按特定顺序获取JSON数组的键和值

I'm very new to Java, I'm using it to teach my Lego NXT Robot some ways out of a labyrinth. The algorithm parameters shall be outsourced and loaded in the code, so thats why I use JSON. MY JSON file is pretty simple (lefthand algorthm):

我是Java的新手,我用它来教我的Lego NXT机器人以某种方式摆脱迷宫。算法参数应该外包并加载到代码中,这就是我使用JSON的原因。我的JSON文件很简单(左手algorthm):

{"algorithm": 
    {
      "onGapLeft": "moveLeft",
      "onGapFront": "moveForward",
      "onGapRight": "moveRight",
      "default": "moveBackward"
    }
}

It's very important that this file is read in it's order. I.e. if you change Left and Right the algorithm would become a Right Hand Algorithm. This is the Java Code so far, I hope you understand what I'm trying to do. BTW: I'm using JSON.simple!

这个文件按顺序读取是非常重要的。即如果你改变左和右,算法将成为右手算法。到目前为止,这是Java代码,我希望你能理解我正在做的事情。顺便说一句:我正在使用JSON.simple!

private static void loadAlgorithm() throws InterruptedException {

        JSONParser parser = new JSONParser();


            Object obj = parser.parse(new FileReader("lefthand.json"));             
            JSONObject jsonObject = (JSONObject) obj;
            JSONArray algorithm = (JSONArray) jsonObject.get("algorithm");
            int length = algorithm.size();

        for(int i = 0; i < length; i++)
        {
            switch (algorithm[i].key)
            {
                 case "onGapLeft" :  leftPos = i; break;
                 case "onGapFront": frontPos = i; break;
                 case "onGapRight": rightPos = i; break;
                 default: break;
            }

            switch (algorithm[i].value)
            {
                 case "moveLeft"    : directionAlgorithm[i] = direction.Left;     break;
                 case "moveFront"   : directionAlgorithm[i] = direction.Forward;  break;
                 case "moveRight"   : directionAlgorithm[i] = direction.Right;    break;
                 case "moveBackward": directionAlgorithm[3] = direction.Backward; break;
                 default: break;
            }
        }           
    }

I'll need to know now wether it is possible to get the key string (where I used algorithm[i].key actually) and the same for the value string (algorithm[i].value).

我现在需要知道是否有可能获得密钥字符串(我实际上使用了算法[i] .key)和值字符串(algorithm [i] .value)相同。

Thank you very much for your help!

非常感谢您的帮助!

2 个解决方案

#1

You should probably change your JSON so that it is ordered, something like this:

你可能应该更改你的JSON以便它被订购,如下所示:

{"algorithm": 
    [
        { "key": "onGapLeft", "value" : "moveLeft" },
        { "key": "onGapFront", "value" : "moveForward" },
        { "key": "onGapRight", "value" : "moveRight" },
        { "key": "default", "value" : "moveBackward" }
    ]
}

And then modify your Java accordingly.

然后相应地修改Java。

#2

I am not familiar with JSON , but Since JSONObject is backed by a HashMap, you may be able to get the keys and values into a array in the same order like below,

我不熟悉JSON,但由于JSONObject由HashMap支持,您可以按照下面的相同顺序将键和值放入数组中,

Map<K, V> map = new HashMap<K, V>();
K[] keys = new K[map.size()];
V[] values = new V[map.size()];
int index = 0;
for (Map.Entry<K, V> mapEntry : map.entrySet()) {
    keys[index] = mapEntry.getKey();
    values[index] = mapEntry.getValue();
    index++;
}

#1