java.util.TreeSet.pollFirst() 方法示例


java.util.TreeSet.pollFirst() 方法示例

package com.codingdict;

import java.util.Iterator;
import java.util.TreeSet;

public class TreeSetDemo {
   public static void main(String[] args) {

      // creating a TreeSet
      TreeSet <Integer>treeadd = new TreeSet<Integer>();

      // adding in the tree set
      treeadd.add(1);
      treeadd.add(13);
      treeadd.add(17);
      treeadd.add(2);

      // retrieve and remove the first element
      System.out.println("First element is: "+treeadd.pollFirst());

      // create iterator
      Iterator iterator;
      iterator = treeadd.iterator();

      // displaying the Tree set data
      System.out.println("Tree set data after removing: ");     

      while (iterator.hasNext()) {
         System.out.println(iterator.next() + " ");
      }
   }     
}