我们如何使用 gson.JsonObject 在非静态 java 方法/类中创建 Json

Question

Unable to create a JsonObject in a java class, giving syntax error:

Answer 1

you are trying to put code in a invalid body part of the class.

You have to add a method or a constructor to the class example:

public class FileRequestJson {

    JsonObject file = new JsonObject();

    public  FileRequestJson() {
        file.addProperty("", "");
    }

    public JsonObject newMethod(JsonObject newfile){
        newfile.addProperty("", "");
        return newfile;
    }
}

Answer 2

I think you are new to coding. You should write the code within the method. The following code might help you.

    import com.google.gson.JsonObject;

  public class JsonFromGson {

public static void main(String[] args) {
    // TODO Auto-generated method stub
    JsonFromGson  json =new JsonFromGson();
    json.createJson();
}

public void createJson() {

    JsonObject file = new JsonObject();
    file.addProperty("Name", "Jyo");
    file.addProperty("age", 23);
    System.out.print(file);
}

}

Answer 3

Like @Robby Cornelissen said

Code needs to be inside a method or initializer block

Perhaps you meant to have

import com.google.gson.JsonObject;

class FileRequestJson extends JsonObject {
    {
        addProperty("Name", "Jyo");
        addProperty("age", 23);
    }
}

or how I like is...

import org.json.JSONObject;

class AClass {
    public void method() {

        JSONObject fileRequest = new JSONObject() {{
            put("Name", "Jyo");
            put("age", 23);
        }};

        System.out.println(fileRequest.toString(2));
    }
}

Both of these options use non-static block construction which may be considered a little bad practice by some people.