Can I iterate through enum java?
Enums do not have methods for iteration like forEach() or iterator(). Instead, we can use the array of the Enum values returned by the values() method.
How do you iterate through an Enumeration?
To iterate through an enumeration, you can move it into an array using the GetValues method. You could also iterate through an enumeration using a For… Each statement, using the GetNames or GetValues method to extract the string or numeric value.
What is difference between iteration and Enumeration?
Iterator can do modifications (e.g using remove() method it removes the element from the Collection during traversal). Enumeration interface acts as a read only interface, one can not do any modifications to Collection while traversing the elements of the Collection.
Is Enumeration fail-fast?
Fail-fast or Fail-safe : Enumeration is fail-safe in nature. It does not throw ConcurrentModificationException if Collection is modified during the traversal. Iterator is fail-fast in nature. It throws ConcurrentModificationException if a Collection is modified while iterating other than its own remove() method.
How do you create an enumeration object in Java?
Example 2
- import java.util.*;
- public class CollectionsEnumerationExample2 {
- public static void main(String[] args) {
- //Create array list object.
- List Enum = new ArrayList();
- Enum.add(1100);
- Enum.add(2100);
- Enum.add(5100);
What is Enumeration interface in Java?
Advertisements. The Enumeration interface defines the methods by which you can enumerate (obtain one at a time) the elements in a collection of objects. This legacy interface has been superceded by Iterator. Although not deprecated, Enumeration is considered obsolete for new code.
What is Enumeration in Java?
Java Enums can be thought of as classes which have a fixed set of constants (a variable that does not change). The Java enum constants are static and final implicitly. It is available since JDK 1.5. Enums are used to create our own data type like classes.
Is Hashtable throw ConcurrentModificationException?
Iterator in the Hashtable is fail-safe because enumerator for the Hashtable is not throw ConcurrentModificationException if any other Thread modifies the map structurally by adding or removing any element except Iterator’s own remove() method.
What is the use of enum?
Enums are used when we know all possible values at compile-time, such as choices on a menu, rounding modes, command-line flags, etc. It is not necessary that the set of constants in an enum type stay fixed for all time. In Java (from 1.5), enums are represented using enum data type.
Is enum a type?
An enum type is a special data type that enables for a variable to be a set of predefined constants. The variable must be equal to one of the values that have been predefined for it. Common examples include compass directions (values of NORTH, SOUTH, EAST, and WEST) and the days of the week.