Use add() from ArrayList to push_back.

For pop_back you have to play around a bit more with indexes and remove().

Let's look at this example:

// push_back equivalent
ArrayList<int> a = new ArrayList<int>();
a.add(2);             // Add element to the ArrayList.
a.add(4);

// pop_back equivalent.
a.remove(a.size()-1); // Remove the last element from the ArrayList.

Use ArrayList for dynamically add and remove element.

For push_back() use .add()

add() method to add elements in the list

List<Integer> arrlist = new ArrayList<Integer>(); 
arrlist.add(10); 

For pop_back() use .remove()

remove() used for removing the element at the specified position in this list. So, pass last index in method to delete last element

arrlist.remove(arrlist.size() - 1); 

You can use add() for push_back() and remove() for pop_back().

ArrayList<data_type> data = new ArrayList<data_type>();
data.add(value1);
data.add(value2);
data.remove(data.size() - 1);

P.S : arraylist is a container not API.

We can use the LinkedList<E> data structure

Adding at the end by: add(E e)

removing at the end by using: pollLast()

Example:

package test;

import java.util.*;  
public class test{  
public static void main(String args[]){  

    LinkedList<String> al=new LinkedList<String>();  
    al.add("element1");  
    al.add("element2");  
    al.add("element3");  

    Iterator<String> itr=al.iterator();  
    while(itr.hasNext()){  
        System.out.print(itr.next()+" ");  
    } 

    System.out.println(" ");

    al.add("element4");  

    itr=al.iterator();  
    while(itr.hasNext()){  
        System.out.print(itr.next()+ " "); 
    } 
    System.out.println(" ");

    //pop_back
    al.pollLast();

    itr=al.iterator();  
    while(itr.hasNext()){  
        System.out.print(itr.next()+" ");  
      }  
    }  
}  

result:

element1 element2 element3  
element1 element2 element3 element4  
element1 element2 element3