集合多层嵌套使用

不念不忘少年蓝@ 2022-05-16 03:20 257阅读 0赞

package com.cnd06;
    
    import java.util.ArrayList;
    import java.util.HashMap;
    import java.util.Set;
    
    /**
     * 集合多层嵌套代码体现
     * 
     * @author ndci
     *
     */
    public class HashDemo {
    	public static void main(String[] args) {
    		HashMap<String, HashMap<String, ArrayList<Student>>> czbkMap = new HashMap<String, HashMap<String, ArrayList<Student>>>();
    
    		// czbk北京校区
    		HashMap<String, ArrayList<Student>> bjMap = new HashMap<String, ArrayList<Student>>();
    		// czbk北京校区->基础班
    		ArrayList<Student> array1 = new ArrayList<Student>();
    		Student s1 = new Student("李月", 20);
    		Student s2 = new Student("赵毅", 22);
    		array1.add(s1);
    		array1.add(s2);
    		bjMap.put("基础班", array1);
    		// czbk北京校区->就业班
    		ArrayList<Student> array2 = new ArrayList<Student>();
    		Student s3 = new Student("钱龙", 21);
    		Student s4 = new Student("王军", 24);
    		array2.add(s3);
    		array2.add(s4);
    		bjMap.put("就业班", array2);
    		czbkMap.put("北京校区", bjMap);
    
    		// czbk上海校区
    		HashMap<String, ArrayList<Student>> shMap = new HashMap<String, ArrayList<Student>>();
    		// czbk上海校区->基础班
    		ArrayList<Student> array3 = new ArrayList<Student>();
    		Student s5 = new Student("李玉龙", 25);
    		Student s6 = new Student("王昭君", 26);
    		array3.add(s5);
    		array3.add(s6);
    		shMap.put("基础班", array3);
    		// czbk上海校区->就业班
    		ArrayList<Student> array4 = new ArrayList<Student>();
    		Student s7 = new Student("唐静", 25);
    		Student s8 = new Student("朱张", 27);
    		array4.add(s7);
    		array4.add(s8);
    		shMap.put("就业班", array4);
    		czbkMap.put("上海校区", shMap);
    
    		// 遍历集合
    		Set<String> czbkMapSet = czbkMap.keySet();
    		for (String key : czbkMapSet) {
    			System.out.println(key);
    			HashMap<String, ArrayList<Student>> czbkMapValue = czbkMap.get(key);
    			Set<String> czbkMapValueSet=czbkMapValue.keySet();
    			for(String key2:czbkMapValueSet) {
    				System.out.println("\t"+key2);
    				ArrayList<Student> arraylist=czbkMapValue.get(key2);
    				for(Student s:arraylist) {
    					System.out.println("\t\t"+s.getName()+"-----"+s.getAge());
    				}
    			}
    
    		}
    		
    		
    
    	}
    
    }