Java Collections工具类

package toolClass.Collections.Demo;import java.util.ArrayList;import java.util.Collections;import java.util.Comparator;import java.util.Iterator;import org.w3c.dom.stylesheets.LinkStyle;import com.sun.xml.internal.bind.v2.schemagen.xmlschema.List;import sun.security.action.GetBooleanAction;import toolClass.Comparator.Demo.ComparatorByLength;public class ColletctionsDemo {public static void main(String[] args) {/* * Collections 是集合框架的工具类 里面的方法都是静态的 */demo_1();}public static void  demo_1() {java.util.List<String>list=new ArrayList<String>();list.add("abcde");list.add("cba");list.add("aa");list.add("zzz");list.add("nbaa");System.out.println(list);//对list 集合进行指定顺序的排序//Collections.sort(list);//mySort(list);//mySort(list, new ComparatorByLength());Collections.sort(list, new ComparatorByLength());System.out.println(list);}public static <T>void mySort(java.util.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(java.util.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);}}}}*/}