Configurations

Arrays can be configured through

  • .add()</li>
  • .get()</li>
  • .set ()</li>
  • .sort()</li>
  • .clear()
    • </ul>

    The .add method adds an index to the array list and the .get calls the specific index number. The .set method sets the index to a new index. The .sort method sorts the indexes in a certain order and .clear will clear all the indexes in the array.

    </div> </div> </div> 
    import java.util.ArrayList;
import java.util.Collections;

public class Main {
    public static void main() {
        ArrayList<String> sports = new ArrayList<String>(); //Creates a new array
        sports.add("Football");
        sports.add("Basketball"); //adds different sports to the array
        sports.add("Soccer");
        sports.add("Baseball");
        sports.add("Tennis");
        System.out.println(sports); // prints the array

        System.out.println(" ");

        for (int i = 0; i < 5; i++) {
            System.out.println(sports.get(i)); // prints each array separately
        }

        System.out.println(" ");
        System.out.println("The size of the array is " + sports.size()); //prints the size of the array

        sports.set(3, "Golf"); // changes the 3 array to "Golf"
        System.out.println("The 3 array has been changed to " + sports.get(3));

        System.out.println(" ");

        Collections.sort(sports); //sorts the array in alphabetical order
        System.out.println("The array list is in alphabetical order:");
        for (String i : sports) {
            System.out.println(i);
        }

        System.out.println(" ");
        sports.clear(); //clears the array
        System.out.println("The array list is now empty and says:" + sports);
    }
}

Main.main();

    [Football, Basketball, Soccer, Baseball, Tennis]
 
Football
Basketball
Soccer
Baseball
Tennis
 
The size of the array is 5
The 3 array has been changed to Golf
 
The array list is in alphabetical order:
Basketball
Football
Golf
Soccer
Tennis
 
The array list is now empty and says:[]

    Searching

    • Searching is the location of data in a linear structure
    • involves control structures
    • if match then index is printed
    int sum = 0;
for (String name: roster) {
    sum = sum + name.length();
}
System.out.println(sum);

    Sorting

    • Sorting happens by putting the ArrayList in a certain order
    • Collections.sort({list name}) will ascend order
    • Collections.sort(ArrayList, Collections.reverseOrder()) will descend order

    Homework

    https://jz21324.github.io/Vcode/jupyter/2022/12/03/array-list-hw.html

    </div>