Java中的数组列表lastIndexOf()，示例

lastIndexOf(element)


// Java code to demonstrate the working of
// lastIndexOf() method in ArrayList
// for ArrayList functions
import java.util.ArrayList;
public class GFG {
    public static void main(String[] args)
    {
        // creating an Empty Integer ArrayList
        ArrayList<Integer> arr = new ArrayList<Integer>(7);
        // using add() to initialize values
        arr.add(10);
        arr.add(20);
        arr.add(30);
        arr.add(40);
        arr.add(30);
        arr.add(30);
        arr.add(40);
        System.out.println("The list initially " + arr);
        // last index of 30
        int element = arr.lastIndexOf(30);
        if (element != -1)
            System.out.println("the lastIndexof of" + 
                             " 30 is " + element);
        else
            System.out.println("30 is not present in" + 
                                        " the list");
        // last index of 100
        element = arr.lastIndexOf(100);
        if (element != -1)
            System.out.println("the lastIndexof of 100" + 
                                      " is " + element);
        else
            System.out.println("100 is not present in" + 
                                           " the list");
    }
}


The list initially [10, 20, 30, 40, 30, 30, 40]
the lastIndexof of 30 is 5
100 is not present in the list