JAVA中HashMap遍历以及排序代码

- 日理万妓 2022-05-26 10:09 129阅读 0赞

# HashMap遍历 #

import java.util.HashMap;
    import java.util.Map;
    import java.util.Scanner;
    
    public class Main {
        public static void main(String[] args) {
    
                HashMap<String,String> map=new HashMap<String,String>();
                Scanner scanner=new Scanner(System.in);
                String name=scanner.next();
                String hobby=scanner.next();
                map.put(name, hobby);
                Collection list=map.values();//转换成集合都是values只有values，，要是都输出就是keyset
                Iterator it=list.iterator();
                while(it.hasNext())
                {
                    System.out.println(it.next());
                }
                System.out.println(map.get(name));
                map.remove(name);
                System.out.println(map.size());
        }
    }

# HashMap排序 #

import java.util.ArrayList;
    import java.util.Collections;
    import java.util.Comparator;
    import java.util.HashMap;
    import java.util.Iterator;
    import java.util.List;
    import java.util.Map;
    
    public class Main{ 
        public static void main(String[] args){
    
        HashMap<String,Integer> map=new HashMap<String,Integer>();
            map.put("Kobe",24);
            map.put("James",6);
            map.put("Durant",35);
            map.put("Anthony",7);
    
            List list=new ArrayList(map.keySet());
            //map变成集合list,对keyset进行排序,只有key(对新生成的list进行排序)
            Collections.sort(list, new Comparator<String>(){
            //list固定,按照String进行排序
                    @Override
                    public int compare(String o1, String o2) {
                        // TODO Auto-generated method stub
                        return o1.compareTo(o2);
                    }       
            });
            System.out.println(map.get("Kobe"));
                Iterator it=list.iterator();
                while(it.hasNext())
                {   
                 String s=(String) it.next();  
                    System.out.println(s+"="+map.get(s)); 
              }
    
        }
    }