Collections

import java.util.Collections ;
import java.util.List ;
import java.util.Set ;
public class CollectionsDemo01{
	public static void main(String args[]){
		List<String> allList = Collections.emptyList() ;	// 返回空的 List集合
		Set<String> allSet = Collections.emptySet() ;	// 返回空的 List集合
		allList.add("Hello") ;	// 加入数据
	}
};



import java.util.Collections ;
import java.util.List ;
import java.util.ArrayList ;
import java.util.Iterator ;
public class CollectionsDemo02{
	public static void main(String args[]){
		List<String> all = new ArrayList<String>() ;	// 返回空的 List集合
		Collections.addAll(all,"MLDN","LXH","mldnjava") ;
		Iterator<String> iter = all.iterator() ;
		while(iter.hasNext()){
			System.out.print(iter.next() + "、") ;
		}
	}
};



import java.util.Collections ;
import java.util.List ;
import java.util.ArrayList ;
import java.util.Iterator ;
public class CollectionsDemo03{
	public static void main(String args[]){
		List<String> all = new ArrayList<String>() ;	// 返回空的 List集合
		Collections.addAll(all,"MLDN","LXH","mldnjava") ;
		Collections.reverse(all) ;	// 内容反转
		Iterator<String> iter = all.iterator() ;
		while(iter.hasNext()){
			System.out.print(iter.next() + "、") ;
		}
	}
};



import java.util.Collections ;
import java.util.List ;
import java.util.ArrayList ;
import java.util.Iterator ;
public class CollectionsDemo04{
	public static void main(String args[]){
		List<String> all = new ArrayList<String>() ;	// 返回空的 List集合
		Collections.addAll(all,"MLDN","LXH","mldnjava") ;
		int point = Collections.binarySearch(all,"LXH") ;	// 检索数据
		System.out.println("检索结果:" + point) ;
		
	}
};


import java.util.Collections ;
import java.util.List ;
import java.util.ArrayList ;
import java.util.Iterator ;
public class CollectionsDemo05{
	public static void main(String args[]){
		List<String> all = new ArrayList<String>() ;	// 返回空的 List集合
		Collections.addAll(all,"MLDN","LXH","mldnjava") ;
		if(Collections.replaceAll(all,"LXH","李兴华")){// 替换内容
			System.out.println("内容替换成功!") ;
		}
		System.out.print("替换之后的结果:") ;
		System.out.print(all) ;
		
	}
};



import java.util.Collections ;
import java.util.List ;
import java.util.ArrayList ;
import java.util.Iterator ;
public class CollectionsDemo06{
	public static void main(String args[]){
		List<String> all = new ArrayList<String>() ;	// 返回空的 List集合
		Collections.addAll(all,"1、MLDN","2、LXH","3、mldnjava") ;
		Collections.addAll(all,"B、www.mldn.cn") ;
		Collections.addAll(all,"A、www.mldnjava.cn") ;
		System.out.println("排序之前的集合:" + all) ;
		Collections.sort(all) ;
		System.out.println("排序之后的集合:" + all) ;
		
	}
};


import java.util.Collections ;
import java.util.List ;
import java.util.ArrayList ;
import java.util.Iterator ;
public class CollectionsDemo07{
	public static void main(String args[]){
		List<String> all = new ArrayList<String>() ;	// 返回空的 List集合
		Collections.addAll(all,"1、MLDN","2、LXH","3、mldnjava") ;
		System.out.println("交换之前的集合:" + all) ;
		Collections.swap(all,0,2) ;
		System.out.println("交换之后的集合:" + all) ;
		
	}
}
 

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