RKTechGame | Java Iterators & Enhanced For Loop

Iterator Interface Kya Hai?

Iterator interface Java Collections Framework me elements ko sequentially traverse karne ka tarika provide karta hai. Matlab ke aap collection ke items ko ek ek kar ke access kar sakte hain bina collection ke andar ki implementation jaane.

Mukhya methods:

• hasNext(): Check karta hai ki koi agla element available hai ya nahi.
• next(): Agla element return karta hai.
• remove(): Jo element last return hua hai use collection se hata deta hai (optional method).

Example (ArrayList ke saath):

ArrayList<String> list = new ArrayList<>();
list.add("Java");
list.add("Python");
list.add("C++");

Iterator<String> it = list.iterator();
while (it.hasNext()) {
  System.out.println(it.next());
}

Enhanced For Loop (For-Each Loop) Kya Hai?

Java 5 me introduce hua, Enhanced For Loop iterating ko asaan aur readable banata hai, especially jab aapko sirf elements ko access karna ho bina collection ko modify kiye.

Syntax:

for (ElementType element : collection) {
    // Yahan element ko use karo
}

Example:

ArrayList<String> list = new ArrayList<>();
list.add("Java");
list.add("Python");
list.add("C++");

for (String lang : list) {
  System.out.println(lang);
}

Yeh syntax cleaner hai aur iterator ko internally use karta hai. Lekin agar aapko iteration ke dauran elements ko remove karna hai toh iterator use karna better hai.