Question

我正在尝试从Nutritionix API反序列化JSON响应。当我尝试反序列化对象时，我不断收到HTTP状态500 - 请求处理失败;嵌套异常是java.lang.ClassCastException：java.lang.String无法强制转换为java.util.Map错误。我非常困惑，不知道为什么会发生这种情况，因为似乎我得到了有效的JSON响应，但我不确定。

public class CallSearch {

    String value;

    public CallSearch(String search){
        value = search.replace(" ", "%20");
    }
    public FullResponse search() throws ClientProtocolException, IOException{

        CloseableHttpClient client = HttpClients.createDefault();
        HttpGet getProducts = new HttpGet("https://api.nutritionix.com/v1_1/search/"+ value +"?results=0%3A6&cal_min=0&cal_max=50000&fields=item_name%2Citem_id&appId=ac23ceb3&appKey=e2b579c55b4857157fc6045d6296b532");
        CloseableHttpResponse productResponse = client.execute(getProducts);
        String entityString = EntityUtils.toString(productResponse.getEntity());
        FullResponse test = new JSONDeserializer<FullResponse>().deserialize(entityString,FullResponse.class);

        return test;
    }
}

我为反序列化而创建的类如下

public class FullResponse {

    String total_hits;
    String max_score;
    List<Hits> hits;

    public FullResponse(){

    }

    public String getTotal_hits() {
        return total_hits;
    }

    public void setTotal_hits(String total_hits) {
        this.total_hits = total_hits;
    }

    public String getMax_score() {
        return max_score;
    }

    public void setMax_score(String max_score) {
        this.max_score = max_score;
    }

    public List<Hits> getHits() {
        return hits;
    }

    public void setHits(List<Hits> hits) {
        this.hits = hits;
    }

Hits Class是完整响应中的列表

public class Hits {

       String _index;
       String _type;
       String _id;
       String _score;
       List<Fields> fields;

       public Hits(){

       }

        public String get_index() {
        return _index;
    }

    public void set_index(String _index) {
        this._index = _index;
    }

    public String get_type() {
        return _type;
    }

    public void set_type(String _type) {
        this._type = _type;
    }

    public String get_id() {
        return _id;
    }

    public void set_id(String _id) {
        this._id = _id;
    }

    public String get_score() {
        return _score;
    }

    public void set_score(String _score) {
        this._score = _score;
    }

    public List<Fields> getFields() {
        return fields;
    }

    public void setFields(List<Fields> fields) {
        this.fields = fields;
    }
}

最后是Fields类：

public class Fields {

    String item_name;

    public Fields(){

    }

    public String getField(){
        return item_name;
    }
    public void setField(String name){
        item_name=name;
    }
}

对我可能出错的地方的任何帮助将不胜感激。感谢

好的，我做了更改，这是我得到的JSON响应

{
"total_hits":11025,
"max_score":11.122117,
"hits":[{
"_index":"nixproductionv13",
"_type":"item",
"_id":"513fceb375b8dbbc210000e4",
"_score":11.122117,
"fields":{"item_name":"Whole Milk - 1 tbsp"}},

{"_index":"nixproductionv13",
"_type":"item",
"_id":"513fceb375b8dbbc2100017b",
"_score":10.7038355,
"fields":{"item_name":"2% Milk - 1 cup"}},

{"_index":"nixproductionv13",
"_type":"item",
"_id":"513fceb375b8dbbc210000f3",
"_score":10.7038355,
"fields":{"item_name":"1% Milk - 1 cup"}},

{"_index":"nixproductionv13",
"_type":"item",
"_id":"513fceb375b8dbbc210000fb",
"_score":10.689078,
"fields":{"item_name":"Skim Milk - 1 cup"}},

{"_index":"nixproductionv13",
"_type":"item",
"_id":"513fceb375b8dbbc210000e3",
"_score":10.65872,
"fields":{"item_name":"Whole Milk - 1 fl oz"}},

{"_index":"nixproductionv13",
"_type":"item",
"_id":"513fceb375b8dbbc2100017a",
"_score":10.392,
"fields":{"item_name":"2% Milk - 1 quart"}}]}

现在导致嵌套异常是java.lang.IllegalArgumentException：参数类型不匹配

org.springframework.web.util.NestedServletException：Request 处理失败;嵌套异常是 java.lang.IllegalArgumentException：参数类型不匹配 org.springframework.web.servlet.FrameworkServlet.processRequest（FrameworkServlet.java:894） org.springframework.web.servlet.FrameworkServlet.doGet（FrameworkServlet.java:778） javax.servlet.http.HttpServlet.service（HttpServlet.java:621） javax.servlet.http.HttpServlet.service（HttpServlet.java:728） org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:330） org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke（FilterSecurityInterceptor.java:118） org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter（FilterSecurityInterceptor.java:84） org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342） org.springframework.security.web.access.ExceptionTranslationFilter.doFilter（ExceptionTranslationFilter.java:113） org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342） org.springframework.security.web.session.SessionManagementFilter.doFilter（SessionManagementFilter.java:103） org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342） org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter（AnonymousAuthenticationFilter.java:113） org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342） org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter（SecurityContextHolderAwareRequestFilter.java:54） org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342） org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter（RequestCacheAwareFilter.java:45） org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342） org.springframework.security.web.authentication.www.BasicAuthenticationFilter.doFilter（BasicAuthenticationFilter.java:150） org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342） org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter（AbstractAuthenticationProcessingFilter.java:183） org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342） org.springframework.security.web.authentication.logout.LogoutFilter.doFilter（LogoutFilter.java:105） org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342） org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter（SecurityContextPersistenceFilter.java:87） org.springframework.security.web.FilterChainProxy $ VirtualFilterChain.doFilter（FilterChainProxy.java:342） org.springframework.security.web.FilterChainProxy.doFilterInternal（FilterChainProxy.java:192） org.springframework.security.web.FilterChainProxy.doFilter（FilterChainProxy.java:160） org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate（DelegatingFilterProxy.java:346） org.springframework.web.filter.DelegatingFilterProxy.doFilter（DelegatingFilterProxy.java:259）

Answer 1

这不会解决所有问题，但会让我们走上正轨

String entityString = productResponse.getEntity().toString();

应该是

String entityString = EntityUtils.toString(productResponse.getEntity());

EntityUtils.toString()个州的javadoc

读取实体的内容并将其作为String返回。内容使用实体中的字符集（如果有）转换，失败那就是“ISO-8859-1”。

当你这样做时

productResponse.getEntity().toString();

您正在调用toString()类的Object方法，ResponseEntityWrapper继承该方法。这只会返回String值org.apache.http.impl.execchain.ResponseEntityWrapper@8f6b087，它不是HTTP响应的主体。

反序列化问题

1 个答案: