Java JSON处理

我很难用Java处理下面的JSON，它是从外部Ansible playbook返回的：

{"Sample":
    {
        "tag_description":"abc","tag_category_id":"def","tag_id":"ghi"
    },
    "Sample1":
    {
        "tag_description":"jkl","tag_category_id":"mno","tag_id":"pqr"
    }
 }

我已经能够使用自定义反序列化程序成功解析JSON的一个部分，尽管它只得到第一个部分。任何想法都会受到极大的赞赏

@JsonComponent
public class TagSerializer extends JsonDeserializer<Tag> {



@Override
public Tag deserialize(JsonParser jsonParser,
                        DeserializationContext deserializationContext) throws IOException,
        JsonProcessingException {

    ObjectMapper mapper = new ObjectMapper();
    JsonFactory factory = mapper.getFactory();
    JsonNode treeNode = jsonParser.getCodec().readTree(jsonParser);

    Iterator<Map.Entry<String, JsonNode>> fields = treeNode.fields();
    String name = "";

    // collect the tag name
    Map.Entry<String, JsonNode> entry = fields.next();
    name = entry.getKey();

    // now that we have the tag name, parse it as a separate JSON object
    JsonNode node = entry.getValue();

    // get the values from the JSON
    String description = node.get("tag_description").asText();
    String category_id = node.get("tag_category_id").asText();
    String tag_id = node.get("tag_id").asText();

     return new Tag(name, category_id, description, tag_id);
}

---

这不是一个直接的答案，而是一个可能方向的指南，使用Gson

package test;
import java.util.Map;
import com.google.gson.Gson;
public class JsonTest {
    public static void main(final String... args) {
        new JsonTest().run();
    }
    public void run() {
        final Gson gson = new Gson();
        final Map<?, ?> result = gson.fromJson("{" + 
                "    \"Sample\": {" + 
                "        \"tag_description\": \"abc\"," + 
                "        \"tag_category_id\": \"def\"," + 
                "        \"tag_id\": \"ghi\"" + 
                "    }," + 
                "    \"Sample1\": {" + 
                "        \"tag_description\": \"jkl\"," + 
                "        \"tag_category_id\": \"mno\"," + 
                "        \"tag_id\": \"pqr\"" + 
                "    }" + 
                "}", Map.class);
        System.out.println("Map size: " + result.size());
    }
}

封装测试；
导入java.util.Map；
导入com.google.gson.gson；
公共类JsonTest{
公共静态void main（最终字符串…参数）{
新建JsonTest（）.run（）；
}
公开募捐{
最终Gson Gson=新Gson（）；
最终映射结果=gson.fromJson（“{”+
“\”示例\“：{”+
“\”标记描述\“：\”abc\“，“+
“\”标记\类别\ id\“：\”定义\“，“+
“\“标记id\”：\“ghi\”+
"    }," + 
“\”样本1\“：{”+
“\”标记描述\“：\”jkl\“，“+
“\”标记\类别\ id\“：\”mno\“，“+
“\“标记id\”：\“pqr\”+
"    }" + 
“}”，Map.class）；
System.out.println（“映射大小：+result.size（））；
}
}

---

结果大小为2。映射条目是键控的Sample、Sample1，值是包含节点的列表。你可以用调试器看到这个。

如果你正在使用Spring MVC，考虑在引用到<代码> @ RealStests< /C>时显式声明所需的类型，并让框架为你做< /P>的工作。

@PostMapping(value="/store", consumes = APPLICATION_JSON_VALUE)
public void tagJson(@RequestBody Map<String, Tag> json) {
  // Do not mess with ObjectMapper here, Spring will do the thing for you
}

@PostMapping（value=“/store”，consumes=APPLICATION\u JSON\u value）
public void tagJson（@RequestBody-Map-json）{
//不要在这里乱搞ObjectMapper，Spring会帮你做的
}

太棒了，这非常有效！使用它，我可以简单地设置标签上返回的字符串名称，并保存到JPA存储库中。谢谢你！非常感谢您的回复！Spring框架最终承担了很多繁重的工作，但我肯定会看看GsonSpring包含了Jackson JSON处理器，这相当于Gson。

package test;
import java.util.Map;
import com.google.gson.Gson;
public class JsonTest {
    public static void main(final String... args) {
        new JsonTest().run();
    }
    public void run() {
        final Gson gson = new Gson();
        final Map<?, ?> result = gson.fromJson("{" + 
                "    \"Sample\": {" + 
                "        \"tag_description\": \"abc\"," + 
                "        \"tag_category_id\": \"def\"," + 
                "        \"tag_id\": \"ghi\"" + 
                "    }," + 
                "    \"Sample1\": {" + 
                "        \"tag_description\": \"jkl\"," + 
                "        \"tag_category_id\": \"mno\"," + 
                "        \"tag_id\": \"pqr\"" + 
                "    }" + 
                "}", Map.class);
        System.out.println("Map size: " + result.size());
    }
}

@PostMapping(value="/store", consumes = APPLICATION_JSON_VALUE)
public void tagJson(@RequestBody Map<String, Tag> json) {
  // Do not mess with ObjectMapper here, Spring will do the thing for you
}