{"id":32166,"date":"2025-10-18T13:40:54","date_gmt":"2025-10-18T10:40:54","guid":{"rendered":"https:\/\/fatihsoysal.com\/blog\/?p=32166"},"modified":"2025-10-18T13:40:54","modified_gmt":"2025-10-18T10:40:54","slug":"java-singleton-siniflarinda-thread-guvenligi","status":"publish","type":"post","link":"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/","title":{"rendered":"Java Singleton S\u0131n\u0131flar\u0131nda Thread G\u00fcvenli\u011fi"},"content":{"rendered":"

<\/p>\n

Java Singleton S\u0131n\u0131flar\u0131nda Thread G\u00fcvenli\u011fi<\/h2>\n

Giri\u015f<\/h3>\n

Tekil Nesne (Singleton) tasar\u0131m deseni, bir s\u0131n\u0131f\u0131n yaln\u0131zca bir \u00f6rne\u011finin olu\u015fturulmas\u0131n\u0131 ve bu \u00f6rne\u011fe global bir eri\u015fim noktas\u0131n\u0131n sa\u011flanmas\u0131n\u0131 garanti eden yaz\u0131l\u0131m tasar\u0131m desenlerinden biridir. Bu desen, veritaban\u0131 ba\u011flant\u0131 havuzlar\u0131, yap\u0131land\u0131rma y\u00f6neticileri, g\u00fcnl\u00fckleyiciler veya sistem genelinde tek bir kayna\u011f\u0131n kontrol edilmesi gereken durumlar gibi senaryolarda yayg\u0131n olarak kullan\u0131l\u0131r. Amac\u0131, kaynak t\u00fcketimini optimize etmek, tutarl\u0131l\u0131\u011f\u0131 sa\u011flamak ve belirli bir nesnenin birden fazla kopyas\u0131n\u0131n olu\u015fturulmas\u0131ndan kaynaklanabilecek sorunlar\u0131 \u00f6nlemektir.<\/p>\n

Java gibi \u00e7oklu i\u015f par\u00e7ac\u0131\u011f\u0131 (multi-threaded) ortamlar\u0131nda, bir Singleton uygulamas\u0131n\u0131n thread g\u00fcvenli olmas\u0131 kritik \u00f6neme sahiptir. E\u011fer bir Singleton s\u0131n\u0131f\u0131 thread g\u00fcvenli bir \u015fekilde tasarlanmazsa, birden fazla i\u015f par\u00e7ac\u0131\u011f\u0131 ayn\u0131 anda s\u0131n\u0131f\u0131n \u00f6rne\u011fini olu\u015fturmaya \u00e7al\u0131\u015ft\u0131\u011f\u0131nda, beklenen tekil \u00f6rnek yerine birden fazla \u00f6rnek olu\u015fabilir. Bu durum, tasar\u0131m deseninin temel amac\u0131n\u0131 bozar ve uygulaman\u0131n beklenmedik davran\u0131\u015flar sergilemesine, veri tutars\u0131zl\u0131klar\u0131na veya performans sorunlar\u0131na yol a\u00e7abilir. Bu makalede, Java’daki \u00e7e\u015fitli Singleton uygulama yakla\u015f\u0131mlar\u0131n\u0131 inceleyecek, bunlar\u0131n thread g\u00fcvenli\u011fi \u00fczerindeki etkilerini analiz edecek ve en g\u00fcvenli ve verimli y\u00f6ntemleri tart\u0131\u015faca\u011f\u0131z.<\/p>\n

Temel Singleton Uygulamalar\u0131<\/h3>\n

Singleton deseni, genellikle s\u0131n\u0131f\u0131n yap\u0131c\u0131s\u0131n\u0131 (constructor) private<\/code> yaparak ve s\u0131n\u0131f\u0131n tek \u00f6rne\u011fini d\u00f6nd\u00fcren statik bir metot (genellikle getInstance()<\/code>) sa\u011flayarak uygulan\u0131r. Ancak, bu temel yap\u0131 i\u00e7inde bile, \u00f6rne\u011fin ne zaman olu\u015fturulaca\u011f\u0131na dair farkl\u0131 stratejiler mevcuttur.<\/p>\n

Aceleci Ba\u015flatma (Eager Initialization)<\/h4>\n

Aceleci ba\u015flatma, Singleton \u00f6rne\u011fini s\u0131n\u0131f y\u00fcklendi\u011fi anda olu\u015fturan en basit yakla\u015f\u0131md\u0131r. Bu y\u00f6ntem, \u00f6rne\u011fin her zaman ihtiya\u00e7 duyulaca\u011f\u0131 veya olu\u015fturulmas\u0131n\u0131n maliyetinin d\u00fc\u015f\u00fck oldu\u011fu durumlarda tercih edilebilir.<\/p>\n

public class EagerSingleton {\n    private static final EagerSingleton INSTANCE = new EagerSingleton();\n\n    private EagerSingleton() {\n        \/\/ Yap\u0131c\u0131 \u00f6zeldir\n    }\n\n    public static EagerSingleton getInstance() {\n        return INSTANCE;\n    }\n\n    public void showMessage() {\n        System.out.println(\"Merhaba, ben aceleci Singleton!\");\n    }\n}<\/code><\/pre>\n
Thread G\u00fcvenli\u011fi:<\/strong> Aceleci ba\u015flatma, do\u011fas\u0131 gere\u011fi thread g\u00fcvenlidir. Java Sanal Makinesi (JVM), bir s\u0131n\u0131f\u0131 y\u00fcklerken ve statik alanlar\u0131n\u0131 ba\u015flat\u0131rken t\u00fcm i\u015flemlerin thread g\u00fcvenli olmas\u0131n\u0131 garanti eder. INSTANCE<\/code> de\u011fi\u015fkeni, s\u0131n\u0131f y\u00fcklendi\u011fi anda yaln\u0131zca bir kez ba\u015flat\u0131l\u0131r ve bu i\u015flem, birden fazla i\u015f par\u00e7ac\u0131\u011f\u0131 ayn\u0131 anda eri\u015fmeye \u00e7al\u0131\u015fsa bile yaln\u0131zca bir kez ger\u00e7ekle\u015fir. Bu nedenle, ek bir senkronizasyon mekanizmas\u0131na gerek yoktur.<\/p>\n
Avantajlar\u0131:<\/strong>
\n*   Basit ve anla\u015f\u0131l\u0131r.
\n*   Do\u011fal olarak thread g\u00fcvenli.
\n*   \u00d6rnek her zaman kullan\u0131ma haz\u0131rd\u0131r.<\/p>\n
Dezavantajlar\u0131:<\/strong>
\n*   S\u0131n\u0131f y\u00fcklendi\u011fi anda \u00f6rnek olu\u015fturulur, bu da uygulaman\u0131n ba\u015flat\u0131lma s\u00fcresini art\u0131rabilir.
\n*   E\u011fer \u00f6rnek hi\u00e7bir zaman kullan\u0131lmayacaksa, kaynak israf\u0131na neden olabilir (\u00f6rne\u011fin bellek).<\/p>\n
Tembel Ba\u015flatma (Lazy Initialization)<\/h4>\n
Tembel ba\u015flatma, Singleton \u00f6rne\u011fini yaln\u0131zca ilk kez ihtiya\u00e7 duyuldu\u011funda olu\u015fturan bir yakla\u015f\u0131md\u0131r. Bu, kaynaklar\u0131n daha verimli kullan\u0131lmas\u0131n\u0131 sa\u011flar, \u00e7\u00fcnk\u00fc \u00f6rnek yaln\u0131zca gerekti\u011finde bellekte yer kaplar. Ancak, bu yakla\u015f\u0131m \u00e7oklu i\u015f par\u00e7ac\u0131\u011f\u0131 ortamlar\u0131nda ciddi thread g\u00fcvenli\u011fi sorunlar\u0131na yol a\u00e7abilir.<\/p>\n
Thread G\u00fcvenli Olmayan Tembel Ba\u015flatma<\/h5>\n
A\u015fa\u011f\u0131daki \u00f6rnek, tembel ba\u015flatman\u0131n thread g\u00fcvenli olmayan bir versiyonudur:<\/p>\n
public class NonThreadSafeLazySingleton {\n    private static NonThreadSafeLazySingleton instance;\n\n    private NonThreadSafeLazySingleton() {\n        \/\/ Yap\u0131c\u0131 \u00f6zeldir\n    }\n\n    public static NonThreadSafeLazySingleton getInstance() {\n        if (instance == null) { \/\/ (1)\n            instance = new NonThreadSafeLazySingleton(); \/\/ (2)\n        }\n        return instance;\n    }\n\n    public void showMessage() {\n        System.out.println(\"Merhaba, ben thread g\u00fcvenli olmayan tembel Singleton!\");\n    }\n}<\/code><\/pre>\n
Thread G\u00fcvenli\u011fi Sorunu:<\/strong> Bu uygulama, \u00e7oklu i\u015f par\u00e7ac\u0131\u011f\u0131 ortam\u0131nda thread g\u00fcvenli de\u011fildir. Varsayal\u0131m ki iki i\u015f par\u00e7ac\u0131\u011f\u0131 (Thread A<\/code> ve Thread B<\/code>) ayn\u0131 anda getInstance()<\/code> metodunu \u00e7a\u011f\u0131rd\u0131.
\n1.  Thread A<\/code>, if (instance == null)<\/code> kontrol\u00fcn\u00fc yapar ve instance<\/code> hen\u00fcz null<\/code> oldu\u011fu i\u00e7in ko\u015ful do\u011fru \u00e7\u0131kar.
\n2.  Thread A<\/code>, instance = new NonThreadSafeLazySingleton();<\/code> sat\u0131r\u0131na gelmeden ba\u011flam de\u011fi\u015ftirir (context switch) ve Thread B<\/code> \u00e7al\u0131\u015fmaya ba\u015flar.
\n3.  Thread B<\/code> de if (instance == null)<\/code> kontrol\u00fcn\u00fc yapar. instance<\/code> hala null<\/code> oldu\u011fu i\u00e7in ko\u015ful do\u011fru \u00e7\u0131kar.
\n4.  Thread B<\/code>, instance = new NonThreadSafeLazySingleton();<\/code> sat\u0131r\u0131n\u0131 \u00e7al\u0131\u015ft\u0131r\u0131r ve ilk Singleton \u00f6rne\u011fini olu\u015fturur.
\n5.  Thread B<\/code> i\u015fini bitirir ve Thread A<\/code> kald\u0131\u011f\u0131 yerden devam eder.
\n6.  Thread A<\/code> da instance = new NonThreadSafeLazySingleton();<\/code> sat\u0131r\u0131n\u0131 \u00e7al\u0131\u015ft\u0131r\u0131r ve ikinci bir Singleton \u00f6rne\u011fi olu\u015fturur.<\/p>\n
Sonu\u00e7 olarak, tek bir \u00f6rnek yerine iki farkl\u0131 Singleton \u00f6rne\u011fi olu\u015fturulmu\u015f olur. Bu, Singleton deseninin temel amac\u0131n\u0131 ihlal eder ve uygulaman\u0131n beklenmeyen davran\u0131\u015flar sergilemesine neden olabilir. Bu sorunu \u00e7\u00f6zmek i\u00e7in \u00e7e\u015fitli thread g\u00fcvenli tembel ba\u015flatma yakla\u015f\u0131mlar\u0131 geli\u015ftirilmi\u015ftir.<\/p>\n
Tembel Ba\u015flatmada Thread G\u00fcvenli\u011fini Sa\u011flama<\/h3>\n
Thread g\u00fcvenli olmayan tembel ba\u015flatma sorununu \u00e7\u00f6zmek i\u00e7in Java’da \u00e7e\u015fitli senkronizasyon mekanizmalar\u0131 kullan\u0131labilir.<\/p>\n
Senkronize Metot (Synchronized Method)<\/h4>\n
En basit thread g\u00fcvenli tembel ba\u015flatma \u00e7\u00f6z\u00fcmlerinden biri, getInstance()<\/code> metodunu synchronized<\/code> anahtar kelimesiyle i\u015faretlemektir. Bu, metodun ayn\u0131 anda yaln\u0131zca bir i\u015f par\u00e7ac\u0131\u011f\u0131 taraf\u0131ndan y\u00fcr\u00fct\u00fclebilece\u011fini garanti eder.<\/p>\n
public class SynchronizedSingleton {\n    private static SynchronizedSingleton instance;\n\n    private SynchronizedSingleton() {\n        \/\/ Yap\u0131c\u0131 \u00f6zeldir\n    }\n\n    public static synchronized SynchronizedSingleton getInstance() { \/\/ synchronized metot\n        if (instance == null) {\n            instance = new SynchronizedSingleton();\n        }\n        return instance;\n    }\n\n    public void showMessage() {\n        System.out.println(\"Merhaba, ben senkronize metot Singleton!\");\n    }\n}<\/code><\/pre>\n
Thread G\u00fcvenli\u011fi:<\/strong> synchronized<\/code> anahtar kelimesi, getInstance()<\/code> metodunun bir seferde yaln\u0131zca bir i\u015f par\u00e7ac\u0131\u011f\u0131 taraf\u0131ndan y\u00fcr\u00fct\u00fclmesini sa\u011flar. \u0130lk i\u015f par\u00e7ac\u0131\u011f\u0131 instance<\/code>‘\u0131 olu\u015fturduktan sonra, di\u011fer i\u015f par\u00e7ac\u0131klar\u0131 metoda eri\u015fmek i\u00e7in beklemek zorunda kal\u0131r ve instance<\/code> zaten olu\u015fturuldu\u011fu i\u00e7in null<\/code> kontrol\u00fcnden ge\u00e7ip mevcut \u00f6rne\u011fi d\u00f6nd\u00fcr\u00fcrler. Bu, birden fazla \u00f6rnek olu\u015fmas\u0131n\u0131 engeller.<\/p>\n
Avantajlar\u0131:<\/strong>
\n*   Uygulamas\u0131 kolay ve anla\u015f\u0131l\u0131r.
\n*   Tamamen thread g\u00fcvenli.<\/p>\n
Dezavantajlar\u0131:<\/strong>
\n*   Performans Overhead:<\/strong> \u00d6rnek bir kez olu\u015fturulduktan sonra bile, getInstance()<\/code> metodunun her \u00e7a\u011fr\u0131s\u0131nda senkronizasyon kilidi al\u0131n\u0131r ve serbest b\u0131rak\u0131l\u0131r. Bu, \u00f6zellikle y\u00fcksek e\u015fzamanl\u0131l\u0131k gerektiren uygulamalarda gereksiz performans d\u00fc\u015f\u00fc\u015f\u00fcne neden olabilir, \u00e7\u00fcnk\u00fc \u00f6rnek zaten mevcut oldu\u011funda senkronizasyona art\u0131k ihtiya\u00e7 duyulmaz.<\/p>\n
\u00c7ift Kontroll\u00fc Kilitleme (Double-Checked Locking – DCL)<\/h4>\n
Senkronize metodun performans sorununu gidermek i\u00e7in, yaln\u0131zca instance<\/code>‘\u0131n null<\/code> oldu\u011fu durumlarda senkronizasyon blo\u011funu kullanmay\u0131 ama\u00e7layan \u00c7ift Kontroll\u00fc Kilitleme (DCL) yakla\u015f\u0131m\u0131 geli\u015ftirilmi\u015ftir. Bu y\u00f6ntem, performans\u0131 art\u0131rmak i\u00e7in senkronizasyon maliyetini minimize etmeyi hedefler.<\/p>\n
public class DCLSingleton {\n    private static volatile DCLSingleton instance; \/\/ volatile anahtar kelimesi \u00f6nemli!\n\n    private DCLSingleton() {\n        \/\/ Yap\u0131c\u0131 \u00f6zeldir\n    }\n\n    public static DCLSingleton getInstance() {\n        if (instance == null) { \/\/ \u0130lk kontrol: E\u011fer \u00f6rnek zaten varsa, kilitlemeye gerek yok.\n            synchronized (DCLSingleton.class) { \/\/ Senkronize blok\n                if (instance == null) { \/\/ \u0130kinci kontrol: Kilidi ald\u0131ktan sonra tekrar kontrol et.\n                    instance = new DCLSingleton();\n                }\n            }\n        }\n        return instance;\n    }\n\n    public void showMessage() {\n        System.out.println(\"Merhaba, ben DCL Singleton!\");\n    }\n}<\/code><\/pre>\n
Thread G\u00fcvenli\u011fi ve volatile<\/code>:<\/strong> DCL, karma\u015f\u0131k bir konudur ve Java’n\u0131n bellek modeliyle yak\u0131ndan ili\u015fkilidir. Java 5’ten \u00f6nceki s\u00fcr\u00fcmlerde DCL, Instruction Reordering (talimat yeniden s\u0131ralama) nedeniyle sorunluydu. instance = new DCLSingleton();<\/code> i\u015flemi asl\u0131nda \u00fc\u00e7 ad\u0131m\u0131 i\u00e7erir:
\n1.  Bellek i\u00e7in DCLSingleton<\/code> nesnesine yer ayr\u0131l\u0131r.
\n2.  DCLSingleton<\/code> yap\u0131c\u0131s\u0131 \u00e7a\u011fr\u0131l\u0131r ve nesne ba\u015flat\u0131l\u0131r.
\n3.  instance<\/code> de\u011fi\u015fkeni, yeni olu\u015fturulan nesnenin bellekteki adresini g\u00f6sterecek \u015fekilde ayarlan\u0131r.<\/p>\n
JVM ve i\u015flemci, performans\u0131 art\u0131rmak i\u00e7in bu ad\u0131mlar\u0131n s\u0131ras\u0131n\u0131 de\u011fi\u015ftirebilir. E\u011fer 2. ad\u0131mdan \u00f6nce 3. ad\u0131m ger\u00e7ekle\u015firse (yani instance<\/code> yeni bellek adresini g\u00f6sterir ancak nesne hen\u00fcz tamamen ba\u015flat\u0131lmam\u0131\u015ft\u0131r), ve bir ba\u015fka i\u015f par\u00e7ac\u0131\u011f\u0131 instance<\/code>‘\u0131n null<\/code> olmad\u0131\u011f\u0131n\u0131 g\u00f6rerek ba\u015flat\u0131lmam\u0131\u015f nesneye eri\u015fmeye \u00e7al\u0131\u015f\u0131rsa NullPointerException<\/code> veya ba\u015fka hatalarla kar\u015f\u0131la\u015fabilir.<\/p>\n
volatile<\/code> anahtar kelimesi, Java 5 ve sonraki s\u00fcr\u00fcmlerde bu sorunu \u00e7\u00f6zer. volatile<\/code> bir de\u011fi\u015fken, her zaman ana bellekte okunur ve yaz\u0131l\u0131r, b\u00f6ylece t\u00fcm i\u015f par\u00e7ac\u0131klar\u0131n\u0131n en g\u00fcncel de\u011feri g\u00f6rmesi garanti edilir (memory visibility). Ayr\u0131ca, volatile<\/code> de\u011fi\u015fkenlere yap\u0131lan yazma i\u015flemleri ile ondan \u00f6nceki t\u00fcm yazma i\u015flemlerinin, volatile<\/code> de\u011fi\u015fkene yap\u0131lan okuma i\u015flemleri ile de ondan sonraki t\u00fcm okuma i\u015flemlerinin yeniden s\u0131ralanmas\u0131n\u0131 engeller (happens-before garantisi). Bu sayede, instance<\/code> de\u011fi\u015fkenine bir de\u011fer atand\u0131\u011f\u0131nda, o nesnenin tamamen ba\u015flat\u0131lm\u0131\u015f oldu\u011fu garanti edilir.<\/p>\n
Avantajlar\u0131:<\/strong>
\n*   Tembel ba\u015flatma sa\u011flar.
\n*   Senkronizasyon maliyetini yaln\u0131zca ilk \u00f6rnek olu\u015fturma s\u0131ras\u0131nda y\u00fckler, sonradan yap\u0131lan \u00e7a\u011fr\u0131larda kilitlemeye gerek kalmaz.
\n*   Performans a\u00e7\u0131s\u0131ndan senkronize metottan daha verimlidir.<\/p>\n
Dezavantajlar\u0131:<\/strong>
\n*   Uygulamas\u0131 daha karma\u015f\u0131kt\u0131r ve do\u011fru bir \u015fekilde uygulanmas\u0131 volatile<\/code> anahtar kelimesinin do\u011fru kullan\u0131m\u0131n\u0131 gerektirir.
\n*   Java 5 \u00f6ncesi s\u00fcr\u00fcmlerde g\u00fcvenilir de\u011fildi.<\/p>\n
\u0130stek \u00dczerine Tutucu S\u0131n\u0131f Deseni (Initialization-on-demand holder idiom)<\/h4>\n
Bu desen, Java’n\u0131n s\u0131n\u0131f y\u00fckleme mekanizmalar\u0131n\u0131 kullanarak tembel ba\u015flatmay\u0131 ve thread g\u00fcvenli\u011fini zarif bir \u015fekilde birle\u015ftirir. volatile<\/code> veya a\u00e7\u0131k synchronized<\/code> bloklar\u0131na ihtiya\u00e7 duymadan thread g\u00fcvenli\u011fi sa\u011flar.<\/p>\n
public class BillPughSingleton {\n    private BillPughSingleton() {\n        \/\/ Yap\u0131c\u0131 \u00f6zeldir\n    }\n\n    private static class SingletonHelper { \/\/ \u0130\u00e7 i\u00e7e statik yard\u0131mc\u0131 s\u0131n\u0131f\n        private static final BillPughSingleton INSTANCE = new BillPughSingleton();\n    }\n\n    public static BillPughSingleton getInstance() {\n        return SingletonHelper.INSTANCE;\n    }\n\n    public void showMessage() {\n        System.out.println(\"Merhaba, ben Bill Pugh Singleton!\");\n    }\n}<\/code><\/pre>\n
Thread G\u00fcvenli\u011fi:<\/strong> Bu desenin \u00e7al\u0131\u015fma prensibi, Java’n\u0131n s\u0131n\u0131f y\u00fckleme modeline dayan\u0131r. BillPughSingleton<\/code> s\u0131n\u0131f\u0131 y\u00fcklendi\u011finde, SingletonHelper<\/code> i\u00e7 i\u00e7e statik s\u0131n\u0131f\u0131 hen\u00fcz y\u00fcklenmez ve ba\u015flat\u0131lmaz. SingletonHelper<\/code> s\u0131n\u0131f\u0131 yaln\u0131zca getInstance()<\/code> metodu ilk kez \u00e7a\u011fr\u0131ld\u0131\u011f\u0131nda ve SingletonHelper.INSTANCE<\/code>‘a eri\u015fildi\u011finde JVM taraf\u0131ndan y\u00fcklenir.<\/p>\n
Java spesifikasyonuna g\u00f6re, bir s\u0131n\u0131f\u0131n statik ba\u015flat\u0131c\u0131lar\u0131 (static initializers) thread g\u00fcvenli bir \u015fekilde y\u00fcr\u00fct\u00fcl\u00fcr. Yani, SingletonHelper<\/code> s\u0131n\u0131f\u0131 y\u00fcklendi\u011finde ve INSTANCE<\/code> alan\u0131 ba\u015flat\u0131l\u0131rken, JVM bu i\u015flemin yaln\u0131zca bir kez ve thread g\u00fcvenli bir \u015fekilde ger\u00e7ekle\u015fmesini garanti eder. Bu sayede, birden fazla i\u015f par\u00e7ac\u0131\u011f\u0131 ayn\u0131 anda getInstance()<\/code> metodunu \u00e7a\u011f\u0131rsa bile, SingletonHelper<\/code> s\u0131n\u0131f\u0131 yaln\u0131zca bir kez y\u00fcklenir ve INSTANCE<\/code> da yaln\u0131zca bir kez olu\u015fturulur.<\/p>\n
Avantajlar\u0131:<\/strong>
\n*   Ger\u00e7ekten tembel ba\u015flatma sa\u011flar (lazy initialization).
\n*   Do\u011fal olarak thread g\u00fcvenlidir, a\u00e7\u0131k synchronized<\/code> anahtar kelimesine veya volatile<\/code>‘a ihtiya\u00e7 duymaz.
\n*   Basit, zarif ve okunabilir bir koddur.
\n*   Performans a\u00e7\u0131s\u0131ndan \u00e7ok verimlidir, \u00e7\u00fcnk\u00fc senkronizasyon maliyeti yoktur.<\/p>\n
Dezavantajlar\u0131:<\/strong>
\n*   Hemen hemen hi\u00e7bir dezavantaj\u0131 yoktur ve genellikle tembel ba\u015flatma i\u00e7in en iyi yakla\u015f\u0131mlardan biri olarak kabul edilir.<\/p>\n
Enum Singleton (Enum Singleton)<\/h4>\n
Java 5 ile tan\u0131t\u0131lan enum<\/code> (numaraland\u0131rma) tipi, Singleton desenini uygulamak i\u00e7in belki de en basit, en g\u00fcvenli ve en sa\u011flam yoldur.<\/p>\n
public enum EnumSingleton {\n    INSTANCE; \/\/ Tek \u00f6rnek\n\n    public void showMessage() {\n        System.out.println(\"Merhaba, ben Enum Singleton!\");\n    }\n}<\/code><\/pre>\n
Thread G\u00fcvenli\u011fi:<\/strong> Enum t\u00fcrleri, Java dil spesifikasyonu taraf\u0131ndan garanti edilen bir mekanizma ile thread g\u00fcvenli bir \u015fekilde ba\u015flat\u0131l\u0131r. Bir enum sabiti ilk kez eri\u015fildi\u011finde, JVM taraf\u0131ndan thread g\u00fcvenli bir \u015fekilde ba\u015flat\u0131l\u0131r. Bu, INSTANCE<\/code>‘\u0131n yaln\u0131zca bir kez ve do\u011fru bir \u015fekilde olu\u015fturulmas\u0131n\u0131 sa\u011flar.<\/p>\n
Di\u011fer Avantajlar\u0131:<\/strong>
\n*   Serile\u015ftirme Sorunlar\u0131n\u0131 Otomatik \u00c7\u00f6zme:<\/strong> Enum’lar, serile\u015ftirme ve ters serile\u015ftirme s\u0131ras\u0131nda yeni \u00f6rneklerin olu\u015fturulmas\u0131n\u0131 otomatik olarak engeller. readResolve()<\/code> metodunu override etmeye gerek kalmaz.
\n*   Yans\u0131ma Sald\u0131r\u0131lar\u0131na Kar\u015f\u0131 Diren\u00e7li:<\/strong> Enum yap\u0131c\u0131s\u0131n\u0131n private<\/code> olmas\u0131n\u0131n yan\u0131 s\u0131ra, Java yans\u0131ma API’si (Reflection API<\/code>) ile enum yap\u0131c\u0131s\u0131na eri\u015fmek ve birden fazla \u00f6rnek olu\u015fturmak m\u00fcmk\u00fcn de\u011fildir. Bu, di\u011fer Singleton uygulamalar\u0131n\u0131n zay\u0131f noktalar\u0131ndan biridir.
\n*   K\u0131sa ve \u00d6z Kod:<\/strong> \u00c7ok az kodla sa\u011flam bir Singleton sa\u011flar.<\/p>\n
Dezavantajlar\u0131:<\/strong>
\n*   Tembel Ba\u015flatma Derecesi:<\/strong> Enum sabiti, enum tipi ilk kez eri\u015fildi\u011finde ba\u015flat\u0131l\u0131r. Bu, Bill Pugh desenindeki gibi “ger\u00e7ek” tembel ba\u015flatma kadar esnek olmayabilir, \u00e7\u00fcnk\u00fc i\u00e7 i\u00e7e s\u0131n\u0131f\u0131n y\u00fcklenmesini tetikleyen belirli bir metot \u00e7a\u011fr\u0131s\u0131na ba\u011fl\u0131 de\u011fildir. Ancak \u00e7o\u011fu durumda bu seviyede tembel ba\u015flatma kabul edilebilir.
\n*   Karma\u015f\u0131k Ba\u015flatma Mant\u0131\u011f\u0131:<\/strong> E\u011fer Singleton \u00f6rne\u011finin ba\u015flat\u0131lmas\u0131 karma\u015f\u0131k mant\u0131k veya parametreler gerektiriyorsa, enum kullan\u0131m\u0131 biraz daha zorlay\u0131c\u0131 olabilir.<\/p>\n
Di\u011fer Singleton Zorluklar\u0131n\u0131 Ele Alma<\/h3>\n
Thread g\u00fcvenli\u011finin yan\u0131 s\u0131ra, Singleton deseninin sa\u011flaml\u0131\u011f\u0131n\u0131 etkileyen ba\u015fka fakt\u00f6rler de vard\u0131r: yans\u0131ma ve serile\u015ftirme.<\/p>\n
Yans\u0131ma Sald\u0131r\u0131lar\u0131 (Reflection Attacks)<\/h4>\n
Java Reflection API’si, \u00e7al\u0131\u015fma zaman\u0131nda bir s\u0131n\u0131f\u0131n \u00fcyelerine (alanlar, metotlar, yap\u0131c\u0131lar) eri\u015filmesini ve hatta private<\/code> olanlara bile m\u00fcdahale edilmesini sa\u011flar. Bu, bir Singleton s\u0131n\u0131f\u0131n\u0131n private<\/code> yap\u0131c\u0131s\u0131n\u0131 \u00e7a\u011f\u0131rarak birden fazla \u00f6rnek olu\u015fturmak i\u00e7in kullan\u0131labilir.<\/p>\n
\/\/ DCLSingleton \u00f6rne\u011fi \u00fczerinden yans\u0131ma sald\u0131r\u0131s\u0131\nDCLSingleton instance1 = DCLSingleton.getInstance();\nDCLSingleton instance2 = null;\n\ntry {\n    Constructor[] constructors = DCLSingleton.class.getDeclaredConstructors();\n    for (Constructor constructor : constructors) {\n        constructor.setAccessible(true); \/\/ Private yap\u0131c\u0131ya eri\u015fimi etkinle\u015ftir\n        instance2 = (DCLSingleton) constructor.newInstance();\n        break;\n    }\n} catch (Exception e) {\n    e.printStackTrace();\n}\n\nSystem.out.println(\"Instance 1 hashCode: \" + instance1.hashCode());\nSystem.out.println(\"Instance 2 hashCode: \" + instance2.hashCode());\n\/\/ Farkl\u0131 hash kodlar\u0131, farkl\u0131 \u00f6rnekler oldu\u011funu g\u00f6sterir<\/code><\/pre>\n
Bu sald\u0131r\u0131y\u0131 engellemenin bir yolu, yap\u0131c\u0131n\u0131n i\u00e7inde bir kontrol eklemektir:<\/p>\n
public class ReflectionSafeSingleton {\n    private static ReflectionSafeSingleton instance;\n\n    private ReflectionSafeSingleton() {\n        if (instance != null) {\n            throw new RuntimeException(\"Bu s\u0131n\u0131f\u0131n tekil \u00f6rne\u011fini olu\u015fturmak i\u00e7in getInstance() metodunu kullan\u0131n.\");\n        }\n    }\n    \/\/ ... getInstance() metodu DCL veya Bill Pugh gibi thread-safe bir \u015fekilde uygulan\u0131r\n}<\/code><\/pre>\n
Ancak, en kolay ve en sa\u011flam \u00e7\u00f6z\u00fcm yine enum<\/code> Singleton kullanmakt\u0131r, \u00e7\u00fcnk\u00fc enum yap\u0131c\u0131s\u0131na yans\u0131ma yoluyla eri\u015fmek m\u00fcmk\u00fcn de\u011fildir.<\/p>\n
Serile\u015ftirme Sorunlar\u0131 (Serialization Issues)<\/h4>\n
E\u011fer bir Singleton s\u0131n\u0131f\u0131 Serializable<\/code> aray\u00fcz\u00fcn\u00fc uyguluyorsa, serile\u015ftirme ve ters serile\u015ftirme (deserialization) i\u015flemleri s\u0131ras\u0131nda yeni bir \u00f6rnek olu\u015fturulabilir. Bir nesne serile\u015ftirildi\u011finde bellekteki durumu bir byte ak\u0131\u015f\u0131na d\u00f6n\u00fc\u015ft\u00fcr\u00fcl\u00fcr ve bu ak\u0131\u015f daha sonra ters serile\u015ftirilerek nesnenin yeni bir kopyas\u0131n\u0131 olu\u015fturabilir.<\/p>\n
\/\/ DCLSingleton'\u0131n serile\u015ftirilebilir oldu\u011funu varsayal\u0131m\npublic class DCLSingleton implements Serializable {\n    \/\/ ... \u00f6nceki kod\n    private static final long serialVersionUID = 1L;\n}\n\n\/\/ Serile\u015ftirme ve ters serile\u015ftirme\nDCLSingleton instance1 = DCLSingleton.getInstance();\nObjectOutput out = new ObjectOutputStream(new FileOutputStream(\"singleton.ser\"));\nout.writeObject(instance1);\nout.close();\n\nObjectInput in = new ObjectInputStream(new FileInputStream(\"singleton.ser\"));\nDCLSingleton instance2 = (DCLSingleton) in.readObject();\nin.close();\n\nSystem.out.println(\"Instance 1 hashCode: \" + instance1.hashCode());\nSystem.out.println(\"Instance 2 hashCode: \" + instance2.hashCode());\n\/\/ Farkl\u0131 hash kodlar\u0131, farkl\u0131 \u00f6rnekler oldu\u011funu g\u00f6sterir<\/code><\/pre>\n
Bu sorunu \u00e7\u00f6zmek i\u00e7in Singleton s\u0131n\u0131f\u0131nda readResolve()<\/code> metodunu uygulamak gerekir:<\/p>\n
public class SerializableSingleton implements Serializable {\n    private static SerializableSingleton instance;\n    private static final long serialVersionUID = 1L;\n\n    private SerializableSingleton() {\n        \/\/ Yap\u0131c\u0131 \u00f6zeldir\n    }\n\n    public static SerializableSingleton getInstance() {\n        if (instance == null) {\n            synchronized (SerializableSingleton.class) {\n                if (instance == null) {\n                    instance = new SerializableSingleton();\n                }\n            }\n        }\n        return instance;\n    }\n\n    \/\/ Bu metot, ters serile\u015ftirme s\u0131ras\u0131nda yeni bir nesne olu\u015fturmak yerine mevcut \u00f6rne\u011fi d\u00f6nd\u00fcr\u00fcr.\n    protected Object readResolve() {\n        return getInstance();\n    }\n\n    public void showMessage() {\n        System.out.println(\"Merhaba, ben serile\u015ftirilebilir Singleton!\");\n    }\n}<\/code><\/pre>\n
Yine, enum<\/code> Singleton bu sorunu da otomatik olarak \u00e7\u00f6zer. Enum’lar serile\u015ftirmeye kar\u015f\u0131 do\u011fal olarak diren\u00e7lidir ve ters serile\u015ftirme s\u0131ras\u0131nda her zaman ayn\u0131 enum sabitini d\u00f6nd\u00fcr\u00fcr.<\/p>\n
Uygulamalar\u0131n Kar\u015f\u0131la\u015ft\u0131r\u0131lmas\u0131<\/h3>\n
| Yakla\u015f\u0131m                       | Thread G\u00fcvenli\u011fi | Tembel Ba\u015flatma | Performans (Y\u00fcksek E\u015fzamanl\u0131l\u0131k) | Karma\u015f\u0131kl\u0131k | Yans\u0131ma G\u00fcvenli\u011fi | Serile\u015ftirme G\u00fcvenli\u011fi |
\n| :—————————– | :————— | :————– | :——————————- | :———- | :—————- | :——————— |
\n| Aceleci Ba\u015flatma               | Evet             | Hay\u0131r           | Y\u00fcksek                           | D\u00fc\u015f\u00fck       | Hay\u0131r             | Hay\u0131r (readResolve gerek) |
\n| Senkronize Metot               | Evet             | Evet            | D\u00fc\u015f\u00fck (her \u00e7a\u011fr\u0131da kilit)        | D\u00fc\u015f\u00fck       | Hay\u0131r             | Hay\u0131r (readResolve gerek) |
\n| \u00c7ift Kontroll\u00fc Kilitleme (DCL) | Evet (volatile<\/code> ile) | Evet            | Y\u00fcksek (ilk \u00e7a\u011fr\u0131 d\u0131\u015f\u0131nda)       | Orta        | Hay\u0131r             | Hay\u0131r (readResolve gerek) |
\n| \u0130stek \u00dczerine Tutucu S\u0131n\u0131f     | Evet             | Evet            | Y\u00fcksek                           | D\u00fc\u015f\u00fck-Orta  | Hay\u0131r             | Hay\u0131r (readResolve gerek) |
\n| Enum Singleton                 | Evet             | Evet (k\u0131smi)    | Y\u00fcksek                           | D\u00fc\u015f\u00fck       | Evet              | Evet                   |<\/p>\n
Sonu\u00e7<\/h3>\n
Java’da Singleton deseni uygularken thread g\u00fcvenli\u011fi, uygulaman\u0131n do\u011fru ve tutarl\u0131 \u00e7al\u0131\u015fmas\u0131 i\u00e7in hayati \u00f6neme sahiptir. Farkl\u0131 uygulama yakla\u015f\u0131mlar\u0131, thread g\u00fcvenli\u011fi, tembel ba\u015flatma ve performans aras\u0131nda farkl\u0131 denge noktalar\u0131 sunar.<\/p>\n
*   E\u011fer Singleton \u00f6rne\u011finin her zaman ihtiya\u00e7 duyulaca\u011f\u0131 kesinse ve ba\u015flatma maliyeti d\u00fc\u015f\u00fckse, Aceleci Ba\u015flatma<\/strong> en basit ve g\u00fcvenli se\u00e7enektir.
\n*   Performans\u0131n kritik oldu\u011fu ve tembel ba\u015flatman\u0131n istendi\u011fi durumlarda, \u0130stek \u00dczerine Tutucu S\u0131n\u0131f Deseni (Bill Pugh Singleton)<\/strong> genellikle en iyi ve en zarif \u00e7\u00f6z\u00fcmd\u00fcr. Java’n\u0131n s\u0131n\u0131f y\u00fckleme garantilerinden yararlanarak karma\u015f\u0131k senkronizasyon mekanizmalar\u0131na ihtiya\u00e7 duymadan thread g\u00fcvenli\u011fi ve tembel ba\u015flatma sa\u011flar.
\n*   E\u011fer en \u00fcst d\u00fczeyde g\u00fcvenlik (yans\u0131ma ve serile\u015ftirme sald\u0131r\u0131lar\u0131na kar\u015f\u0131) ve basitlik \u00f6ncelikliyse, Enum Singleton<\/strong> tart\u0131\u015fmas\u0131z en iyi se\u00e7enektir. Java 5 ve sonraki s\u00fcr\u00fcmler i\u00e7in \u00e7o\u011fu durumda tercih edilen y\u00f6ntemdir.<\/p>\n
Senkronize Metot<\/strong> yakla\u015f\u0131m\u0131 basit olsa da, gereksiz performans overhead’\u0131 nedeniyle genellikle \u00f6nerilmez. \u00c7ift Kontroll\u00fc Kilitleme (DCL)<\/strong>, volatile<\/code> anahtar kelimesiyle do\u011fru uyguland\u0131\u011f\u0131nda thread g\u00fcvenli ve verimli olsa da, karma\u015f\u0131kl\u0131\u011f\u0131 ve volatile<\/code>‘\u0131n inceliklerini anlama gereklili\u011fi nedeniyle hata yapmaya daha a\u00e7\u0131kt\u0131r.<\/p>\n
Sonu\u00e7 olarak, bir Singleton s\u0131n\u0131f\u0131 tasarlarken, uygulaman\u0131n \u00f6zel gereksinimlerini ve performans beklentilerini g\u00f6z \u00f6n\u00fcnde bulundurarak en uygun thread g\u00fcvenli uygulama yakla\u015f\u0131m\u0131n\u0131 se\u00e7mek \u00f6nemlidir. G\u00fcn\u00fcm\u00fcz Java uygulamalar\u0131nda, Enum Singleton veya \u0130stek \u00dczerine Tutucu S\u0131n\u0131f Deseni, sa\u011flam ve g\u00fcvenilir Singleton’lar olu\u015fturmak i\u00e7in en \u00e7ok \u00f6nerilen y\u00f6ntemlerdir.<\/body><\/p>\n","protected":false},"excerpt":{"rendered":"Java Singleton S\u0131n\u0131flar\u0131nda Thread G\u00fcvenli\u011fi\nGiri\u015f\nTekil Nesne (Singleton) tasar\u0131m deseni, bir s\u0131n\u0131f\u0131n yaln\u0131zca bir \u00f6rne\u011finin olu\u015fturul","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"csco_page_header_type":"","csco_page_load_nextpost":"","csco_page_subscribe_form":"","csco_page_contact_form":"","footnotes":""},"categories":[1408],"tags":[],"class_list":{"0":"post-32166","1":"post","2":"type-post","3":"status-publish","4":"format-standard","6":"category-java","7":"cs-entry","8":"cs-video-wrap"},"yoast_head":"\nJava Singleton S\u0131n\u0131flar\u0131nda Thread G\u00fcvenli\u011fi - Kodlar\u0131n Gizemli D\u00fcnyas\u0131<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/\" \/>\n<meta property=\"og:locale\" content=\"tr_TR\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Java Singleton S\u0131n\u0131flar\u0131nda Thread G\u00fcvenli\u011fi\" \/>\n<meta property=\"og:description\" content=\"Java Singleton S\u0131n\u0131flar\u0131nda Thread G\u00fcvenli\u011fi Giri\u015f Tekil Nesne (Singleton) tasar\u0131m deseni, bir s\u0131n\u0131f\u0131n yaln\u0131zca bir \u00f6rne\u011finin olu\u015fturul\" \/>\n<meta property=\"og:url\" content=\"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/\" \/>\n<meta property=\"og:site_name\" content=\"Kodlar\u0131n Gizemli D\u00fcnyas\u0131\" \/>\n<meta property=\"article:published_time\" content=\"2025-10-18T10:40:54+00:00\" \/>\n<meta name=\"author\" content=\"Fatih Soysal\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Yazan:\" \/>\n\t<meta name=\"twitter:data1\" content=\"Fatih Soysal\" \/>\n\t<meta name=\"twitter:label2\" content=\"Tahmini okuma s\u00fcresi\" \/>\n\t<meta name=\"twitter:data2\" content=\"16 dakika\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/#article\",\"isPartOf\":{\"@id\":\"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/\"},\"author\":{\"name\":\"Fatih Soysal\",\"@id\":\"https:\/\/fatihsoysal.com\/blog\/#\/schema\/person\/002a254750921dcfd568a99e48240dd1\"},\"headline\":\"Java Singleton S\u0131n\u0131flar\u0131nda Thread G\u00fcvenli\u011fi\",\"datePublished\":\"2025-10-18T10:40:54+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/\"},\"wordCount\":2515,\"commentCount\":0,\"publisher\":{\"@id\":\"https:\/\/fatihsoysal.com\/blog\/#\/schema\/person\/002a254750921dcfd568a99e48240dd1\"},\"articleSection\":[\"Java\"],\"inLanguage\":\"tr\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/#respond\"]}],\"copyrightYear\":\"2025\",\"copyrightHolder\":{\"@id\":\"https:\/\/fatihsoysal.com\/blog\/#organization\"}},{\"@type\":\"WebPage\",\"@id\":\"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/\",\"url\":\"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/\",\"name\":\"Java Singleton S\u0131n\u0131flar\u0131nda Thread G\u00fcvenli\u011fi - Kodlar\u0131n Gizemli D\u00fcnyas\u0131\",\"isPartOf\":{\"@id\":\"https:\/\/fatihsoysal.com\/blog\/#website\"},\"datePublished\":\"2025-10-18T10:40:54+00:00\",\"breadcrumb\":{\"@id\":\"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/#breadcrumb\"},\"inLanguage\":\"tr\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Anasayfa\",\"item\":\"https:\/\/fatihsoysal.com\/blog\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Java Singleton S\u0131n\u0131flar\u0131nda Thread G\u00fcvenli\u011fi\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/fatihsoysal.com\/blog\/#website\",\"url\":\"https:\/\/fatihsoysal.com\/blog\/\",\"name\":\"Fatihsoysal.com\",\"description\":\"Blog - Yaz\u0131l\u0131m D\u00fcnyas\u0131 Tecr\u00fcbelerim\",\"publisher\":{\"@id\":\"https:\/\/fatihsoysal.com\/blog\/#\/schema\/person\/002a254750921dcfd568a99e48240dd1\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/fatihsoysal.com\/blog\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"tr\"},{\"@type\":[\"Person\",\"Organization\"],\"@id\":\"https:\/\/fatihsoysal.com\/blog\/#\/schema\/person\/002a254750921dcfd568a99e48240dd1\",\"name\":\"Fatih Soysal\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"tr\",\"@id\":\"https:\/\/fatihsoysal.com\/blog\/#\/schema\/person\/image\/\",\"url\":\"https:\/\/fatihsoysal.com\/blog\/wp-content\/uploads\/2024\/04\/cropped-replicate-prediction-3kgg1hgjn5rgp0cf0p5tr0jw7w-1.png\",\"contentUrl\":\"https:\/\/fatihsoysal.com\/blog\/wp-content\/uploads\/2024\/04\/cropped-replicate-prediction-3kgg1hgjn5rgp0cf0p5tr0jw7w-1.png\",\"width\":512,\"height\":512,\"caption\":\"Fatih Soysal\"},\"logo\":{\"@id\":\"https:\/\/fatihsoysal.com\/blog\/#\/schema\/person\/image\/\"},\"description\":\"Kullan\u0131m ve kodlama m\u00fckemmeliyetini odak alan uygulamalar olu\u015fturma deneyimine sahip, profesyonel olarak 15+ y\u0131l \u00fczeri deneyime sahip bir yaz\u0131l\u0131m m\u00fchendisi.\",\"url\":\"https:\/\/fatihsoysal.com\/blog\/author\/fatihsoysal\/\"}]}<\/script>\n<!-- \/ Yoast SEO Premium plugin. -->","yoast_head_json":{"title":"Java Singleton S\u0131n\u0131flar\u0131nda Thread G\u00fcvenli\u011fi - Kodlar\u0131n Gizemli D\u00fcnyas\u0131","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/","og_locale":"tr_TR","og_type":"article","og_title":"Java Singleton S\u0131n\u0131flar\u0131nda Thread G\u00fcvenli\u011fi","og_description":"Java Singleton S\u0131n\u0131flar\u0131nda Thread G\u00fcvenli\u011fi Giri\u015f Tekil Nesne (Singleton) tasar\u0131m deseni, bir s\u0131n\u0131f\u0131n yaln\u0131zca bir \u00f6rne\u011finin olu\u015fturul","og_url":"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/","og_site_name":"Kodlar\u0131n Gizemli D\u00fcnyas\u0131","article_published_time":"2025-10-18T10:40:54+00:00","author":"Fatih Soysal","twitter_card":"summary_large_image","twitter_misc":{"Yazan:":"Fatih Soysal","Tahmini okuma s\u00fcresi":"16 dakika"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/#article","isPartOf":{"@id":"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/"},"author":{"name":"Fatih Soysal","@id":"https:\/\/fatihsoysal.com\/blog\/#\/schema\/person\/002a254750921dcfd568a99e48240dd1"},"headline":"Java Singleton S\u0131n\u0131flar\u0131nda Thread G\u00fcvenli\u011fi","datePublished":"2025-10-18T10:40:54+00:00","mainEntityOfPage":{"@id":"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/"},"wordCount":2515,"commentCount":0,"publisher":{"@id":"https:\/\/fatihsoysal.com\/blog\/#\/schema\/person\/002a254750921dcfd568a99e48240dd1"},"articleSection":["Java"],"inLanguage":"tr","potentialAction":[{"@type":"CommentAction","name":"Comment","target":["https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/#respond"]}],"copyrightYear":"2025","copyrightHolder":{"@id":"https:\/\/fatihsoysal.com\/blog\/#organization"}},{"@type":"WebPage","@id":"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/","url":"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/","name":"Java Singleton S\u0131n\u0131flar\u0131nda Thread G\u00fcvenli\u011fi - Kodlar\u0131n Gizemli D\u00fcnyas\u0131","isPartOf":{"@id":"https:\/\/fatihsoysal.com\/blog\/#website"},"datePublished":"2025-10-18T10:40:54+00:00","breadcrumb":{"@id":"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/#breadcrumb"},"inLanguage":"tr","potentialAction":[{"@type":"ReadAction","target":["https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/fatihsoysal.com\/blog\/java-singleton-siniflarinda-thread-guvenligi\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Anasayfa","item":"https:\/\/fatihsoysal.com\/blog\/"},{"@type":"ListItem","position":2,"name":"Java Singleton S\u0131n\u0131flar\u0131nda Thread G\u00fcvenli\u011fi"}]},{"@type":"WebSite","@id":"https:\/\/fatihsoysal.com\/blog\/#website","url":"https:\/\/fatihsoysal.com\/blog\/","name":"Fatihsoysal.com","description":"Blog - Yaz\u0131l\u0131m D\u00fcnyas\u0131 Tecr\u00fcbelerim","publisher":{"@id":"https:\/\/fatihsoysal.com\/blog\/#\/schema\/person\/002a254750921dcfd568a99e48240dd1"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/fatihsoysal.com\/blog\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"tr"},{"@type":["Person","Organization"],"@id":"https:\/\/fatihsoysal.com\/blog\/#\/schema\/person\/002a254750921dcfd568a99e48240dd1","name":"Fatih Soysal","image":{"@type":"ImageObject","inLanguage":"tr","@id":"https:\/\/fatihsoysal.com\/blog\/#\/schema\/person\/image\/","url":"https:\/\/fatihsoysal.com\/blog\/wp-content\/uploads\/2024\/04\/cropped-replicate-prediction-3kgg1hgjn5rgp0cf0p5tr0jw7w-1.png","contentUrl":"https:\/\/fatihsoysal.com\/blog\/wp-content\/uploads\/2024\/04\/cropped-replicate-prediction-3kgg1hgjn5rgp0cf0p5tr0jw7w-1.png","width":512,"height":512,"caption":"Fatih Soysal"},"logo":{"@id":"https:\/\/fatihsoysal.com\/blog\/#\/schema\/person\/image\/"},"description":"Kullan\u0131m ve kodlama m\u00fckemmeliyetini odak alan uygulamalar olu\u015fturma deneyimine sahip, profesyonel olarak 15+ y\u0131l \u00fczeri deneyime sahip bir yaz\u0131l\u0131m m\u00fchendisi.","url":"https:\/\/fatihsoysal.com\/blog\/author\/fatihsoysal\/"}]}},"yoast_meta":{"yoast_wpseo_title":"","yoast_wpseo_metadesc":"","yoast_wpseo_canonical":""},"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/fatihsoysal.com\/blog\/wp-json\/wp\/v2\/posts\/32166","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fatihsoysal.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fatihsoysal.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fatihsoysal.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fatihsoysal.com\/blog\/wp-json\/wp\/v2\/comments?post=32166"}],"version-history":[{"count":1,"href":"https:\/\/fatihsoysal.com\/blog\/wp-json\/wp\/v2\/posts\/32166\/revisions"}],"predecessor-version":[{"id":32167,"href":"https:\/\/fatihsoysal.com\/blog\/wp-json\/wp\/v2\/posts\/32166\/revisions\/32167"}],"wp:attachment":[{"href":"https:\/\/fatihsoysal.com\/blog\/wp-json\/wp\/v2\/media?parent=32166"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fatihsoysal.com\/blog\/wp-json\/wp\/v2\/categories?post=32166"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fatihsoysal.com\/blog\/wp-json\/wp\/v2\/tags?post=32166"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}