Ints indexOf() function | Guava | Java Last Updated : 11 Jul, 2025 Comments Improve Suggest changes Like Article Like Report Guava's Ints.indexOf(int[] array, int target) method returns the index of the first appearance of the value target in array. Syntax: public static int indexOf(int[] array, int target) Parameters: This method accepts the following parameters: array: An array of int values, possibly empty. target: A primitive int value. Return Value: This method returns the least index i for which array[i] == target, or -1 if no such index exists. Example 1: Java // Java code to show implementation of // Guava's Ints.indexOf() method import com.google.common.primitives.Ints; import java.util.Arrays; class GFG { // Driver's code public static void main(String[] args) { // Creating an integer array int[] arr = { 1, 2, 3, 4, 3, 5 }; int target = 3; // Using Ints.indexOf(int[] array, int target) // method to get the index of first appearance // of a given element in array and return -1 // if element is not found in the array int index = Ints.indexOf(arr, target); if (index != -1) { System.out.println("Target is present at index " + index); } else { System.out.println("Target is not present" + " in the array"); } } } Output: Target is present at index 2 Example 2: Java // Java code to show implementation of // Guava's Ints.indexOf() method import com.google.common.primitives.Ints; import java.util.Arrays; class GFG { // Driver's code public static void main(String[] args) { // Creating an integer array int[] arr = { 3, 5, 7, 11, 13 }; int target = 17; // Using Ints.indexOf(int[] array, int target) method // to get the index of first appearance of a // given element in array and return -1 if // element is not found in the array int index = Ints.indexOf(arr, target); if (index != -1) { System.out.println("Target is present at index " + index); } else { System.out.println("Target is not present" + " in the array"); } } } Output: Target is not present in the array Reference: https://guava.dev/releases/22.0/api/docs/com/google/common/primitives/Ints.html#indexOf-int:A-int- Comment More infoAdvertise with us Next Article Introduction to Java S Sahil_Bansall Follow Improve Article Tags : Java java-guava Practice Tags : Java Similar Reads Java Tutorial Java is a high-level, object-oriented programming language used to build web apps, mobile applications, and enterprise software systems. 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