_107_Java_Collection工具类的使用Collections以及Enumeration

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import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;


/*
 * 操作Collection以及Map的工具类：Collections
 * 面试题：区分Collection与Collections
 * */
public class _001_CollectionUtils_13_13 {

	
	public static void main(String[] args){
		List li= new ArrayList<>();
		li.add(12);
		li.add(11);
		li.add(10);
		li.add(15);
		li.add(17);
		li.add(10);
		
		for(Object ob:li) {
			System.out.print(ob+" ");
		}
		System.out.println("\n---------reverse-----------");
		
		Collections.reverse(li);
		for(Object ob:li) {
			System.out.print(ob+" ");
		}
		System.out.println("\n---------shuffle-----------");
		
		Collections.shuffle(li);
		for(Object ob:li) {
			System.out.print(ob+" ");
		}
		System.out.println("\n----------sort----------");
		
		Collections.sort(li);
		for(Object ob:li) {
			System.out.print(ob+" ");
		}
		System.out.println("\n---------swap-----------");
		
		Collections.swap(li, 0,li.size()-1);
		for(Object ob:li) {
			System.out.print(ob+" ");
		}
		System.out.println("\n--------max------------");
		
		Object max = Collections.max(li);
		System.out.println(max);
		System.out.println("---------frequency-----------");
		
		int frequency = Collections.frequency(li, 10);
		System.out.println(frequency);
		
		System.out.println("---------copy-----------");
		//List liA=new ArrayList<>(); 错误的实现方式
		List liA=Arrays.asList(new Object[li.size()]);
		Collections.copy(liA,li);
		for(Object ob:liA) {
			System.out.print(ob+" ");
		}
		System.out.println("\n---------replaceAll-----------");
		
		Collections.replaceAll(li, 10, 18);
		for(Object ob:li) {
			System.out.print(ob+" ");
		}
		System.out.println("\n--------synchronizedList------------");
		
		//通过如下的方法保证list线程的安全性
		List liB = Collections.synchronizedList(li);
		System.out.println(liB);
		
	}
}

 输出结果：

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Enumeration: