您可以使用此代码

private List myList = new ArrayList();
private void addItemToList(Object obj){
    if(myList.size()<10){
      myList.add(0,obj);
    }else{
      myList.add(0,obj);
      myList.remove(10);
    }
}

您可以使用此代码

private List myList = new ArrayList();
private void addItemToList(Object obj){
    if(myList.size()<10){
      myList.add(0,obj);
    }else{
      myList.add(0,obj);
      myList.remove(10);
    }
}

import java.util.*:
public class Logic {
  List<String> list = new ArrayList<String>();
  public static void main(String...args) {
  Scanner input = new Scanner(System.in);
    Logic obj = new Logic();
      for (int i=0;i<=20;i++) {
        String string = input.nextLine();
        obj.myLogic(string);
        obj.printList();
      }
 }
 public void myLogic(String strObj) {
   if (this.list.size()>=10) {
      this.list.remove(this.list.size()-1);
   } else {
     list.add(strObj); 
   }
 }
 public void printList() {
 System.out.print(this.list);
 }
}

您可以使用列表方法，删除和添加

list.add(lowestIndex, element);
list.remove(highestIndex, element);

Java LinkedList提供了addFirst(E E)和push(E E)方法，用于将元素添加到列表前面。

https://docs.oracle.com/javase/7/docs/api/java/util/LinkedList.html addFirst (E)

import com.google.common.collect.Lists;

import java.util.List;

/**
 * @author Ciccotta Andrea on 06/11/2020.
 */
public class CollectionUtils {

    /**
     * It models the prepend O(1), used against the common append/add O(n)
     * @param head first element of the list
     * @param body rest of the elements of the list
     * @return new list (with different memory-reference) made by [head, ...body]
     */
    public static <E> List<Object> prepend(final E head, List<E> final body){
        return Lists.asList(head, body.toArray());
    }

    /**
     * it models the typed version of prepend(E head, List<E> body)
     * @param type the array into which the elements of this list are to be stored
     */
    public static <E> List<E> prepend(final E head, List<E> body, final E[] type){
        return Lists.asList(head, body.toArray(type));
    }
}