GSON转换自

Question

您好，我正在尝试使用GSON类来转换以下Json字符串。

{"data":
     {"detections":
                  [
                    [ 
                     {"language":"en","isReliable":false,"confidence":0.9759119}
                    ]
                  ]
      }
}

我得到了这个错误。com.google.gson.JsonSyntaxException: java.lang.IllegalStateException:预期为BEGIN_ARRAY，但在com.google.gson.Gson.fromJson(Gson.java:731)时为BEGIN_OBJECT

它的类层次结构应该是什么？

Answer 1

也许下面的例子给出了一个足够的想法。

import java.io.FileReader;
import java.math.BigDecimal;

import com.google.gson.Gson;

public class GsonFoo
{
  public static void main(String[] args) throws Exception
  {
    Gson gson = new Gson();
    Bar bar = gson.fromJson(new FileReader("input.json"), Bar.class);

    System.out.println(bar.data.detections[0][0]);
    // output:
    // Detection: language=en, isReliable=false, confidence=0.9759119
  }
}

class Bar
{
  Data data;
}

class Data
{
  Detection[][] detections;
}

class Detection
{
  Language language;
  boolean isReliable;
  BigDecimal confidence;

  @Override
  public String toString()
  {
    return String.format("Detection: language=%s, isReliable=%s, confidence=%s", language, isReliable, confidence);
  }
}

enum Language
{
  en, fr;
}