如何将泛型或原始类型列表转换为字符串数组

Question

我正在制作通用或原始类型数据的列表，并尝试将其存储在String数组中，但是失败-

线程“主”中的异常java.lang.ArrayStoreException

这是代码片段，在此函数中，我试图将原始类型转换为字符串数组，但面对给定的数组，请您采取以下给定的示例并指导我在这里做错了什么-

 public class Parsing {


        public static void main(String[] args) throws JsonParseException, JsonMappingException, IOException {

            //List<JsonGen> jsongenShow = null;
            String url1 = "http://www.xxxxxxxx.com/radish/v20/dol/home/carousels/shows.json";
            List[] nwDetails = getShowNWdetailsParser(jsongenShow, url1);

        }


        @SuppressWarnings("rawtypes")
        public static List[] getShowNWdetailsParser (List<JsonGen> jsongenShow, String url ) throws JsonParseException, JsonMappingException, IOException
        {
            URL jsonUrl = new URL(url);
            ObjectMapper objmapper = new ObjectMapper();
            jsongenShow = objmapper.readValue(jsonUrl, new TypeReference<List<JsonGen>>() {});
            List [] shows = new List [jsongenShow.size()]; 

             String[] showsArr = new String[jsongenShow.size()];
             showsArr= (String[])jsongenShow.toArray(showsArr);

            for (int i=0; i == jsongenShow.size(); i++ ){

                System.out.println(showsArr[i]);
            }
int i = 0;
        for(JsonGen element : jsongenShow) {
            shows[i]=element.getNetworks();

            i++;
            }
        for(int j =0; j<shows.length;j++)
        {
            System.out.println(showsArr[j]);

        }


            return shows;   
        }

    }

Answer 1

Java无法自动为您将对象转换为String。 您必须遍历源列表并填充目标数组，然后自己将JsonGen映射到String。

非常不幸的是，API完全允许您的代码进行编译

Answer 2

经过一番实验，我终于找到了解决之道。

 @SuppressWarnings("rawtypes")
    public static String[] getShowNWdetailsParser (List<JsonGen> jsongenShow, String url ) throws JsonParseException, JsonMappingException, IOException
    {
        URL jsonUrl = new URL(url);
        ObjectMapper objmapper = new ObjectMapper();
        List<JsonGen> jsongenShow_1 = objmapper.readValue(jsonUrl, new TypeReference<List<JsonGen>>() {});
        List [] shows = new List [jsongenShow_1.size()]; 
        String[] showsArr = new String[jsongenShow_1.size()];
        for(JsonGen element : jsongenShow_1) {
            shows[i]=element.getNetworks();
            showsArr[i]=shows[i].toString();
            i++;
            }
        for(int j =0; j<shows.length;j++)
        {
            System.out.println(showsArr[j]);

        }

        return showsArr;    
    }