java - 将两种类型的数组转换为HashMap、TreeMap、LinkedHashMap

Question

创建数组:

{int, String}, {String, String}, {int, long}, {String,boolean}, {String, double}, {int, class Car}, {String, class Car}

转换为HashMap、TreeMap、LinkedHashMap

这是汽车类:

public class Car implements Comparable{

    int id;
    String car_name;
    String number;

    public Car(int id, String car_name, String number) {
        this.id = id;
        this.car_name = car_name;
        this.number = number;
    }

    @Override
    public String toString() {
        return "Car{" +
                "id='" + id + '\'' +
                ", car_name='" + car_name + '\'' +
                ", number='" + number + '\'' +
                '}';
    }
}

这是我的代码:

public class Main {

    private static HashMap<Integer,String> toHM(Object[][] a){
        HashMap<Integer,String> h = new HashMap<>();

        for (Object[] o : a){
            h.put((Integer) o[0], (String) o[1]);
        }
        return h;
    }

    private static HashMap<Integer,String> toLHM(Object[][] a){
        HashMap<Integer,String> h = new LinkedHashMap<>();

        for (Object[] o : a){
            h.put((Integer) o[0], (String) o[1]);
        }
        return h;
    }

    private static TreeMap<Integer,String> toTM(Object[][] a){
        TreeMap<Integer,String> h = new TreeMap<>();

        for (Object[] o : a){
            h.put((Integer) o[0], (String) o[1]);
        }
        return h;
    }



    public static void main(String[] args) {

        Object[][] a = new Object[2][2];
        a[0][0] = 1;
        a[0][1] = "test";
        a[1][0] = 2;
        a[1][1] = "other test";

       HashMap<Integer,String> aHM = toHM(a);
       HashMap<Integer,String> aLHH = toLHM(a);
       TreeMap<Integer,String> aTM = toTM(a);

    }
}

这个代码正确吗？也许，在该代码中使用泛型会更好吗？ 我知道如何解决这个问题吗？

Answer 1

检查一下:

@SuppressWarnings("unchecked")
public static <S, T1, T2> S convert(Object[] inputobject, Class<S> mapType,
        Class<T1> keyType, Class<T2> valueType)
        throws IllegalAccessException, InstantiationException {
    Map<T1, T2> map = (Map<T1, T2>) mapType.newInstance();
    map.put((T1) inputobject[0], (T2) inputobject[1]);
    return (S) map;
}

• inputObject:对象数组
• ma​​pType:例如 map 的类别。 HashMap 、树形图等
• keyType :键的类别，例如。字符串、整数等
• valueType:值类别

示例输入:

Object[] obj = new Object[] { 1, "test" };
System.out.println(convert(obj, HashMap.class, Integer.class, String.class));

示例输出:

{1=test}

我希望这会起作用。