Search an element of ArrayList with indexOf and lastIndexOf : ArrayList « Collections « Java Tutorial






import java.util.ArrayList;

public class Main {
  public static void main(String[] args) {
    ArrayList<String> arrayList = new ArrayList<String>();

    arrayList.add("2");
    arrayList.add("2");
    arrayList.add("3");
    arrayList.add("4");
    arrayList.add("5");
    arrayList.add("1");
    arrayList.add("2");

    System.out.println(arrayList.contains("2"));

    int index = arrayList.indexOf("4");
    if (index == -1)
      System.out.println("not contain 4");
    else
      System.out.println("4 at index :" + index);

    int lastIndex = arrayList.lastIndexOf("1");
    if (lastIndex == -1)
      System.out.println("not contain 1");
    else
      System.out.println("Last index :"+ lastIndex);
  }
}
/*true
4 at index :3
Last index :5
*/








9.11.ArrayList
9.11.1.ArrayList Class
9.11.2.Creating an ArrayList
9.11.3.A boolean is being stored and then retrieved from an ArrayList
9.11.4.The final constructor is the copy constructor: creating a new ArrayList from another collection
9.11.5.Adding Single Elements
9.11.6.Adding elements in the middle of a List
9.11.7.Add an element to specified index of ArrayList
9.11.8.Append all elements of other Collection to ArrayList
9.11.9.Insert all elements of other Collection to Specified Index of ArrayList
9.11.10.To create a read-only list, use the unmodifiableList() method of the Collections class
9.11.11.Adding Another Collection
9.11.12.Getting an Element
9.11.13.Get Sub List of ArrayList
9.11.14.Removing a Single Element
9.11.15.Removing Another Collection(Removing elements): public boolean removeAll(Collection c)
9.11.16.Retaining Another Collection: public boolean retainAll(Collection c)
9.11.17.Removing Ranges
9.11.18.Fetching Elements with iterator
9.11.19.Checking for Existence: public boolean contains(Object element)
9.11.20.Checking for Position
9.11.21.Checking for List Containment: public boolean containsAll(Collection c)
9.11.22.Replacing Elements with the set() method: public Object set(int index, Object element)
9.11.23.Checking Size: public int size(), public boolean isEmpty()
9.11.24.Checking Capacity
9.11.25.After adding all of the elements, call the trimToSize() method
9.11.26.Copying and Cloning Lists: public Object clone()
9.11.27.ArrayList implements the empty Serializable interface
9.11.28.Checking for Equality
9.11.29.Copying elements out of a list into an array
9.11.30.Convert a List (ArrayList) to an Array with zero length array
9.11.31.Convert a List (ArrayList) to an Array with full length array
9.11.32.Copy all elements of ArrayList to an Object Array
9.11.33.Remove duplicate items from an ArrayList
9.11.34.Removing All Elements
9.11.35.Looping through a Collection object: while loop, iterator, and for each
9.11.36.If an ArrayList contains a given item
9.11.37.Search an element of ArrayList with indexOf and lastIndexOf
9.11.38.Get container with Iterator from ArrayList