What is the Iterable interface in Java and what are its advantages and disadvantages?

The Iterable<T> interface in Java represents a collection of objects that can be iterated over using a for-each loop. It defines a single method iterator(), which returns an Iterator<T> object that allows sequential access to the elements of the collection.

Advantages:

• Allows the use of convenient for-each syntax for traversing elements.
• Universal: many collections and data structures implement Iterable, ensuring compatibility.
• Provides an abstraction of iteration, hiding implementation details.

Disadvantages:

• Does not support random access to elements (e.g., by index).
• The iterator may be single-use; after a full traversal, it cannot be reused without creating a new one.
• Does not guarantee thread safety if the collection is modified during iteration.

Example of usage:

List<String> list = Arrays.asList("a", "b", "c");
for (String s : list) {
    System.out.println(s);
}