Java Iterator vs. Iterable: A step into writing elegant code
Feb 19, 2024 pm 02:54 PM
Java Iterator and Iterable are very important concepts in Java programming. They can help developers write code more elegantly. In actual development, mastering the use of these two interfaces can make the code more concise and efficient. This article will introduce the functions and usage of Java Iterator and Iterable in detail to help readers better understand and use these two interfaces and make the code more elegant. Let’s get into writing elegant code together!
TheIterator interface is an interface used to traverse a collection. It provides several methods, including hasNext(), next(), and remove(). The hasNext() method returns a Boolean value indicating whether there is a next element in the collection. The next() method returns the next element in the collection and removes it from the collection. The remove() method removes the current element from the collection.
The following code example demonstrates how to use the Iterator interface to traverse a collection:
List<String> names = Arrays.asList("John", "Mary", "Bob");
Iterator<String> iterator = names.iterator();
while (iterator.hasNext()) {
String name = iterator.next();
System.out.println(name);
}
Iterable interface
The Iterable interface is another interface for traversing collections. It provides one method, the iterator() method. The iterator() method returns an Iterator object that can be used to iterate over the collection.
The following code example demonstrates how to use the Iterable interface to traverse a collection:
List<String> names = Arrays.asList("John", "Mary", "Bob");
for (String name : names) {
System.out.println(name);
}
The difference between Iterator and Iterable
Iterator and Iterable are two very similar interfaces, both used to traverse collections. However, there are some differences between them.
- Iterator is an object that traverses a collection, and Iterable is a collection that can be traversed.
- Iterator provides hasNext(), next() and remove() methods, while Iterable only provides iterator() method.
- Iterator can move back and forth in the collection, while Iterable can only traverse the collection from beginning to end.
When to use Iterator and Iterable
Both Iterator and Iterable can be used in Java to traverse collections. However, there are some situations where using Iterator is more appropriate, and other situations where using Iterable is more appropriate.
- If you need to move back and forth in a collection, then you should use an Iterator.
- If you need to traverse the collection from beginning to end, then you should use Iterable.
in conclusion
Iterator and Iterable are two important programming interfaces that can help you write more elegant and reusable code. By understanding the usage of these two interfaces, you will be able to write better Java code.
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