How to Find the Position of an Element in a Java Array?

Retrieving Element Position in Java Arrays

Within Java's Arrays class, there is no direct "indexOf" method to determine the position of a specific element within an array. However, the Arrays utility class offers alternative methods to achieve this functionality.

Unsorted Arrays (Non-Primitives)

For unsorted arrays that contain object references, you can utilize the following code:

java.util.Arrays.asList(theArray).indexOf(o);

This approach leverages Java's reflection API to convert the array into a list, allowing you to use the indexOf method.

Unsorted Arrays (Primitives)

If your array contains primitive data types and is unsorted, you can employ solutions such as:

• [Kerem Baydoğan's Method](link to Kerem's solution)
• [Andrew McKinlay's Method](link to Andrew's solution)
• [Mishax's Method](link to Mishax's solution)

Sorted Arrays

For sorted arrays, regardless of whether they contain primitives or object references, you can leverage Java's binary search algorithm for enhanced performance:

java.util.Arrays.binarySearch(theArray, o);

This method returns the index of the element if found, or a negative value indicating the insertion point where the element should be placed.

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