Menene nau'i-nau'i na primitive vs nau'i-nau'i na reference a Java?

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Java yana da nau'i-nau'i masu mahimmanci biyu: **primitives** (sauran ƙimamorin sakandare ake ajiyar jiya-jiya) da **nau'i-nau'i na reference** (abubuwa, inda mai ƙiginta ke ajiye tunani/pointer zuwa object). Suna da halaye waɗa-waɗa a alaƙa, wasikar, da bambantawa. ## Nau'i-nau'i na primitive 8 ```java int i = 42; // 32-bit integer long l = 100L; // 64-bit integer double d = 3.14; // 64-bit floating point float f = 1.5f; // 32-bit floating point boolean b = true; // true/false char c = 'A'; // 16-bit Unicode character byte by = 127; // 8-bit short s = 1000; // 16-bit ``` Primitives suna ajiye **ainihin ƙimar** jiya-jiya, suna da ƙayyadaddun girma, ba za su iya zama null ba, kuma suna zaune akan tuddi (ga locals). Suna da sauri da inganta alaƙa. ## Nau'i-nau'i na reference — abubuwa ```java String name = "Ann"; // reference to a String object int[] arr = {1, 2, 3}; // reference to an array object List list = new ArrayList<>(); // reference to a List object Person p = new Person("Bob"); // reference to a Person object ``` Maimaitawa na reference suna ajiye **reference** (tunaninsa alaƙa) zuwa object da aka ajiye akan falle — ba object da kansa ba. Za su iya zama `null`. ## Bambanta mahimmanci: wasikar da bambantawa ```java // primitives — assignment COPIES the value (independent) int a = 5; int b = a; // b is a COPY b = 10; // a is still 5 // references — assignment COPIES the reference (both point to the SAME object) int[] x = {1, 2, 3}; int[] y = x; // y points to the SAME array y[0] = 99; // x[0] is now 99 too! (shared object) ``` ```java // == compares VALUES for primitives, but REFERENCES (identity) for objects String s1 = new String("hi"); String s2 = new String("hi"); s1 == s2; // false — different objects (different references) s1.equals(s2); // true — equals() compares CONTENT ``` Dan hankali mafi yawa ne: **`==` akan abubuwa yana bambantawa asali (wuri ɗaya?), ba abin da ke ciki ba** — yi amfani da `.equals()` don bambantawar abin da ke ciki. ## Ajiyar aji juna dua maye ```java Integer boxed = 42; // Integer is the OBJECT wrapper for int (autoboxing) int unboxed = boxed; // auto-unboxing back to primitive List nums; // collections need objects, not primitives ``` Kowane primitive yana da aji mai rikitarwa (`int`→`Integer`, jne.) don su iya koma gida inda ake buƙata abubuwa (ajiya, generics). ## Me yake da muhimmanci Bambanta na primitive-vs-reference adalah mahimmanci a Java da tushe da wawaye tsofaffin rashin dabaru da yaduwar: wasikar naka ƙimamorin primitive amma suna ba da reference ga abubuwa (don haka in ka gyara wani abu da aka ba), da ƙarafi wawa cewa **`==` yana bambantawa asali ga abubuwa** (babbar muguwar abu — yi amfani da `.equals()` don abin da ke ciki). Tunani na yau yana tasiri hujja na bambantawa, jiyya na hanya (abubuwa ana wuce ta ƙimar reference), mallaka-null (reference kuwa na iya zama null), da aiki (primitives na karfe). Abin ilimi ne mahimmanci don rubuta Java madaidaiciya.