The most complete history HashMap traversal

java Hashmap Map TreeMap traverse several ways, the most complete whole network, the whole network of the strongest

 

 

package Collec2;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;

public class Test1 {

    public static void main(String[] args) {
        HashMap<Student, String> hashmap_88 = new HashMap<Student, String>();
        hashmap_88.put(new Student("张三", 23), "北京");
        hashmap_88.put(new Student("李四", 24), "南京");
        HashMap<Student, String> = hashmap_99 new new HashMap <Student, String> (); 
        hashmap_99.put ( new new Student ( "King of Five", 23), "Shanghai" ); 
        hashmap_99.put ( new new Student ( "Zhao six", 24 ), "Shenzhen" ); 
        HashMap <HashMap <Student, String>, String> HM = new new HashMap <HashMap <Student, String>, String> (); 
        hm.put (hashmap_88, "on the basis of 88 classes" ); 
        hm.put (hashmap_99, "on the basis of 99 classes" ); 
        
        System.out.println ( "traversing a way" ); 
        the Set <HashMap <Student,String>> ks = hm.keySet();
        Iterator<HashMap<Student, String>> it1 = ks.iterator();
        while(it1.hasNext()) {
            HashMap<Student,String> next_stu_value = it1.next();
            Set<Student> stu_set = next_stu_value.keySet();
            Iterator<Student> stu_it = stu_set.iterator();
            System.out.println(hm.get(next_stu_value)+"有以下学生");
            while(stu_it.hasNext()) {
                Student student = stu_it.next();
                System.out.println("个人信息"+student);
            }
        }
        
        System.out.println("遍历方式二");
        for (HashMap<Student, String> hashMap : hm.keySet()) {
            System.out.println(hm.get(hashMap)+"有以下学生");
            for (Student stu : hashMap.keySet()) {
                System.out.println("个人信息"+stu);
            }
        }
        System.out.println("遍历方式三");
        Set<HashMap<Student,String>> x=hm.keySet();
        for(Iterator<HashMap<Student,String>> it= x.iterator();it.hasNext();) {
             HashMap<Student, String> stu_map_value = it.next();
             System.out.println(hm.get(stu_map_value)+"有以下学生");
            for( Iterator<Student> it2 = stu_map_value.keySet().iterator();it2.hasNext();) {
                Student student = it2.next();
                System.out.println("个人信息"+student);
            }
        }
        System.out.println("遍历方式四");
        Set<Entry<HashMap<Student,String>,String>> entrySet = hm.entrySet();
        Iterator<Entry<HashMap<Student, String>, String>> itentry = entrySet.iterator();
        while(itentry.hasNext()) {
            Entry<HashMap<Student, String>, String> entry = itentry.next();
            HashMap<Student,String> map = entry.getKey();
            System.out.println(entry.getValue()+"有以下学生");
            Iterator<Entry<Student, String>> iterator = map.entrySet().iterator();
             while(iterator.hasNext()) {
                 Entry<Student, String> next = iterator.next();
                    System.out.println("个人信息"+next.getKey()+" "+next.getValue());
             }
        }
        System.out.println("Traversal five" );
         for (of Map.Entry <the HashMap <Student, String>, String> entry: hm.entrySet ()) { 
            System.out.println (entry.getValue () + "following student" );
             for (of Map.Entry <Student, String> STU: entry.getKey () the entrySet ().) { 
                System.out.println ( "personal information" stu.getKey + () + "" + stu.getValue ()); 
            } 
        } 
        System.out.println ( "traversal six" ); 
        hm.forEach ((K, V) -> { 
            System.out.println (V + "following student" ); 
            K.forEach ((sub_K,sub_V)->{
                System.out.println("个人信息"+sub_K+" "+sub_V);
            });
        });
        
        Iterator<HashMap<Student, String>> ite2 = hm.keySet().iterator();
        while(ite2.hasNext()) {
            HashMap<Student,String> next = ite2.next();
            Iterator<Entry<Student, String>> iterator = next.entrySet().iterator();
            while(iterator.hasNext()) {
                Entry<Student, String> entry = iterator.next();
                if(entry.getValue().equals("深圳")) {
                    iterator.remove();
                } 
            }
        } 
        System.out.println ( "- = -----------------------" ); 
        hm.forEach ((K, V) -> { 
            the System .out.println (V + "following student" ); 
            K.forEach ((sub_K, sub_V) -> { 
                System.out.println ( "personal information" sub_K + + "" + sub_V); 
            }); 
        }); 
        
        
    } 
}