Warning: file_get_contents(/data/phpspider/zhask/data//catemap/9/java/305.json): failed to open stream: No such file or directory in /data/phpspider/zhask/libs/function.php on line 167

Warning: Invalid argument supplied for foreach() in /data/phpspider/zhask/libs/tag.function.php on line 1116

Notice: Undefined index: in /data/phpspider/zhask/libs/function.php on line 180

Warning: array_chunk() expects parameter 1 to be array, null given in /data/phpspider/zhask/libs/function.php on line 181
如何用Gson-java解析这个转义的Json?_Java_Json_Gson - Fatal编程技术网

如何用Gson-java解析这个转义的Json?

如何用Gson-java解析这个转义的Json?,java,json,gson,Java,Json,Gson,因此,我得到的回答如下,我无法控制: { "message": "someName someLastName has sent you a question", "parameters": "{\"firstName\":\"someName\",\"lastName\":\"someLastName\"}", "id": 141 } 乍一看,这似乎很简单,但parameters元素需要作为json对象来读取,而我一生都无法解决如何做到这一点。这就是我目前正在尝试的:

因此,我得到的回答如下,我无法控制:

{
    "message": "someName someLastName has sent you a question",
    "parameters": "{\"firstName\":\"someName\",\"lastName\":\"someLastName\"}",
    "id": 141
}
乍一看,这似乎很简单,但parameters元素需要作为json对象来读取,而我一生都无法解决如何做到这一点。这就是我目前正在尝试的:

JsonObject parameters = data.getAsJsonObject().get("parameters").getAsJsonObject();
/throws java.lang.IllegalStateException: Not a JSON Object: "{\"firstName\":\"someName\",\"lastName\":\"someLastName\"}"
所以我试着:

String elementToString = data.getAsJsonObject().get("parameters").toString().replace("\\\"", "\"");
JsonObject parameters = new Gson().fromJson(elementToString, JsonElement.class).getAsJsonObject();
//throws com.google.gson.JsonSyntaxException: com.google.gson.stream.MalformedJsonException: Use JsonReader.setLenient(true) to accept malformed JSON at line 1 column 5 path $
数据所在的位置(通常从服务器提取):

这肯定不是一个难题吗?

这里有什么

"parameters": "{\"firstName\":\"someName\",\"lastName\":\"someLastName\"}",
是一个JSON对,其中名称(始终是JSON字符串)和值都是JSON字符串。该值是可以解释为JSON对象的字符串。那么就这么做吧

String jsonString = data.getAsJsonObject().get("parameters").getAsJsonPrimitive().getAsString(); 
JsonObject parameters = gson.fromJson(jsonString, JsonObject.class);

以下

Gson gson = new Gson();
JsonElement data = gson
        .fromJson("  {\n" + "    \"message\": \"someName someLastName has sent you a question\",\n"
                + "    \"parameters\": \"{\\\"firstName\\\":\\\"someName\\\",\\\"lastName\\\":\\\"someLastName\\\"}\",\n"
                + "    \"id\": 141\n" + "  }", JsonElement.class);
String jsonString = data.getAsJsonObject().get("parameters").getAsJsonPrimitive().getAsString(); 
JsonObject parameters = gson.fromJson(jsonString, JsonObject.class);
System.out.println(parameters);
打印该
JsonObject

{"firstName":"someName","lastName":"someLastName"}

我用于获取具体对象的解决方案(不管它是对象还是转义字符串)是如下所示的反序列化器:

public class MyDeserializer implements JsonDeserializer<MyThing> {

    @Override
    public MyThing deserialize(JsonElement element, Type typeOfT, JsonDeserializationContext context) throws JsonParseException {
        if (element.isJsonObject()) {
            //Note Don't use a gson that contains this deserializer or it will recurse forever
            return new Gson().fromJson(element.getAsJsonObject(), MyThing.class);
        } else {
            String str = element.getAsJsonPrimitive().getAsString();
            return gson.get().fromJson(str, MyThing.class);
        }
    }    

}
公共类MyDeserializer实现JsonDeserializer{
@凌驾
公共神话反序列化(JsonElement元素,类型typeOfT,JsonDeserializationContext)引发JsonParseException{
if(element.isJsonObject()){
//注意不要使用包含此反序列化器的gson,否则它将永远递归
返回新的Gson().fromJson(element.getAsJsonObject(),MyThing.class);
}否则{
字符串str=element.getAsJsonPrimitive().getAsString();
返回gson.get().fromJson(str,MyThing.class);
}
}    
}
public class MyDeserializer implements JsonDeserializer<MyThing> {

    @Override
    public MyThing deserialize(JsonElement element, Type typeOfT, JsonDeserializationContext context) throws JsonParseException {
        if (element.isJsonObject()) {
            //Note Don't use a gson that contains this deserializer or it will recurse forever
            return new Gson().fromJson(element.getAsJsonObject(), MyThing.class);
        } else {
            String str = element.getAsJsonPrimitive().getAsString();
            return gson.get().fromJson(str, MyThing.class);
        }
    }    

}