代碼需求

?　　想從

[abcde, cba, aa, zzz, cba, nbaa]

?

　　變成

[aa, cba, cba, zzz, nbaa, abcde]

?

?

?

?

?

?

?

?

?

?

CollectionsDemo.java

package zhouls.bigdata.DataFeatureSelection.test;import java.util.ArrayList; import java.util.Collections; import java.util.Comparator; import java.util.List; import java.util.TreeSet;import zhouls.bigdata.DataFeatureSelection.test.ComparatorByLength;public class CollectionsDemo {/*** @param args*/public static void main(String[] args) {/** Collections：是集合框架的工具類。* 里面的方法都是靜態的。*/demo();}public static void demo(){List<String> list = new ArrayList<String>();list.add("abcde");list.add("cba");list.add("aa");list.add("zzz");list.add("cba");list.add("nbaa");System.out.println(list);//對list集合進行指定順序的排序。 Collections.sort(list);mySort(list);mySort(list,new ComparatorByLength());Collections.sort(list,new ComparatorByLength());System.out.println(list);}public static <T> void mySort(List<T> list,Comparator<? super T> comp){for (int i = 0; i < list.size()-1; i++) {for (int j = i+1; j < list.size(); j++) {if(comp.compare(list.get(i), list.get(j))>0){T temp = list.get(i);list.set(i, list.get(j));list.set(j, temp);Collections.swap(list, i, j);}}}}public static <T extends Comparable<? super T>> void mySort(List<T> list){for (int i = 0; i < list.size()-1; i++) {for (int j = i+1; j < list.size(); j++) {if(list.get(i).compareTo(list.get(j))>0){ // T temp = list.get(i); // list.set(i, list.get(j)); // list.set(j, temp); Collections.swap(list, i, j);}}}} }

?

?

?

?

?

ComparatorByLength.java

package zhouls.bigdata.DataFeatureSelection.test;import java.util.Comparator;public class ComparatorByLength implements Comparator<String> {public int compare(String o1, String o2) {int temp = o1.length() - o2.length();return temp==0?o1.compareTo(o2): temp;} }

總結

以上是生活随笔為你收集整理的Collections练习之按照字符串长度进行排序的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯，歡迎將生活随笔推薦給好友。