如何使用Json.simple解析Java中的JSONArray? [英] How do I parse a JSONArray in Java with Json.simple?

问题描述

我正在尝试读取这样的JSON文件:

I am trying to read a JSON file like this:

{
  "presentationName" : "Here some text",
  "presentationAutor" : "Here some text",
  "presentationSlides" : [
    {
      "title" : "Here some text.",
      "paragraphs" : [
        {
          "value" : "Here some text."
        },
        {
          "value" : "Here some text."
        }
      ]
    },
    {
      "title" : "Here some text.",
      "paragraphs" : [
        {
          "value" : "Here some text.",
          "image" : "Here some text."
        },
        {
          "value" : "Here some text."
        },
        {
          "value" : "Here some text."
        }
      ]
    }
  ]
}

它是用于学校练习的.我选择尝试使用JSON.simple(来自GoogleCode)，但是我对另一个JSON库开放.我听说过杰克逊和格森:它们比JSON.simple好吗?

It's for a school exercise. I chose to try and use JSON.simple (from GoogleCode), but I am open to another JSON library. I heard about Jackson and Gson: Are they better than JSON.simple?

这是我当前的Java代码:

Here is my current Java code:

Object obj = parser.parse(new FileReader( "file.json" ));

JSONObject jsonObject = (JSONObject) obj;

// First I take the global data
String name = (String) jsonObject.get("presentationName");
String autor = (String) jsonObject.get("presentationAutor");
System.out.println("Name: "+name);
System.out.println("Autor: "+autor);

// Now we try to take the data from "presentationSlides" array
JSONArray slideContent = (JSONArray) jsonObject.get("presentationSlides");
Iterator i = slideContent.iterator();

while (i.hasNext()) {
    System.out.println(i.next());
    // Here I try to take the title element from my slide but it doesn't work!
    String title = (String) jsonObject.get("title");
    System.out.println(title);
}

我检查了很多示例(有些在Stack上！)，但从未找到解决问题的方法.

I checked out a lot of examples (some on Stack!) but I never found the solution to my problem.

也许我们无法使用JSON.simple做到这一点?您有什么建议?

Maybe we can't do this with JSON.simple? What do you recommend?

推荐答案

您永远不会为jsonObject分配新值，因此在循环内它仍然引用完整的数据对象.我想您想要类似的东西:

You never assign a new value to jsonObject, so inside the loop it still refers to the full data object. I think you want something like:

JSONObject slide = i.next();
String title = (String)slide.get("title");

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