JAVA---HashMap的四种遍历方式，未加泛型

public class HashMapDemo {
    public static void main(String[] args) {
        HashMap hashMap = new HashMap();
        hashMap.put("小吉祥草王", "纳西妲");
        hashMap.put("岩王爷", "摩拉克斯");
        hashMap.put("雷神", "巴尔");
        //HashMap的四种遍历方式
        //method1(hashMap);//forEach的lambda表达式遍历
        //method2(hashMap);//keySet遍历
        //method3(hashMap);//迭代器遍历
        method4(hashMap);//entrySet遍历
    }

    private static void method4(HashMap hashMap) {
        Set entrySet = hashMap.entrySet();
        for (Object obj :entrySet) {
            Map.Entry entry = (Map.Entry) obj;
            System.out.println(entry.getKey()+"-"+entry.getValue());
        }
    }

    private static void method3(HashMap hashMap) {
        Set entrySet = hashMap.entrySet();
        Iterator iterator = entrySet.iterator();
        while (iterator.hasNext()) {
            //Object entry = iterator.next();
            // System.out.println(entry);

             Object entry = iterator.next();
            Map.Entry m = (Map.Entry) entry;
            System.out.println(m.getKey() + "-" + m.getValue());
        }
    }

    private static void method2(HashMap hashMap) {
        Set set = hashMap.keySet();
        for (Object objKey : set) {
            System.out.println(objKey + "-" + hashMap.get(objKey));
        }
        System.out.println("--------values-----");
        Collection values = hashMap.values();
        for (Object objValue : values) {
            System.out.println(objValue);
        }
    }

    private static void method1(HashMap hashMap) {
        System.out.println("forEach方便遍历");
        hashMap.forEach((key, value) -> {
            System.out.println(key + "-" + value);
        });
    }
}