188W+绋嬪簭鍛樺叧娉ㄨ繃鐨勯棶棰橈細Java鍒板簳鏄�间紶閫掕繕鏄紩鐢ㄤ紶閫掞紵

鍦ㄩ�� Stack Overflow 鐨勬椂鍊欙紝鍙戠幇浜嗕竴浜涜闂噺鍍忛樋灏斿崙鏂北涓�鏍烽珮鐨勯棶棰橈紝姣斿璇磋繖涓細Java 鍒板簳鏄�间紶閫掕繕鏄紩鐢ㄤ紶閫掞紵璁块棶閲忚冻瓒虫湁 188涓�+锛岃繖涓嶅緱浜嗗晩锛佽鏄庢湁寰堝寰堝鐨勭▼搴忓憳琚繖涓棶棰樺洶鎵拌繃銆傚疄璇濆疄璇村惂锛�鎴�灏辨槸鍏朵腑涔嬩竴銆�

鏉ュ洖椤句竴涓嬫彁闂�呯殑闂锛�

鎴戜竴鐩磋涓� Java 鏄寜寮曠敤浼犻�掔殑锛屼絾鏄垜鐪嬩竴浜涘崥瀹笂璇翠笉鏄殑銆傛垜灏辩撼闂蜂簡锛孞ava 鍒板簳鏄�间紶閫掕繕鏄紩鐢ㄤ紶閫掞紵鍊间紶閫掑拰寮曠敤浼犻�掓湁浠�涔堝尯鍒憿锛�

濡傛灉浣犱篃鏇捐杩欎釜闂鍥版壈杩囷紝鎴栬�呮鍦ㄨ鍥版壈锛屽氨璇烽殢鎴戜竴璧锋潵姊崇悊涓�涓嬮棶棰樼殑绛旀銆傛墦鎬繘闃跺柦锛�

01銆佸�间紶閫掑拰寮曠敤浼犻��

浠�涔堟槸鍊间紶閫掞紝浠�涔堟槸寮曠敤浼犻�掞紵鎴戜滑闇�瑕佸厛鎶婅繖涓や釜瀹氫箟鎼炴竻妤氾紝鎵嶈兘鎼炴竻妤� Java 鏄寜鍊间紶閫掕繕鏄寜寮曠敤浼犻�掋��

鍊间紶閫掞紙pass by value锛夋槸鎸囧湪璋冪敤鏂规硶鏃跺皢瀹炲弬澶嶅埗涓�浠戒紶閫掑埌鏂规硶涓紝杩欐牱褰撴柟娉曞褰㈠弬杩涜淇敼鏃朵笉浼氬奖鍝嶅埌瀹炲弬銆�

寮曠敤浼犻�掞紙pass by reference锛夋槸鎸囧湪璋冪敤鏂规硶鏃跺皢瀹炲弬鐨勫湴鍧�鐩存帴浼犻�掑埌鏂规硶涓紝閭ｄ箞鍦ㄦ柟娉曚腑瀵瑰舰鍙傛墍杩涜鐨勪慨鏀癸紝灏嗗奖鍝嶅埌瀹炲弬銆�

涓婇潰鏄瘮杈冨畼鏂圭殑瀹氫箟锛岃璧锋潵涓嶅厤鐢熺‖銆傚湪鎴戠湅鏉ワ紝鍊间紶閫掑拰寮曠敤浼犻�掔殑鍏抽敭鍖哄埆鏈変袱鐐癸細

1锛夎皟鐢ㄦ柟娉曟椂鏈夋病鏈夊瀹炲弬杩涜澶嶅埗銆�

2锛夋柟娉曞唴瀵瑰舰鍙傜殑淇敼浼氫笉浼氬奖鍝嶅埌瀹炲弬銆�

what锛熷�间紶閫掑拰寮曠敤浼犻�掕繕娌℃湁鎼炴竻妤氾紝鍙堟潵涓や釜鏂板悕璇嶏細瀹炲弬鍜屽舰鍙傘�傚埆鎬ワ紝鍒�ャ��

02銆佸疄鍙傚拰褰㈠弬

瀹炲弬鍜屽舰鍙傜悊瑙ｈ捣鏉ユ瘮鍊间紶閫掑拰寮曠敤浼犻�掑鏄撶殑澶氾紝鍓嶈�呭氨濂藉儚鏄竴鍏冧竴娆℃柟绋嬶紝鍚庤�呭氨鍍忔槸涓�鍏冧簩娆℃柟绋嬨��

褰㈠弬锛氬畾涔夋柟娉曞悕鍜屾柟娉曚綋鐨勬椂鍊欎娇鐢ㄧ殑鍙傛暟锛岀洰鐨勬槸鐢ㄦ潵鎺ユ敹璋冪敤璇ユ柟娉曟椂浼犲叆鐨勫弬鏁般��

瀹炲弬锛氬湪璋冪敤鏈夊弬鏂规硶鏃朵紶鍏ョ殑鍙傛暟锛屾柟娉曞悕鍚庨潰鐨勬嫭鍙蜂腑鐨勫弬鏁伴�氬父琚О涓衡�滃疄鍙傗�濄��

澶у搴旇閮藉啓杩団�渉ello world鈥濈▼搴忎簡锛屽氨鍍忎笅闈㈣繖鏍枫��

public class Cmower {
    public static void main(String[] args) {
        System.out.println("hello world");
    }
}

鍏朵腑 args 灏辩浉褰撲簬鏄舰鍙傦紝鑰屽瓧绗︿覆鈥渉ello world鈥濆氨鐩稿綋浜庢槸瀹炲弬銆傚鏋滆寰楄繖涓緥瀛愪笉瀹规槗鐞嗚В锛岄偅鍐嶆潵鐪嬩竴涓��

public class Cmower {
    public static void main(String[] args) {
        Cmower cmower = new Cmower();
        cmower.sop("娌夐粯鐜嬩簩");
    }

    public void sop(String name) {
        System.out.println("hello " + name);
    }
}

鍏朵腑鈥滄矇榛樼帇浜屸�濅负瀹炲弬锛涙湁鍙傛柟娉� sop(String name) 涓殑 name 涓哄舰鍙傘�傚舰鍙傚氨濂藉儚瀹炲弬涓庤璋冪敤鏂规硶涔嬮棿鐨勪竴涓ˉ姊侊紝鍚﹀垯璋冪敤鑰呮病娉曚紶閫掑弬鏁帮紝琚皟鐢ㄧ殑鏂规硶鏃犳硶鎺ユ敹鍙傛暟銆�

03銆佸熀鏈被鍨嬫槸鍊间紶閫掔殑

Java 涓殑鏁版嵁绫诲瀷鍙互鍒嗕负涓ょ锛屼竴绉嶆槸鍩烘湰绫诲瀷锛屼竴绉嶆槸寮曠敤绫诲瀷銆傛垜鐩镐俊澶у鍦ㄧ湅鏈瘒鏂囩珷涔嬪墠锛屽氨鑳藉杈炬垚杩欐牱涓�涓叡璇嗭細鍩烘湰绫诲瀷鏄�间紶閫掔殑銆傝繖涓�鐐规鏃犵枒闂��

public class Cmower {
    public static void main(String[] args) {
        Cmower cmower = new Cmower();
        int age = 18;
        cmower.sop(age);
        System.out.println("main 涓殑 age " + age);
    }

    public void sop(int age) {
        age = 28;
        System.out.println("sop 涓殑 age " + age);
    }
}

涓婇潰杩欐浠ｇ爜涓紝sop() 鏂规硶鐨勫疄鍙� age 涓� 18锛屽敖绠� sop() 鏂规硶鐨勫舰鍙傝淇敼涓� 28锛屼絾骞朵笉浼氬奖鍝嶅疄鍙傜殑鍊笺�傝繖涓�鐐瑰彲浠ヤ粠杈撳嚭缁撴灉涓姞浠ヨ瘉鏄庛��

sop 涓殑 age 28
main 涓殑 age 18

鍏蜂綋鐨勬墽琛岃繃绋嬪涓嬪浘鎵�绀恒��

04銆佸紩鐢ㄧ被鍨嬫槸鍊间紶閫掑悧锛�

澶у涔嬫墍浠ヤ笉纭畾 Java 鏄�间紶閫掔殑杩樻槸寮曠敤浼犻�掔殑锛屽師鍥犲氨鍑哄湪杩欎釜寮曠敤绫诲瀷涓婇潰銆傚崟浠庡瓧闈㈢殑鎰忔�濅笂灏卞鏄撴悶娣凤細寮曠敤绫诲瀷涓嶆槸寮曠敤浼犻�掗毦閬撹繕鏄�间紶閫掞紵

public class Cmower {
    private String name;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public static void main(String[] args) {
        Cmower cmower = new Cmower();
        cmower.setName("娌夐粯鐜嬩簩");
        cmower.sop(cmower);
        System.out.println("main 涓殑 cmower " + cmower.getName());
    }

    public void sop(Cmower cmower) {
        cmower.setName("娌夐粯鐜嬩笁");
        System.out.println("sop 涓殑 cmower " + cmower.getName());
    }
}

鍦� main() 鏂规硶涓紝鎴戜滑閫氳繃 new 鍏抽敭瀛楀垱寤轰簡涓�涓璞� cmower锛屽苟灏嗗叾 name 灞炴�ц缃负鈥滄矇榛樼帇浜屸�濓紱鐒跺悗灏嗗疄鍙� cmower 浼犻�掔粰 sop() 鏂规硶锛屽湪 sop() 鏂规硶涓皢褰㈠弬 cmower 鐨� name 灞炴�т慨鏀逛负鈥滄矇榛樼帇涓夆�濄�傝緭鍑虹粨鏋滄槸浠�涔堟牱瀛愬憿锛�

sop 涓殑 cmower 娌夐粯鐜嬩笁
main 涓殑 cmower 娌夐粯鐜嬩笁

鍛�锛佸疄鍙� cmower 鐨勫睘鎬� name 绔熺劧涓嶆槸鈥滄矇榛樼帇浜屸�濊�屾槸鈥滄矇榛樼帇涓夆�濅簡锛佺湅鐪嬶紝鐪嬬湅锛孞ava 涓嶆槸鍊间紶閫掑惂锛�

鍒�ュ埆鎬ャ�傛垜浠湪 main 鏂规硶涓拷鍔犲嚑琛屼唬鐮併��

Cmower cmower = new Cmower();
cmower.setName("娌夐粯鐜嬩簩");

Cmower old = cmower;
cmower.sop(cmower);
System.out.println("main 涓殑 cmower " + cmower.getName());

System.out.println(old == cmower);

old == cmower 浼氭槸 true 杩樻槸 false 鍛紵闂笂鐪肩潧鎯充竴鎯炽�傚鏋滃疄鍦ㄦ槸鎯充笉鍑猴紝鎶涗竴鏋氱‖甯佸惂锛屽弽姝ｄ笉鏄� true 灏辨槸 false銆傚亣濡傚紩鐢ㄧ被鍨嬫槸寮曠敤浼犻�掔殑锛屾牴鎹紩鐢ㄤ紶閫掔殑瀹氫箟锛堝舰鍙傜殑淇敼灏嗕細褰卞搷鍒板疄鍙傦級锛岄偅涔堢粨鏋滀竴瀹氬氨鏄� false銆�

鎴戜滑鏉ョ湅涓�涓嬭緭鍑虹粨鏋滐細

sop 涓殑 cmower 娌夐粯鐜嬩笁
main 涓殑 cmower 娌夐粯鐜嬩笁
true

true锛熷紑浠�涔堢帺绗戯紵

涓嶅ソ鎰忔�濓紝娌℃湁寮�鐜╃瑧銆侸ava 鐨勭‘鏄�间紶閫掔殑銆傚彧涓嶈繃锛屽紩鐢ㄧ被鍨嬪湪璋冪敤鏈夊弬鏂规硶鐨勬椂鍊欙紝浼犻�掔殑鏄璞＄殑寮曠敤锛屽苟涓嶆槸瀵硅薄鏈韩銆傝�屽璞＄殑寮曠敤鍦ㄤ紶閫掔殑杩囩▼涓苟娌℃湁鍙戠敓鏀瑰彉锛岃櫧鐒跺璞℃湰韬彂鐢熶簡鍙樺寲銆傚彲浠ラ�氳繃涓嬮潰杩欏箙鍥炬劅鍙椾竴涓嬨��

杩欎笅鐞嗚В浜嗗惂锛�

05銆佹�荤粨

鏉ョ湅涓嬮潰杩欐浠ｇ爜銆�

int age = 18;
String name = "娌夐粯鐜嬩簩";

age 鏄熀鏈被鍨嬶紝鎵�浠ュ�煎氨鐩存帴淇濆瓨鍦ㄥ彉閲忎腑锛涜�� name 鏄紩鐢ㄧ被鍨嬶紝鍙橀噺涓繚瀛樼殑鍙槸瀵硅薄鐨勫唴瀛樺湴鍧�锛岃繖绉嶅彉閲忎竴鑸О涔嬩负瀵硅薄鐨勫紩鐢ㄣ��

鍩烘湰绫诲瀷浣滀负鍙傛暟琚紶閫掓椂鑲畾鏄�间紶閫掞紱寮曠敤绫诲瀷浣滀负鍙傛暟琚紶閫掓椂涔熸槸鍊间紶閫掞紝鍙笉杩団�滃�尖�濅负瀵瑰簲鐨勫紩鐢ㄣ��

---

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