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Java 添加动态Hashmap键_Java - Fatal编程技术网

Java 添加动态Hashmap键

Java 添加动态Hashmap键,java,Java,我想问一下,我是否能够在java中添加动态hashmap键 比如说 ... String name = reader.next(); HashMap<String, Integer> map = new HashMap<>(); map.put(name, 1); 另外,如何循环使用hashmap打印hashmap中的所有键?要添加多个元素,请使用循环,如for循环 Scanner sc = new Scanner(System.in); HashMap<St

我想问一下,我是否能够在java中添加动态hashmap键

比如说

...
String name = reader.next();
HashMap<String, Integer> map = new HashMap<>();

map.put(name, 1); 

另外,如何循环使用hashmap打印hashmap中的所有键?

要添加多个元素,请使用循环,如for循环

Scanner sc = new Scanner(System.in);
HashMap<String, Integer> map = new HashMap();
int i = 1;
while(sc.hasNext()){
    String s = sc.nextLine();
    map.put(s, i++);
}
printMap(map);

该学习了。你怎么能在字符串参数中添加int呢?@女神我编辑了答案,忘了更改。现在可以了。
Scanner sc = new Scanner(System.in);
HashMap<String, Integer> map = new HashMap();
int i = 1;
while(sc.hasNext()){
    String s = sc.nextLine();
    map.put(s, i++);
}
printMap(map);
public static void printMap(Map mp) {
    Iterator it = mp.entrySet().iterator();
    while (it.hasNext()) {
        Map.Entry pair = (Map.Entry)it.next();
        System.out.println(pair.getKey() + " = " + pair.getValue());
    }
}