在本教程中,我们分享了对ArrayList<String>和ArrayList<Integer>进行排序的示例。
示例 1:ArrayList<String>的排序
这里我们正在对String类型的ArrayList进行排序。我们只需调用Collections.sort(arraylist)方法即可。输出列表将按字母顺序排序。
import java.util.*;public class Details { public static void main(String args[]){ ArrayList<String> listofcountries = new ArrayList<String>(); listofcountries.add("India"); listofcountries.add("US"); listofcountries.add("China"); listofcountries.add("Denmark"); /*Unsorted List*/ System.out.println("Before Sorting:"); for(String counter: listofcountries){ System.out.println(counter); } /* Sort statement*/ Collections.sort(listofcountries); /* Sorted List*/ System.out.println("After Sorting:"); for(String counter: listofcountries){ System.out.println(counter); } }}
输出:
Before Sorting:IndiaUSChinaDenmarkAfter Sorting:ChinaDenmarkIndiaUS
示例 2:ArrayList<Integer>的排序
相同的Collections.sort()方法也可用于对整数ArrayList进行排序。
import java.util.*;public class ArrayListOfInteger { public static void main(String args[]){ ArrayList<Integer> arraylist = new ArrayList<Integer>(); arraylist.add(11); arraylist.add(2); arraylist.add(7); arraylist.add(3); /* ArrayList before the sorting*/ System.out.println("Before Sorting:"); for(int counter: arraylist){ System.out.println(counter); } /* Sorting of arraylist using Collections.sort*/ Collections.sort(arraylist); /* ArrayList after sorting*/ System.out.println("After Sorting:"); for(int counter: arraylist){ System.out.println(counter); } }}
输出:
Before Sorting:11273After Sorting:23711
