吴裕雄--天生自然java开发常用类库学习笔记：集合工具类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) ;
        
    }
};