Java Guava | Doubles.lastIndexOf() method with Examples

The lastIndexOf() method of Doubles Class in Guava library is used to find the last index of the given double value in a double array. This double value to be searched and the double array in which it is to be searched, both are passed as a parameter to this method. It returns an integer value which is the last index of the specified double value. If the value is not found, it returns -1. Syntax:

public static int lastIndexOf(double[] array,
                              double target)

Parameters: This method accepts two mandatory parameters:

array: which is the array of double values in which the double value is to searched.
target: which is double value to be searched for last index in the double array.

Return Value: This method returns an integer value which is the last index of the specified double value. If the value is not found, it returns -1. Below programs illustrates this method: Example 1:

Java

// Java code to show implementation of
// Guava's Doubles.lastIndexOf() method

import com.google.common.primitives.Doubles;
import java.util.Arrays;

class GFG {

    // Driver's code
    public static void main(String[] args)
    {

        // Creating a double array
        double[] arr = { 1.2, 2.2, 3.2, 4.2,
                         3.2, 5.6, 3.2, 4.4 };

        double target = 3.2;

        // Using Doubles.lastIndexOf() method
        // to get the index of last appearance
        // of a given element in array
        // and return -1 if element is
        // not found in the array
        int index
            = Doubles.lastIndexOf(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 6

Example 2:

Java

// Java code to show implementation of
// Guava's Doubles.lastIndexOf() method

import com.google.common.primitives.Doubles;
import java.util.Arrays;

class GFG {

    // Driver's code
    public static void main(String[] args)
    {
        // Creating a double array
        double[] arr = { 1.2, 2.2, 3.2, 4.2,
                         3.2, 5.6, 3.2, 4.4 };

        double target = 10.2;

        // Using Doubles.lastIndexOf() method
        // to get the index of last appearance
        // of a given element in array
        // and return -1 if element is
        // not found in the array
        int index
            = Doubles.lastIndexOf(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/19.0/api/docs/com/google/common/primitives/Doubles.html#lastIndexOf(double%5B%5D, %20double)

Java Guava | Doubles.lastIndexOf() method with Examples

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