瀹朵骇鐨?CPU 鍜?AMD 浜х殑涓绘澘涓嶈兘鍏煎浣跨敤锛岄偅涔堣繖浠ｇ爜灏卞鏄撳嚭閿欙紝鍥犱负瀹㈡埛绔苟涓嶇煡閬撳畠浠笉鍏煎锛屼篃灏变細閿欒鍦板嚭鐜伴殢鎰忕粍鍚堛€?/span>
褰撴秹鍙婂埌杩欑浜у搧鏃忕殑闂鐨勬椂鍊欙紝灏遍渶瑕佹娊璞″伐鍘傛ā寮忔潵鏀寔浜嗐€傛垜浠笉鍐嶅畾涔?CPU 宸ュ巶銆佷富鏉垮伐鍘傘€佺‖鐩樺伐鍘傘€佹樉绀哄睆宸ュ巶绛夌瓑锛屾垜浠洿鎺ュ畾涔夌數鑴戝伐鍘傦紝姣忎釜鐢佃剳宸ュ巶璐熻矗鐢熶骇鎵€鏈夌殑璁惧锛岃繖鏍疯兘淇濊瘉鑲畾涓嶅瓨鍦ㄥ吋瀹归棶棰樸€?/span>
杩欎釜鏃跺€欙紝瀵逛簬瀹㈡埛绔潵璇达紝涓嶅啀闇€瑕佸崟鐙寫閫?CPU鍘傚晢銆佷富鏉垮巶鍟嗐€佺‖鐩樺巶鍟嗙瓑锛岀洿鎺ラ€夋嫨涓€瀹跺搧鐗屽伐鍘傦紝鍝佺墝宸ュ巶浼氳礋璐ｇ敓浜ф墍鏈夌殑涓滆タ锛岃€屼笖鑳戒繚璇佽偗瀹氭槸鍏煎鍙敤鐨勩€?/span>
public static void main(String[] args) {
// 绗竴姝ュ氨瑕侀€夊畾涓€涓€滃ぇ鍘傗€?/span>
ComputerFactory cf = new AmdFactory();
// 浠庤繖涓ぇ鍘傞€?nbsp;CPU
CPU cpu = cf.makeCPU();
// 浠庤繖涓ぇ鍘傞€犱富鏉?/span>
MainBoard board = cf.makeMainBoard();
// 浠庤繖涓ぇ鍘傞€犵‖鐩?/span>
HardDisk hardDisk = cf.makeHardDisk();
// 灏嗗悓涓€涓巶瀛愬嚭鏉ョ殑 CPU銆佷富鏉裤€佺‖鐩樼粍瑁呭湪涓€璧?/span>
Computer result = new Computer(cpu, board, hardDisk);
}
鍗曚緥妯″紡
public class Singleton {
// 棣栧厛锛屽皢 new Singleton() 鍫垫
private Singleton() {};
// 鍒涘缓绉佹湁闈欐€佸疄渚嬶紝鎰忓懗鐫€杩欎釜绫荤涓€娆′娇鐢ㄧ殑鏃跺€欏氨浼氳繘琛屽垱寤?/span>
private static Singleton instance = new Singleton();
public static Singleton getInstance() {
return instance;
}
// 鐬庡啓涓€涓潤鎬佹柟娉曘€傝繖閲屾兂璇寸殑鏄紝濡傛灉鎴戜滑鍙槸瑕佽皟鐢?Singleton.getDate(...)锛?/span>
// 鏈潵鏄笉鎯宠鐢熸垚 Singleton 瀹炰緥鐨勶紝涓嶈繃娌″姙娉曪紝宸茬粡鐢熸垚浜?/span>
public static Date getDate(String mode) {return new Date();}
}
寰堝浜洪兘鑳借鍑洪タ姹夋ā寮忕殑缂虹偣锛屽彲鏄垜瑙夊緱鐢熶骇杩囩▼涓紝寰堝皯纰板埌杩欑鎯呭喌锛氫綘瀹氫箟浜嗕竴涓崟渚嬬殑绫伙紝涓嶉渶瑕佸叾瀹炰緥锛屽彲鏄綘鍗存妸涓€涓垨鍑犱釜浣犱細鐢ㄥ埌鐨勯潤鎬佹柟娉曞鍒拌繖涓被涓€?/span>
public class Singleton {
// 棣栧厛锛屼篃鏄厛鍫垫 new Singleton() 杩欐潯璺?/span>
private Singleton() {}
// 鍜岄タ姹夋ā寮忕浉姣旓紝杩欒竟涓嶉渶瑕佸厛瀹炰緥鍖栧嚭鏉ワ紝娉ㄦ剰杩欓噷鐨?nbsp;volatile锛屽畠鏄繀椤荤殑
private static volatile Singleton instance = null;
public static Singleton getInstance() {
if (instance == null) {
// 鍔犻攣
synchronized (Singleton.class) {
// 杩欎竴娆″垽鏂篃鏄繀椤荤殑锛屼笉鐒朵細鏈夊苟鍙戦棶棰?/span>
if (instance == null) {
instance = new Singleton();
}
}
}
return instance;
}
}
鍙岄噸妫€鏌ワ紝鎸囩殑鏄袱娆℃鏌?instance 鏄惁涓?null銆?/span>
volatile 鍦ㄨ繖閲屾槸闇€瑕佺殑锛屽笇鏈涜兘寮曡捣璇昏€呯殑鍏虫敞銆?/span>
寰堝浜轰笉鐭ラ亾鎬庝箞鍐欙紝鐩存帴灏卞湪 getInstance() 鏂规硶绛惧悕涓婂姞涓?synchronized锛岃繖灏变笉澶氳浜嗭紝鎬ц兘澶樊銆?/span>
public class Singleton3 {
private Singleton3() {}
// 涓昏鏄娇鐢ㄤ簡 宓屽绫诲彲浠ヨ闂閮ㄧ被鐨勯潤鎬佸睘鎬у拰闈欐€佹柟娉?nbsp;鐨勭壒鎬?/span>
private static class Holder {
private static Singleton3 instance = new Singleton3();
}
public static Singleton3 getInstance() {
return Holder.instance;
}
}
娉ㄦ剰锛屽緢澶氫汉閮戒細鎶婅繖涓?span class="mq-447">宓屽绫?/strong>璇存垚鏄?span class="mq-448">闈欐€佸唴閮ㄧ被锛屼弗鏍煎湴璇达紝鍐呴儴绫诲拰宓屽绫绘槸涓嶄竴鏍风殑锛屽畠浠兘璁块棶鐨勫閮ㄧ被鏉冮檺涔熸槸涓嶄竴鏍风殑銆?/span>
寤洪€犺€呮ā寮?/span>
Food food = new FoodBuilder().a().b().c().build();
Food food = Food.builder().a().b().c().build();
濂楄矾灏辨槸鍏?new 涓€涓?Builder锛岀劧鍚庡彲浠ラ摼寮忓湴璋冪敤涓€鍫嗘柟娉曪紝鏈€鍚庡啀璋冪敤涓€娆?build() 鏂规硶锛屾垜浠渶瑕佺殑瀵硅薄灏辨湁浜嗐€?/span>
鏉ヤ竴涓腑瑙勪腑鐭╃殑寤洪€犺€呮ā寮忥細
class User {
// 涓嬮潰鏄€滀竴鍫嗏€濈殑灞炴€?/span>
private String name;
private String password;
private String nickName;
private int age;
// 鏋勯€犳柟娉曠鏈夊寲锛屼笉鐒跺鎴风灏变細鐩存帴璋冪敤鏋勯€犳柟娉曚簡
private User(String name, String password, String nickName, int age) {
this.name = name;
this.password = password;
this.nickName = nickName;
this.age = age;
}
// 闈欐€佹柟娉曪紝鐢ㄤ簬鐢熸垚涓€涓?nbsp;Builder锛岃繖涓笉涓€瀹氳鏈夛紝涓嶈繃鍐欒繖涓柟娉曟槸涓€涓緢濂界殑涔犳儻锛?/span>
// 鏈変簺浠ｇ爜瑕佹眰鍒汉鍐?nbsp;new User.UserBuilder().a()...build() 鐪嬩笂鍘诲氨娌￠偅涔堝ソ
public static UserBuilder builder() {
return new UserBuilder();
}
public static class UserBuilder {
// 涓嬮潰鏄拰 User 涓€妯′竴鏍风殑涓€鍫嗗睘鎬?/span>
private String name;
private String password;
private String nickName;
private int age;
private UserBuilder() {
}
// 閾惧紡璋冪敤璁剧疆鍚勪釜灞炴€у€硷紝杩斿洖 this锛屽嵆 UserBuilder
public UserBuilder name(String name) {
this.name = name;
return this;
}
public UserBuilder password(String password) {
this.password = password;
return this;
}
public UserBuilder nickName(String nickName) {
this.nickName = nickName;
return this;
}
public UserBuilder age(int age) {
this.age = age;
return this;
}
// build() 鏂规硶璐熻矗灏?UserBuilder 涓缃ソ鐨勫睘鎬р€滃鍒垛€濆埌 User 涓€?/span>
// 褰撶劧锛屽彲浠ュ湪 鈥滃鍒垛€?nbsp;涔嬪墠鍋氱偣妫€楠?/span>
public User build() {
if (name == null || password == null) {
throw new RuntimeException("鐢ㄦ埛鍚嶅拰瀵嗙爜蹇呭～");
}
if (age <= 0 || age >= 150) {
throw new RuntimeException("骞撮緞涓嶅悎娉?);
}
// 杩樺彲浠ュ仛璧嬩簣鈥濋粯璁ゅ€尖€滅殑鍔熻兘
if (nickName == null) {
nickName = name;
}
return new User(name, password, nickName, age);
}
}
}
鏍稿績鏄細鍏堟妸鎵€鏈夌殑灞炴€ч兘璁剧疆缁?Builder锛岀劧鍚?build() 鏂规硶鐨勬椂鍊欙紝灏嗚繖浜涘睘鎬?span class="mq-634">澶嶅埗缁欏疄闄呬骇鐢熺殑瀵硅薄銆?/span>
鐪嬬湅瀹㈡埛绔殑璋冪敤锛?/span>
public class APP {
public static void main(String[] args) {
User d = User.builder()
.name("foo")
.password("pAss12345")
.age(25)
.build();
}
}
璇村疄璇濓紝寤洪€犺€呮ā寮忕殑閾惧紡鍐欐硶寰堝惛寮曚汉锛屼絾鏄紝澶氬啓浜嗗緢澶氣€滄棤鐢ㄢ€濈殑 builder 鐨勪唬鐮侊紝鎰熻杩欎釜妯″紡娌′粈涔堢敤銆備笉杩囷紝褰撳睘鎬у緢澶氾紝鑰屼笖鏈変簺蹇呭～锛屾湁浜涢€夊～鐨勬椂鍊欙紝杩欎釜妯″紡浼氫娇浠ｇ爜娓呮櫚寰堝銆傛垜浠彲浠ュ湪 Builder 鐨勬瀯閫犳柟娉?/strong>涓己鍒惰璋冪敤鑰呮彁渚涘繀濉瓧娈碉紝杩樻湁锛屽湪 build() 鏂规硶涓牎楠屽悇涓弬鏁版瘮鍦?User 鐨勬瀯閫犳柟娉曚腑鏍￠獙锛屼唬鐮佽浼橀泤涓€浜涖€?/span>
棰樺璇濓紝寮虹儓寤鸿璇昏€呬娇鐢?lombok锛岀敤浜?lombok 浠ュ悗锛屼笂闈㈢殑涓€澶у爢浠ｇ爜浼氬彉鎴愬涓嬭繖鏍?
@Builder
class User {
private String name;
private String password;
private String nickName;
private int age;
}
鎬庝箞鏍凤紝鐪佷笅鏉ョ殑鏃堕棿鏄笉鏄張鍙互骞茬偣鍒殑浜嗐€?/span>
User user = new User().setName("").setPassword("").setAge(20);
寰堝浜烘槸杩欎箞鐢ㄧ殑锛屼絾鏄瑪鑰呰寰楀叾瀹炶繖绉嶅啓娉曢潪甯稿湴涓嶄紭闆咃紝涓嶆槸寰堟帹鑽愪娇鐢ㄣ€?/span>
鍘熷瀷妯″紡
鍘熷瀷妯″紡寰堢畝鍗曪細鏈変竴涓師鍨?span class="mq-708">瀹炰緥锛屽熀浜庤繖涓師鍨嬪疄渚嬩骇鐢熸柊鐨勫疄渚嬶紝涔熷氨鏄€滃厠闅嗏€濅簡銆?/span>
Object 绫讳腑鏈変竴涓?clone() 鏂规硶锛屽畠鐢ㄤ簬鐢熸垚涓€涓柊鐨勫璞★紝褰撶劧锛屽鏋滄垜浠璋冪敤杩欎釜鏂规硶锛宩ava 瑕佹眰鎴戜滑鐨勭被蹇呴』鍏?span class="mq-711">瀹炵幇 Cloneable 鎺ュ彛锛屾鎺ュ彛娌℃湁瀹氫箟浠讳綍鏂规硶锛屼絾鏄笉杩欎箞鍋氱殑璇濓紝鍦?clone() 鐨勬椂鍊欙紝浼氭姏鍑?CloneNotSupportedException 寮傚父銆?/span>
protected native Object clone() throws CloneNotSupportedException;
java 鐨勫厠闅嗘槸娴呭厠闅嗭紝纰板埌瀵硅薄寮曠敤鐨勬椂鍊欙紝鍏嬮殕鍑烘潵鐨勫璞″拰鍘熷璞′腑鐨勫紩鐢ㄥ皢鎸囧悜鍚屼竴涓璞°€傞€氬父瀹炵幇娣卞厠闅嗙殑鏂规硶鏄皢瀵硅薄杩涜搴忓垪鍖栵紝鐒跺悗鍐嶈繘琛屽弽搴忓垪鍖栥€?/span>
鍒涘缓鍨嬫ā寮忔€荤粨
缁撴瀯鍨嬫ā寮?/strong>
浠ｇ悊妯″紡
鐞嗚В浠ｇ悊杩欎釜璇嶏紝杩欎釜妯″紡鍏跺疄灏辩畝鍗曚簡銆?/span>
public interface FoodService {
Food makeChicken();
Food makeNoodle();
}
public class FoodServiceImpl implements FoodService {
public Food makeChicken() {
Food f = new Chicken()
f.setChicken("1kg");
f.setSpicy("1g");
f.setSalt("3g");
return f;
}
public Food makeNoodle() {
Food f = new Noodle();
f.setNoodle("500g");
f.setSalt("5g");
return f;
}
}
// 浠ｇ悊瑕佽〃鐜板緱鈥滃氨鍍忔槸鈥濈湡瀹炲疄鐜扮被锛屾墍浠ラ渶瑕佸疄鐜?nbsp;FoodService
public class FoodServiceProxy implements FoodService {
// 鍐呴儴涓€瀹氳鏈変竴涓湡瀹炵殑瀹炵幇绫伙紝褰撶劧涔熷彲浠ラ€氳繃鏋勯€犳柟娉曟敞鍏?/span>
private FoodService foodService = new FoodServiceImpl();
public Food makeChicken() {
System.out.println("鎴戜滑椹笂瑕佸紑濮嬪埗浣滈浮鑲変簡");
// 濡傛灉鎴戜滑瀹氫箟杩欏彞涓烘牳蹇冧唬鐮佺殑璇濓紝閭ｄ箞锛屾牳蹇冧唬鐮佹槸鐪熷疄瀹炵幇绫诲仛鐨勶紝
// 浠ｇ悊鍙槸鍦ㄦ牳蹇冧唬鐮佸墠鍚庡仛浜涒€滄棤瓒宠交閲嶁€濈殑浜嬫儏
Food food = foodService.makeChicken();
System.out.println("楦¤倝鍒朵綔瀹屾垚鍟︼紝鍔犵偣鑳℃绮?); // 澧炲己
food.addCondiment("pepper");
return food;
}
public Food makeNoodle() {
System.out.println("鍑嗗鍒朵綔鎷夐潰~");
Food food = foodService.makeNoodle();
System.out.println("鍒朵綔瀹屾垚鍟?)
return food;
}
}
瀹㈡埛绔皟鐢紝娉ㄦ剰锛屾垜浠鐢ㄤ唬鐞嗘潵瀹炰緥鍖栨帴鍙ｏ細
// 杩欓噷鐢ㄤ唬鐞嗙被鏉ュ疄渚嬪寲
FoodService foodService = new FoodServiceProxy();
foodService.makeChicken();
proxy
鎴戜滑鍙戠幇娌℃湁锛屼唬鐞嗘ā寮忚鐧戒簡灏辨槸鍋?nbsp;鈥滄柟娉曞寘瑁呪€?/strong> 鎴栧仛 鈥滄柟娉曞寮衡€?/strong>銆傚湪闈㈠悜鍒囬潰缂栫▼涓紝鍏跺疄灏辨槸鍔ㄦ€佷唬鐞嗙殑杩囩▼銆傛瘮濡?Spring 涓紝鎴戜滑鑷繁涓嶅畾涔変唬鐞嗙被锛屼絾鏄?Spring 浼氬府鎴戜滑鍔ㄦ€佹潵瀹氫箟浠ｇ悊锛岀劧鍚庢妸鎴戜滑瀹氫箟鍦?@Before銆丂After銆丂Around 涓殑浠ｇ爜閫昏緫鍔ㄦ€佹坊鍔犲埌浠ｇ悊涓€?/span>
閫傞厤鍣ㄦā寮?/span>
閫傞厤鍣ㄦā寮忓仛鐨勫氨鏄紝鏈変竴涓帴鍙ｉ渶瑕佸疄鐜帮紝浣嗘槸鎴戜滑鐜版垚鐨勫璞￠兘涓嶆弧瓒筹紝闇€瑕佸姞涓€灞傞€傞厤鍣ㄦ潵杩涜閫傞厤銆?/span>
榛樿閫傞厤鍣ㄦā寮?/span>
public interface FileAlterationListener {
void onStart(final FileAlterationObserver observer);
void onDirectoryCreate(final File directory);
void onDirectoryChange(final File directory);
void onDirectoryDelete(final File directory);
void onFileCreate(final File file);
void onFileChange(final File file);
void onFileDelete(final File file);
void onStop(final FileAlterationObserver observer);
}
姝ゆ帴鍙ｇ殑涓€澶ч棶棰樻槸鎶借薄鏂规硶澶浜嗭紝濡傛灉鎴戜滑瑕佺敤杩欎釜鎺ュ彛锛屾剰鍛崇潃鎴戜滑瑕佸疄鐜版瘡涓€涓娊璞℃柟娉曪紝濡傛灉鎴戜滑鍙槸鎯宠鐩戞帶鏂囦欢澶逛腑鐨?span class="mq-952">鏂囦欢鍒涘缓鍜?span class="mq-953">鏂囦欢鍒犻櫎浜嬩欢锛屽彲鏄垜浠繕鏄笉寰椾笉瀹炵幇鎵€鏈夌殑鏂规硶锛屽緢鏄庢樉锛岃繖涓嶆槸鎴戜滑鎯宠鐨勩€?/span>
public class FileAlterationListenerAdaptor implements FileAlterationListener {
public void onStart(final FileAlterationObserver observer) {
}
public void onDirectoryCreate(final File directory) {
}
public void onDirectoryChange(final File directory) {
}
public void onDirectoryDelete(final File directory) {
}
public void onFileCreate(final File file) {
}
public void onFileChange(final File file) {
}
public void onFileDelete(final File file) {
}
public void onStop(final FileAlterationObserver observer) {
}
}
姣斿鎴戜滑鍙互瀹氫箟浠ヤ笅绫伙紝鎴戜滑浠呬粎闇€瑕佸疄鐜版垜浠兂瀹炵幇鐨勬柟娉曞氨鍙互浜嗭細
public class FileMonitor extends FileAlterationListenerAdaptor {
public void onFileCreate(final File file) {
// 鏂囦欢鍒涘缓
doSomething();
}
public void onFileDelete(final File file) {
// 鏂囦欢鍒犻櫎
doSomething();
}
}
瀵硅薄閫傞厤鍣ㄦā寮?/span>
public interface Duck {
public void quack(); // 楦殑鍛卞懕鍙?/span>
public void fly(); // 椋?/span>
}
public interface Cock {
public void gobble(); // 楦＄殑鍜曞挄鍙?/span>
public void fly(); // 椋?/span>
}
public class WildCock implements Cock {
public void gobble() {
System.out.println("鍜曞挄鍙?);
}
public void fly() {
System.out.println("楦′篃浼氶鍝?);
}
}
楦帴鍙ｆ湁 fly() 鍜?quare() 涓や釜鏂规硶锛岄浮 Cock 濡傛灉瑕佸啋鍏呴腑锛宖ly() 鏂规硶鏄幇鎴愮殑锛屼絾鏄浮涓嶄細楦殑鍛卞懕鍙紝娌℃湁 quack() 鏂规硶銆傝繖涓椂鍊欏氨闇€瑕侀€傞厤浜嗭細
// 姣棤鐤戦棶锛岄鍏堬紝杩欎釜閫傞厤鍣ㄨ偗瀹氶渶瑕?nbsp;implements Duck锛岃繖鏍锋墠鑳藉綋鍋氶腑鏉ョ敤
public class CockAdapter implements Duck {
Cock cock;
// 鏋勯€犳柟娉曚腑闇€瑕佷竴涓浮鐨勫疄渚嬶紝姝ょ被灏辨槸灏嗚繖鍙浮閫傞厤鎴愰腑鏉ョ敤
public CockAdapter(Cock cock) {
this.cock = cock;
}
// 瀹炵幇楦殑鍛卞懕鍙柟娉?/span>
@Override
public void quack() {
// 鍐呴儴鍏跺疄鏄竴鍙浮鐨勫挄鍜曞彨
cock.gobble();
}
@Override
public void fly() {
cock.fly();
}
}
瀹㈡埛绔皟鐢ㄥ緢绠€鍗曚簡锛?/span>
public static void main(String[] args) {
// 鏈変竴鍙噹楦?/span>
Cock wildCock = new WildCock();
// 鎴愬姛灏嗛噹楦￠€傞厤鎴愰腑
Duck duck = new CockAdapter(wildCock);
...
}
鍒拌繖閲岋紝澶у涔熷氨鐭ラ亾浜嗛€傞厤鍣ㄦā寮忔槸鎬庝箞鍥炰簨浜嗐€傛棤闈炴槸鎴戜滑闇€瑕佷竴鍙腑锛屼絾鏄垜浠彧鏈変竴鍙浮锛岃繖涓椂鍊欏氨闇€瑕佸畾涔変竴涓€傞厤鍣紝鐢辫繖涓€傞厤鍣ㄦ潵鍏呭綋楦紝浣嗘槸閫傞厤鍣ㄩ噷闈㈢殑鏂规硶杩樻槸鐢遍浮鏉ュ疄鐜扮殑銆?/span>
鐒跺悗鏄竴绯诲垪瀹炵幇绫伙細 瀹氫箟涓€涓娊璞＄被锛屾绫荤殑瀹炵幇绫婚兘闇€瑕佷娇鐢?DrawAPI锛?/span> 瀹氫箟鎶借薄绫荤殑瀛愮被锛?/span> 鏈€鍚庯紝鎴戜滑鏉ョ湅瀹㈡埛绔紨绀猴細 鍙兘澶у鐪嬩笂闈竴姝ユ杩樹笉鏄壒鍒竻鏅帮紝鎴戞妸鎵€鏈夌殑涓滆タ鏁村悎鍒颁竴寮犲浘涓婏細 瑕佹妸瑁呴グ妯″紡璇存竻妤氭槑鐧斤紝涓嶆槸浠跺鏄撶殑浜嬫儏銆備篃璁歌鑰呯煡閬?nbsp;Java IO 涓殑鍑犱釜绫绘槸鍏稿瀷鐨勮楗版ā寮忕殑搴旂敤锛屼絾鏄鑰呬笉涓€瀹氭竻妤氬叾涓殑鍏崇郴锛屼篃璁哥湅瀹屽氨蹇樹簡锛屽笇鏈涚湅瀹岃繖鑺傚悗锛岃鑰呭彲浠ュ鍏舵湁鏇存繁鐨勬劅鎮熴€?/span> 鐒跺悗鏄笁涓熀纭€楗枡瀹炵幇绫伙紝绾㈣尪銆佺豢鑼跺拰鍜栧暋锛?/span> 瀹氫箟璋冩枡锛屼篃灏辨槸瑁呴グ鑰呯殑鍩虹被锛屾绫诲繀椤荤户鎵胯嚜 Beverage锛?/span> 鐒跺悗鎴戜滑鏉ュ畾涔夋煚妾€佽姃鏋滅瓑鍏蜂綋鐨勮皟鏂欙紝瀹冧滑灞炰簬瑁呴グ鑰咃紝姣棤鐤戦棶锛岃繖浜涜皟鏂欒偗瀹氶兘闇€瑕佺户鎵胯皟鏂?Condiment 绫伙細 鐪嬪鎴风璋冪敤锛?/span> 濡傛灉鎴戜滑闇€瑕?nbsp;鑺掓灉-鐝嶇彔-鍙屼唤鏌犳-绾㈣尪锛?/span> 鏄笉鏄緢鍙樻€侊紵 鐪嬬湅涓嬪浘鍙兘浼氭竻鏅颁竴浜涳細 FilterInputStream 鎵挎帴浜嗚楗版ā寮忕殑鍏抽敭鑺傜偣锛屽畠鐨勫疄鐜扮被鏄竴绯诲垪瑁呴グ鍣紝姣斿 BufferedInputStream 浠ｈ〃鐢ㄧ紦鍐叉潵瑁呴グ锛屼篃灏变娇寰楄緭鍏ユ祦鍏锋湁浜嗙紦鍐茬殑鍔熻兘锛孡ineNumberInputStream 浠ｈ〃鐢ㄨ鍙锋潵瑁呴グ锛屽湪鎿嶄綔鐨勬椂鍊欏氨鍙互鍙栧緱琛屽彿浜嗭紝DataInputStream 鐨勮楗帮紝浣垮緱鎴戜滑鍙互浠庤緭鍏ユ祦杞崲涓?java 涓殑鍩烘湰绫诲瀷鍊笺€?/span> 鎴戜滑搴旇鍍忎笅闈㈣繖鏍蜂娇鐢細 瀹氫箟鍑犱釜瀹炵幇绫伙細 瀹㈡埛绔皟鐢細 浠ヤ笂鏄垜浠父鍐欑殑浠ｇ爜锛屾垜浠渶瑕佺敾鍦嗗氨瑕佸厛瀹炰緥鍖栧渾锛岀敾闀挎柟褰㈠氨闇€瑕佸厛瀹炰緥鍖栦竴涓暱鏂瑰舰锛岀劧鍚庡啀璋冪敤鐩稿簲鐨?draw() 鏂规硶銆?/span> 涓嬮潰锛屾垜浠湅鐪嬫€庝箞鐢ㄩ棬闈㈡ā寮忔潵璁╁鎴风璋冪敤鏇村姞鍙嬪ソ涓€浜涖€?/span> 鐪嬬湅鐜板湪瀹㈡埛绔€庝箞璋冪敤锛?/span> 缁勫悎妯″紡鐢ㄤ簬琛ㄧず鍏锋湁灞傛缁撴瀯鐨勬暟鎹紝浣垮緱鎴戜滑瀵瑰崟涓璞″拰缁勫悎瀵硅薄鐨勮闂叿鏈変竴鑷存€с€?/span> 閫氬父锛岃繖绉嶇被闇€瑕佸畾涔?add(node)銆乺emove(node)銆乬etChildren() 杩欎簺鏂规硶銆?/span> 杩欒鐨勫叾瀹炲氨鏄粍鍚堟ā寮忥紝杩欑绠€鍗曠殑妯″紡鎴戝氨涓嶅仛杩囧浠嬬粛浜嗭紝鐩镐俊鍚勪綅璇昏€呬篃涓嶅枩娆㈢湅鎴戝啓搴熻瘽銆?/span> 澶嶇敤瀵硅薄鏈€绠€鍗曠殑鏂瑰紡鏄紝鐢ㄤ竴涓?HashMap 鏉ュ瓨鏀炬瘡娆℃柊鐢熸垚鐨勫璞°€傛瘡娆￠渶瑕佷竴涓璞＄殑鏃跺€欙紝鍏堝埌 HashMap 涓湅鐪嬫湁娌℃湁锛屽鏋滄病鏈夛紝鍐嶇敓鎴愭柊鐨勫璞★紝鐒跺悗灏嗚繖涓璞℃斁鍏?HashMap 涓€?/span> 杩欑绠€鍗曠殑浠ｇ爜鎴戝氨涓嶆紨绀轰簡銆?/span> 琛屼负鍨嬫ā寮忓叧娉ㄧ殑鏄悇涓被涔嬮棿鐨勭浉浜掍綔鐢紝灏嗚亴璐ｅ垝鍒嗘竻妤氾紝浣垮緱鎴戜滑鐨勪唬鐮佹洿鍔犲湴娓呮櫚銆?/span> 棣栧厛锛屽厛瀹氫箟涓€涓瓥鐣ユ帴鍙ｏ細 鐒跺悗鎴戜滑瀹氫箟鍏蜂綋鐨勫嚑涓瓥鐣ワ細 浣跨敤绛栫暐鐨勭被锛?/p>
瀹㈡埛绔紨绀猴細 鏀惧埌涓€寮犲浘涓婏紝璁╁ぇ瀹剁湅寰楁竻鏅颁簺锛?/span> 瑙傚療鑰呮ā寮忓浜庢垜浠潵璇达紝鐪熸槸鍐嶇畝鍗曚笉杩囦簡銆傛棤澶栦箮涓や釜鎿嶄綔锛岃瀵熻€呰闃呰嚜宸卞叧蹇冪殑涓婚鍜屼富棰樻湁鏁版嵁鍙樺寲鍚庨€氱煡瑙傚療鑰呬滑銆?/span> 瀹氫箟瑙傚療鑰呮帴鍙ｏ細 鍏跺疄濡傛灉鍙湁涓€涓瀵熻€呯被鐨勮瘽锛屾帴鍙ｉ兘涓嶇敤瀹氫箟浜嗭紝涓嶈繃锛岄€氬父鍦烘櫙涓嬶紝鏃㈢劧鐢ㄥ埌浜嗚瀵熻€呮ā寮忥紝鎴戜滑灏辨槸甯屾湜涓€涓簨浠跺嚭鏉ヤ簡锛屼細鏈夊涓笉鍚岀殑绫婚渶瑕佸鐞嗙浉搴旂殑淇℃伅銆傛瘮濡傦紝璁㈠崟淇敼鎴愬姛浜嬩欢锛屾垜浠笇鏈涘彂鐭俊鐨勭被寰楀埌閫氱煡銆佸彂閭欢鐨勭被寰楀埌閫氱煡銆佸鐞嗙墿娴佷俊鎭殑绫诲緱鍒伴€氱煡绛夈€?/span> 瀹㈡埛绔娇鐢ㄤ篃闈炲父绠€鍗曪細 output: 褰撶劧锛宩dk 涔熸彁渚涗簡鐩镐技鐨勬敮鎸侊紝鍏蜂綋鐨勫ぇ瀹跺彲浠ュ弬鑰?java.util.Observable 鍜?java.util.Observer 杩欎袱涓被銆?/span> 瀹為檯鐢熶骇杩囩▼涓紝瑙傚療鑰呮ā寮忓線寰€鐢ㄦ秷鎭腑闂翠欢鏉ュ疄鐜帮紝濡傛灉瑕佸疄鐜板崟鏈鸿瀵熻€呮ā寮忥紝绗旇€呭缓璁鑰呬娇鐢?Guava 涓殑 EventBus锛屽畠鏈夊悓姝ュ疄鐜颁篃鏈夊紓姝ュ疄鐜帮紝鏈枃涓昏浠嬬粛璁捐妯″紡锛屽氨涓嶅睍寮€璇翠簡銆?/span> 璐ｄ换閾鹃€氬父闇€瑕佸厛寤虹珛涓€涓崟鍚戦摼琛紝鐒跺悗璋冪敤鏂瑰彧闇€瑕佽皟鐢ㄥご閮ㄨ妭鐐瑰氨鍙互浜嗭紝鍚庨潰浼氳嚜鍔ㄦ祦杞笅鍘汇€傛瘮濡傛祦绋嬪鎵瑰氨鏄竴涓緢濂界殑渚嬪瓙锛屽彧瑕佺粓绔敤鎴锋彁浜ょ敵璇凤紝鏍规嵁鐢宠鐨勫唴瀹逛俊鎭紝鑷姩寤虹珛涓€鏉¤矗浠婚摼锛岀劧鍚庡氨鍙互寮€濮嬫祦杞簡銆?/span> 鎺ヤ笅鏉ワ紝鎴戜滑闇€瑕佸畾涔夊叿浣撶殑姣忎釜鑺傜偣浜嗐€?/span> 鏍￠獙鐢ㄦ埛鏄惁鏄柊鐢ㄦ埛锛?/span> 鏍￠獙鐢ㄦ埛鎵€鍦ㄥ湴鍖烘槸鍚﹀彲浠ュ弬涓庯細 鏍￠獙濂栧搧鏄惁宸查瀹岋細 瀹㈡埛绔細 妯℃澘鏂规硶涓皟鐢ㄤ簡 3 涓柟娉曪紝鍏朵腑 apply() 鏄娊璞℃柟娉曪紝瀛愮被蹇呴』瀹炵幇瀹冿紝鍏跺疄妯℃澘鏂规硶涓湁鍑犱釜鎶借薄鏂规硶瀹屽叏鏄嚜鐢辩殑锛屾垜浠篃鍙互灏嗕笁涓柟娉曢兘璁剧疆涓烘娊璞℃柟娉曪紝璁╁瓙绫绘潵瀹炵幇銆備篃灏辨槸璇达紝妯℃澘鏂规硶鍙礋璐ｅ畾涔夌涓€姝ュ簲璇ヨ鍋氫粈涔堬紝绗簩姝ュ簲璇ュ仛浠€涔堬紝绗笁姝ュ簲璇ュ仛浠€涔堬紝鑷充簬鎬庝箞鍋氾紝鐢卞瓙绫绘潵瀹炵幇銆?/span> 瀹㈡埛绔皟鐢ㄦ紨绀猴細 搴熻瘽鎴戝氨涓嶈浜嗭紝鎴戜滑璇翠竴涓畝鍗曠殑渚嬪瓙銆傚晢鍝佸簱瀛樹腑蹇冩湁涓渶鍩烘湰鐨勯渶姹傛槸鍑忓簱瀛樺拰琛ュ簱瀛橈紝鎴戜滑鐪嬬湅鎬庝箞鐢ㄧ姸鎬佹ā寮忔潵鍐欍€?/span> 鏍稿績鍦ㄤ簬锛屾垜浠殑鍏虫敞鐐逛笉鍐嶆槸 Context 鏄杩涜鍝鎿嶄綔锛岃€屾槸鍏虫敞鍦ㄨ繖涓?Context 浼氭湁鍝簺鎿嶄綔銆?/span> 瀹氫箟鍑忓簱瀛樼殑鐘舵€侊細 瀹氫箟琛ュ簱瀛樼姸鎬侊細 鍓嶉潰鐢ㄥ埌浜?context.setState(this)锛屾垜浠潵鐪嬬湅鎬庝箞瀹氫箟 Context 绫伙細 鎴戜滑鏉ョ湅涓嬪鎴风璋冪敤锛屽ぇ瀹跺氨涓€娓呬簩妤氫簡锛?/span> 以上是关于的主要内容，如果未能解决你的问题，请参考以下文章
涓婂浘搴旇杩樻槸寰堝鏄撶悊瑙ｇ殑锛屾垜灏变笉鍋氭洿澶氱殑瑙ｉ噴浜嗐€備笅闈紝鎴戜滑鐪嬬湅绫婚€傞厤妯″紡鎬庝箞鏍风殑銆?/span>
绫婚€傞厤鍣ㄦā寮?/span>
adapter-1
Target t = new SomeAdapter();
灏卞彲浠ヤ簡銆?/span>
閫傞厤鍣ㄦā寮忔€荤粨
妗ユ妯″紡
public interface DrawAPI {
public void draw(int radius, int x, int y);
}public class RedPen implements DrawAPI {
@Override
public void draw(int radius, int x, int y) {
System.out.println("鐢ㄧ孩鑹茬瑪鐢诲浘锛宺adius:" + radius + ", x:" + x + ", y:" + y);
}
}
public class GreenPen implements DrawAPI {
@Override
public void draw(int radius, int x, int y) {
System.out.println("鐢ㄧ豢鑹茬瑪鐢诲浘锛宺adius:" + radius + ", x:" + x + ", y:" + y);
}
}
public class BluePen implements DrawAPI {
@Override
public void draw(int radius, int x, int y) {
System.out.println("鐢ㄨ摑鑹茬瑪鐢诲浘锛宺adius:" + radius + ", x:" + x + ", y:" + y);
}
}public abstract class Shape {
protected DrawAPI drawAPI;
protected Shape(DrawAPI drawAPI) {
this.drawAPI = drawAPI;
}
public abstract void draw();
}// 鍦嗗舰
public class Circle extends Shape {
private int radius;
public Circle(int radius, DrawAPI drawAPI) {
super(drawAPI);
this.radius = radius;
}
public void draw() {
drawAPI.draw(radius, 0, 0);
}
}
// 闀挎柟褰?/span>
public class Rectangle extends Shape {
private int x;
private int y;
public Rectangle(int x, int y, DrawAPI drawAPI) {
super(drawAPI);
this.x = x;
this.y = y;
}
public void draw() {
drawAPI.draw(0, x, y);
}
}public static void main(String[] args) {
Shape greenCircle = new Circle(10, new GreenPen());
Shape redRectangle = new Rectangle(4, 8, new RedPen());
greenCircle.draw();
redRectangle.draw();
}
杩欏洖澶у搴旇灏辩煡閬撴娊璞″湪鍝噷锛屾€庝箞瑙ｈ€︿簡鍚с€傛ˉ姊佹ā寮忕殑浼樼偣涔熸槸鏄捐€屾槗瑙佺殑锛屽氨鏄潪甯稿鏄撹繘琛屾墿灞曘€?/span>
瑁呴グ妯″紡
鎴戜滑鏉ヨ璇磋楗版ā寮忕殑鍑哄彂鐐癸紝浠庡浘涓彲浠ョ湅鍒帮紝鎺ュ彛
Component
鍏跺疄宸茬粡鏈変簡
ConcreteComponentA
鍜?nbsp;
ConcreteComponentB
涓や釜瀹炵幇绫讳簡锛屼絾鏄紝濡傛灉鎴戜滑瑕?span class="mq-1522">澧炲己杩欎袱涓疄鐜扮被鐨勮瘽锛屾垜浠氨鍙互閲囩敤瑁呴グ妯″紡锛岀敤鍏蜂綋鐨勮楗板櫒鏉?span class="mq-1523">瑁呴グ瀹炵幇绫伙紝浠ヨ揪鍒板寮虹殑鐩殑銆?/span>
public abstract class Beverage {
// 杩斿洖鎻忚堪
public abstract String getDescription();
// 杩斿洖浠锋牸
public abstract double cost();
}public class BlackTea extends Beverage {
public String getDescription() {
return "绾㈣尪";
}
public double cost() {
return 10;
}
}
public class GreenTea extends Beverage {
public String getDescription() {
return "缁胯尪";
}
public double cost() {
return 11;
}
}
...// 鍜栧暋鐪佺暐// 璋冩枡
public abstract class Condiment extends Beverage {
}public class Lemon extends Condiment {
private Beverage bevarage;
// 杩欓噷寰堝叧閿紝闇€瑕佷紶鍏ュ叿浣撶殑楗枡锛屽闇€瑕佷紶鍏ユ病鏈夎瑁呴グ鐨勭孩鑼舵垨缁胯尪锛?/span>
// 褰撶劧涔熷彲浠ヤ紶鍏ュ凡缁忚楗板ソ鐨勮姃鏋滅豢鑼讹紝杩欐牱鍙互鍋氳姃鏋滄煚妾豢鑼?/span>
public Lemon(Beverage bevarage) {
this.bevarage = bevarage;
}
public String getDescription() {
// 瑁呴グ
return bevarage.getDescription() + ", 鍔犳煚妾?;
}
public double cost() {
// 瑁呴グ
return beverage.cost() + 2; // 鍔犳煚妾渶瑕?nbsp;2 鍏?/span>
}
}
public class Mango extends Condiment {
private Beverage bevarage;
public Mango(Beverage bevarage) {
this.bevarage = bevarage;
}
public String getDescription() {
return bevarage.getDescription() + ", 鍔犺姃鏋?;
}
public double cost() {
return beverage.cost() + 3; // 鍔犺姃鏋滈渶瑕?nbsp;3 鍏?/span>
}
}
...// 缁欐瘡涓€绉嶈皟鏂欓兘鍔犱竴涓被public static void main(String[] args) {
// 棣栧厛锛屾垜浠渶瑕佷竴涓熀纭€楗枡锛岀孩鑼躲€佺豢鑼舵垨鍜栧暋
Beverage beverage = new GreenTea();
// 寮€濮嬭楗?/span>
beverage = new Lemon(beverage); // 鍏堝姞涓€浠芥煚妾?/span>
beverage = new Mongo(beverage); // 鍐嶅姞涓€浠借姃鏋?/span>
System.out.println(beverage.getDescription() + " 浠锋牸锛氾骏" + beverage.cost());
//"缁胯尪, 鍔犳煚妾? 鍔犺姃鏋?nbsp;浠锋牸锛氾骏16"
}Beverage beverage = new Mongo(new Pearl(new Lemon(new Lemon(new BlackTea()))));
鍒拌繖閲岋紝澶у搴旇宸茬粡娓呮瑁呴グ妯″紡浜嗗惂銆?/span>
鎴戜滑鐭ラ亾 InputStream 浠ｈ〃浜嗚緭鍏ユ祦锛屽叿浣撶殑杈撳叆鏉ユ簮鍙互鏄枃浠讹紙FileInputStream锛夈€佺閬擄紙PipedInputStream锛夈€佹暟缁勶紙ByteArrayInputStream锛夌瓑锛岃繖浜涘氨鍍忓墠闈㈠ザ鑼剁殑渚嬪瓙涓殑绾㈣尪銆佺豢鑼讹紝灞炰簬鍩虹杈撳叆娴併€?/span>InputStream inputStream = new LineNumberInputStream(new BufferedInputStream(new FileInputStream("")));DataInputStream is = new DataInputStream(
new BufferedInputStream(
new FileInputStream("")));
闂ㄩ潰妯″紡
public interface Shape {
void draw();
}public class Circle implements Shape {
@Override
public void draw() {
System.out.println("Circle::draw()");
}
}
public class Rectangle implements Shape {
@Override
public void draw() {
System.out.println("Rectangle::draw()");
}
}public static void main(String[] args) {
// 鐢讳竴涓渾褰?/span>
Shape circle = new Circle();
circle.draw();
// 鐢讳竴涓暱鏂瑰舰
Shape rectangle = new Rectangle();
rectangle.draw();
}public class ShapeMaker {
private Shape circle;
private Shape rectangle;
private Shape square;
public ShapeMaker() {
circle = new Circle();
rectangle = new Rectangle();
square = new Square();
}
/**
* 涓嬮潰瀹氫箟涓€鍫嗘柟娉曪紝鍏蜂綋搴旇璋冪敤浠€涔堟柟娉曪紝鐢辫繖涓棬闈㈡潵鍐冲畾
*/
public void drawCircle(){
circle.draw();
}
public void drawRectangle(){
rectangle.draw();
}
public void drawSquare(){
square.draw();
}
}public static void main(String[] args) {
ShapeMaker shapeMaker = new ShapeMaker();
// 瀹㈡埛绔皟鐢ㄧ幇鍦ㄦ洿鍔犳竻鏅颁簡
shapeMaker.drawCircle();
shapeMaker.drawRectangle();
shapeMaker.drawSquare();
}缁勫悎妯″紡
public class Employee {
private String name;
private String dept;
private int salary;
private List<Employee> subordinates; // 涓嬪睘
public Employee(String name,String dept, int sal) {
this.name = name;
this.dept = dept;
this.salary = sal;
subordinates = new ArrayList<Employee>();
}
public void add(Employee e) {
subordinates.add(e);
}
public void remove(Employee e) {
subordinates.remove(e);
}
public List<Employee> getSubordinates(){
return subordinates;
}
public String toString(){
return ("Employee :[ Name : " + name + ", dept : " + dept + ", salary :" + salary+" ]");
}
}浜厓妯″紡
缁撴瀯鍨嬫ā寮忔€荤粨
琛屼负鍨嬫ā寮?/span>
绛栫暐妯″紡
public interface Strategy {
public void draw(int radius, int x, int y);
}public class RedPen implements Strategy {
@Override
public void draw(int radius, int x, int y) {
System.out.println("鐢ㄧ孩鑹茬瑪鐢诲浘锛宺adius:" + radius + ", x:" + x + ", y:" + y);
}
}
public class GreenPen implements Strategy {
@Override
public void draw(int radius, int x, int y) {
System.out.println("鐢ㄧ豢鑹茬瑪鐢诲浘锛宺adius:" + radius + ", x:" + x + ", y:" + y);
}
}
public class BluePen implements Strategy {
@Override
public void draw(int radius, int x, int y) {
System.out.println("鐢ㄨ摑鑹茬瑪鐢诲浘锛宺adius:" + radius + ", x:" + x + ", y:" + y);
}
}public class Context {
private Strategy strategy;
public Context(Strategy strategy){
this.strategy = strategy;
}
public int executeDraw(int radius, int x, int y){
return strategy.draw(radius, x, y);
}
}public static void main(String[] args) {
Context context = new Context(new BluePen()); // 浣跨敤缁胯壊绗旀潵鐢?/span>
context.executeDraw(10, 0, 0);
}
杩欎釜鏃跺€欙紝澶у鏈夋病鏈夎仈鎯冲埌缁撴瀯鍨嬫ā寮忎腑鐨勬ˉ姊佹ā寮忥紝瀹冧滑鍏跺疄闈炲父鐩镐技锛屾垜鎶婃ˉ姊佹ā寮忕殑鍥炬嬁杩囨潵澶у瀵规瘮涓嬶細
瑕佹垜璇寸殑璇濓紝瀹冧滑闈炲父鐩镐技锛屾ˉ姊佹ā寮忓湪宸︿晶鍔犱簡涓€灞傛娊璞¤€屽凡銆傛ˉ姊佹ā寮忕殑鑰﹀悎鏇翠綆锛岀粨鏋勬洿澶嶆潅涓€浜涖€?/span>
瑙傚療鑰呮ā寮?/span>
public class Subject {
private List<Observer> observers = new ArrayList<Observer>();
private int state;
public int getState() {
return state;
}
public void setState(int state) {
this.state = state;
// 鏁版嵁宸插彉鏇达紝閫氱煡瑙傚療鑰呬滑
notifyAllObservers();
}
// 娉ㄥ唽瑙傚療鑰?/span>
public void attach(Observer observer) {
observers.add(observer);
}
// 閫氱煡瑙傚療鑰呬滑
public void notifyAllObservers() {
for (Observer observer : observers) {
observer.update();
}
}
}public abstract class Observer {
protected Subject subject;
public abstract void update();
}public class BinaryObserver extends Observer {
// 鍦ㄦ瀯閫犳柟娉曚腑杩涜璁㈤槄涓婚
public BinaryObserver(Subject subject) {
this.subject = subject;
// 閫氬父鍦ㄦ瀯閫犳柟娉曚腑灏?nbsp;this 鍙戝竷鍑哄幓鐨勬搷浣滀竴瀹氳灏忓績
this.subject.attach(this);
}
// 璇ユ柟娉曠敱涓婚绫诲湪鏁版嵁鍙樻洿鐨勬椂鍊欒繘琛岃皟鐢?/span>
@Override
public void update() {
String result = Integer.toBinaryString(subject.getState());
System.out.println("璁㈤槄鐨勬暟鎹彂鐢熷彉鍖栵紝鏂扮殑鏁版嵁澶勭悊涓轰簩杩涘埗鍊间负锛? + result);
}
}
public class HexaObserver extends Observer {
public HexaObserver(Subject subject) {
this.subject = subject;
this.subject.attach(this);
}
@Override
public void update() {
String result = Integer.toHexString(subject.getState()).toUpperCase();
System.out.println("璁㈤槄鐨勬暟鎹彂鐢熷彉鍖栵紝鏂扮殑鏁版嵁澶勭悊涓哄崄鍏繘鍒跺€间负锛? + result);
}
}public static void main(String[] args) {
// 鍏堝畾涔変竴涓富棰?/span>
Subject subject1 = new Subject();
// 瀹氫箟瑙傚療鑰?/span>
new BinaryObserver(subject1);
new HexaObserver(subject1);
// 妯℃嫙鏁版嵁鍙樻洿锛岃繖涓椂鍊欙紝瑙傚療鑰呬滑鐨?nbsp;update 鏂规硶灏嗕細琚皟鐢?/span>
subject.setState(11);
}璁㈤槄鐨勬暟鎹彂鐢熷彉鍖栵紝鏂扮殑鏁版嵁澶勭悊涓轰簩杩涘埗鍊间负锛?011
璁㈤槄鐨勬暟鎹彂鐢熷彉鍖栵紝鏂扮殑鏁版嵁澶勭悊涓哄崄鍏繘鍒跺€间负锛欱璐ｄ换閾炬ā寮?/span>
public abstract class RuleHandler {
// 鍚庣户鑺傜偣
protected RuleHandler successor;
public abstract void apply(Context context);
public void setSuccessor(RuleHandler successor) {
this.successor = successor;
}
public RuleHandler getSuccessor() {
return successor;
}
}public class NewUserRuleHandler extends RuleHandler {
public void apply(Context context) {
if (context.isNewUser()) {
// 濡傛灉鏈夊悗缁ц妭鐐圭殑璇濓紝浼犻€掍笅鍘?/span>
if (this.getSuccessor() != null) {
this.getSuccessor().apply(context);
}
} else {
throw new RuntimeException("璇ユ椿鍔ㄤ粎闄愭柊鐢ㄦ埛鍙備笌");
}
}
}public class LocationRuleHandler extends RuleHandler {
public void apply(Context context) {
boolean allowed = activityService.isSupportedLocation(context.getLocation);
if (allowed) {
if (this.getSuccessor() != null) {
this.getSuccessor().apply(context);
}
} else {
throw new RuntimeException("闈炲父鎶辨瓑锛屾偍鎵€鍦ㄧ殑鍦板尯鏃犳硶鍙備笌鏈娲诲姩");
}
}
}public class LimitRuleHandler extends RuleHandler {
public void apply(Context context) {
int remainedTimes = activityService.queryRemainedTimes(context); // 鏌ヨ鍓╀綑濂栧搧
if (remainedTimes > 0) {
if (this.getSuccessor() != null) {
this.getSuccessor().apply(userInfo);
}
} else {
throw new RuntimeException("鎮ㄦ潵寰楀お鏅氫簡锛屽鍝佽棰嗗畬浜?);
}
}
}public static void main(String[] args) {
RuleHandler newUserHandler = new NewUserRuleHandler();
RuleHandler locationHandler = new LocationRuleHandler();
RuleHandler limitHandler = new LimitRuleHandler();
// 鍋囪鏈娲诲姩浠呮牎楠屽湴鍖哄拰濂栧搧鏁伴噺锛屼笉鏍￠獙鏂拌€佺敤鎴?/span>
locationHandler.setSuccessor(limitHandler);
locationHandler.apply(context);
}妯℃澘鏂规硶妯″紡
public abstract class AbstractTemplate {
// 杩欏氨鏄ā鏉挎柟娉?/span>
public void templateMethod() {
init();
apply(); // 杩欎釜鏄噸鐐?/span>
end(); // 鍙互浣滀负閽╁瓙鏂规硶
}
protected void init() {
System.out.println("init 鎶借薄灞傚凡缁忓疄鐜帮紝瀛愮被涔熷彲浠ラ€夋嫨瑕嗗啓");
}
// 鐣欑粰瀛愮被瀹炵幇
protected abstract void apply();
protected void end() {
}
}public class ConcreteTemplate extends AbstractTemplate {
public void apply() {
System.out.println("瀛愮被瀹炵幇鎶借薄鏂规硶 apply");
}
public void end() {
System.out.println("鎴戜滑鍙互鎶?nbsp;method3 褰撳仛閽╁瓙鏂规硶鏉ヤ娇鐢紝闇€瑕佺殑鏃跺€欒鍐欏氨鍙互浜?);
}
}public static void main(String[] args) {
AbstractTemplate t = new ConcreteTemplate();
// 璋冪敤妯℃澘鏂规硶
t.templateMethod();
}鐘舵€佹ā寮?/span>
public interface State {
public void doAction(Context context);
}public class DeductState implements State {
public void doAction(Context context) {
System.out.println("鍟嗗搧鍗栧嚭锛屽噯澶囧噺搴撳瓨");
context.setState(this);
//... 鎵ц鍑忓簱瀛樼殑鍏蜂綋鎿嶄綔
}
public String toString() {
return "Deduct State";
}
} public class RevertState implements State {
public void doAction(Context context) {
System.out.println("缁欐鍟嗗搧琛ュ簱瀛?);
context.setState(this);
//... 鎵ц鍔犲簱瀛樼殑鍏蜂綋鎿嶄綔
}
public String toString() {
return "Revert State";
}
}public class Context {
private State state;
private String name;
public Context(String name) {
this.name = name;
}
public void setState(State state) {
this.state = state;
}
public void getState() {
return this.state;
}
}public static void main(String[] args) {
// 鎴戜滑闇€瑕佹搷浣滅殑鏄?nbsp;iPhone X
Context context = new Context("iPhone X");
// 鐪嬬湅鎬庝箞杩涜琛ュ簱瀛樻搷浣?/span>
State revertState = new RevertState();
revertState.doAction(context);
// 鍚屾牱鐨勶紝鍑忓簱瀛樻搷浣滀篃闈炲父绠€鍗?/span>
State deductState = new DeductState();
deductState.doAction(context);
// 濡傛灉闇€瑕佹垜浠彲浠ヨ幏鍙栧綋鍓嶇殑鐘舵€?/span>
// context.getState().toString();
}琛屼负鍨嬫ā寮忔€荤粨
鎬荤粨