一、Collections.sort()从小到大排序:Collections.sort(list);
List<Integer> list = new ArrayList<Integer>();List.add(1);list.add(5);list.add(10);list.add(2);list.add(11);list.add(55);list.add(8);System.out.println("原始list为:");for(int i = 0;i<list.size();i++){System.out.print(list.get(i)+" ");}Collections.sort(list);//从小到大进行排序System.out.println("\nCollections.sort从小到大排序以后的list为:");for(int i = 0;i<list.size();i++){System.out.print(list.get(i)+" ");}
二、Collections.sort()从大到小排序:
Collections.sort(list,new Comparator<Integer>() {
@Override public int compare(Integer o1, Integer o2) { // TODO Auto-generated method stub return o2-o1; } });
List<Integer> list = new ArrayList<Integer>();list.add(1);list.add(5);list.add(10);list.add(2);list.add(11);list.add(55);list.add(8);System.out.println("原始list为:");for(int i = 0;i<list.size();i++){System.out.print(list.get(i)+" ");}Collections.sort(list,new Comparator<Integer>() {@Overridepublic int compare(Integer o1, Integer o2) {return o2-o1;}});System.out.println("\nCollections.sort从大到小排序以后的list为:");for(int i = 0;i<list.size();i++){System.out.print(list.get(i)+" ");}
Test代码：
public class MessageCons {public static void main(String[] args) {List<Integer> list = new ArrayList<Integer>();list.add(1);list.add(5);list.add(10);list.add(2);list.add(11);list.add(55);list.add(8);System.out.println("原始list为:");for(int i = 0;i<list.size();i++){System.out.print(list.get(i)+" ");}Collections.sort(list);//从小到大进行排序System.out.println("\nCollections.sort从小到大排序以后的list为:");for(int i = 0;i<list.size();i++){System.out.print(list.get(i)+" ");}Collections.sort(list,new Comparator<Integer>() {@Overridepublic int compare(Integer o1, Integer o2) {// TODO Auto-generated method stubreturn o2-o1;}});System.out.println("\nCollections.sort从大到小排序以后的list为:");for(int i = 0;i<list.size();i++){System.out.print(list.get(i)+" ");}//Collections.sort(list,2,list.size());}}
