Java Guava | Doubles.lastIndexOf() method with Examples

Last Updated : 31 Jan, 2019

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 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 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://google.github.io/guava/releases/19.0/api/docs/com/google/common/primitives/Doubles.html#lastIndexOf(double[], %20double)

Attention reader! Don’t stop learning now. Get hold of all the important Java Foundation and Collections concepts with the Fundamentals of Java and Java Collections Course at a student-friendly price and become industry ready. To complete your preparation from learning a language to DS Algo and many more, please refer Complete Interview Preparation Course.

My Personal Notes

Related Articles

Java Guava | Doubles.lastIndexOf() method with Examples