java - 如何获取json数组中数组内部键的值

Question

这是我得到的字符串，我想将其解析为 json 并获取“s”、“o”、“c”和“p”的值。

{
    "head": {
        "vars": [
            "s",
            "c",
            "o",
            "p"
        ]
    },
    "results": {
        "bindings": [
            {
                "s": {
                    "type": "uri",
                    "value": "http://example.org/data/window"
                },
                "c": {
                    "type": "uri",
                    "value": "http://www.w3.org/ns/sosa/FeatureOfInterest"
                },
                "o": {
                    "type": "uri",
                    "value": "http://example.org/data/window104state"
                },
                "p": {
                    "type": "uri",
                    "value": "http://www.w3.org/ns/ssn/hasProperty"
                }
            },
                        {
                "s": {
                    "type": "uri",
                    "value": "http://example.org/data/earth"
                },
                "c": {
                    "type": "uri",
                    "value": "http://www.w3.org/ns/sosa/FeatureOfInterest"
                },
                "o": {
                    "type": "uri",
                    "value": "http://example.org/data/VCAB-DP1-BP-40location"
                },
                "p": {
                    "type": "uri",
                    "value": "http://www.w3.org/ns/sosa/hasSample"
                }
            }
        ]
    }
}

这是我迄今为止尝试过的代码:

JsonParser jsonParser =  new JsonParser();
JsonElement element = jsonParser.parse(str);
JsonObject obj = element.getAsJsonObject();
JsonObject results = obj.get("results").getAsJsonObject();
for(Map.Entry<String, JsonElement> entry : results.entrySet()) {
            JsonArray array = entry.getValue().getAsJsonObject().getAsJsonArray("bindings");
            for (JsonElement jsonElement : array) {
                 for (Map.Entry<String, JsonElement> entry1 : jsonElement.getAsJsonObject().entrySet()) {
                     System.out.println("Key = " + entry1.getKey() + " Value = " + entry1.getValue() );
                }
            }

我想要得到的是内部数组的值，如下所示:“s”:“http://example.org/data/earth”“c”:“http://www.w3.org/ns/sosa/FeatureOfInterest”ETC。相反，我收到一个错误:

Exception in thread "main" java.lang.IllegalStateException: Not a JSON Object: [{"s":{"type":"uri","value":"http://example.org/data/window"},"c":{"type":"uri","value":"http://www.w3.org/ns/sosa/FeatureOfInterest"},"o":{"type":"uri","value":"http://example.org/data/window104state"},

(整个字符串)。

更新感谢@Deadpool，我设法获取了这些值，但现在我需要获取绑定(bind)的“内部”值，这意味着每个绑定(bind)的“值”部分(s、c、p 和 o)。我只需要这部分而不是“类型”部分。这是感谢 @Deadpool 的结果:

Key = s Value = {"type":"uri","value":"http://example.org/data/window"}
Key = c Value = {"type":"uri","value":"http://www.w3.org/ns/sosa/FeatureOfInterest"}
Key = p Value = {"type":"uri","value":"http://www.w3.org/ns/ssn/hasProperty"}
Key = o Value = {"type":"uri","value":"http://example.org/data/window104state"}

解决方案好的，对于那些感兴趣的人，我设法得到了所需的声明:

System.out.println("Key = " + entry1.getKey() + " Value = " + entry1.getValue().getAsJsonObject().get("value"));

这就是期望的结果:

Key = s Value = "http://example.org/data/earth"
Key = c Value = "http://www.w3.org/ns/sosa/FeatureOfInterest"
Key = o Value = "http://example.org/data/VCAB-DP1-BP-40location"
Key = p Value = "http://www.w3.org/ns/sosa/hasSample"

Answer 1

问题出在这句话中 bindings 是一个 JsonArray，直接获取为 JsonArray

JsonArray array = entry.getValue().getAsJsonObject().getAsJsonArray("bindings");

解决方案

for(Map.Entry<String, JsonElement> entry : results.entrySet()) {
        JsonArray array = entry.getValue().getAsJsonArray();
        for (JsonElement jsonElement : array) {
             for (Map.Entry<String, JsonElement> entry1 : jsonElement.getAsJsonObject().entrySet()) {
                 System.out.println("Key = " + entry1.getKey() + " Value = " + entry1.getValue() );
            }
        }