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POHow to write a JSONObject to a file, which has JSONArray inside it, in Java?
 

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  1. POHow to write a JSONObject to a file, which has JSONArray inside it, in Java?
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    <p>I have JSON file, that I need to read, edit and write out again.</p> <p>Reading works fine, I struggle with the write part of the JSON Array in my data.</p> <p>I use <a href="https://github.com/fangyidong/json-simple" rel="nofollow">JSON.simple</a> library to work with JSON in Java.</p> <p>The file looks like this:</p> <pre><code>{ "maxUsers":100, "maxTextLength":2000, "maxFileSize":2000, "services": [ { "serviceName":"Яндекc", "className":"YandexConnector.class", "isEnabled":true }, { "serviceName":"Google", "className":"GoogleConnector.class", "isEnabled":false } ] } </code></pre> <p>When I try to write JSON-data (variable <code>obj</code>) to file, the <code>services</code> array is broken. My writing code:</p> <pre><code>JSONObject obj = new JSONObject(); obj.put("maxUsers", this.getMaxUsers()); obj.put("maxTextLength", this.getMaxTextLength()); obj.put("maxFileSize", this.getMaxFileSize()); JSONArray servicesJSON = new JSONArray(); ArrayList&lt;Service&gt; servicesArray = this.getServices(); for(int i=0; i&lt; servicesArray.size(); i++) { servicesJSON.add(servicesArray.get(i)); } obj.put("services", servicesJSON); FileWriter file = new FileWriter(filename); obj.writeJSONString(file); file.flush(); file.close(); </code></pre> <p>This outputs:</p> <pre><code>{ "services": [ translator.settings.Service@121c5df, translator.settings.Service@45f4ae ], "maxTextLength":2000, "maxUsers":100, "maxFileSize":2000 } </code></pre> <p>How can I write the JSON data correctly to a file, if I have it in a JSONArray like <code>services</code> ? </p> <hr> <p>The code, where I read the JSON data from the file (that works fine):</p> <pre><code>JSONParser parser = new JSONParser(); Object obj = parser.parse(new FileReader(filename)); JSONObject jsonObject = (JSONObject) obj; setMaxUsers((Long) jsonObject.get("maxUsers")); setMaxTextLength((Long) jsonObject.get("maxTextLength")); setMaxFileSize((Long) jsonObject.get("maxFileSize")); // get all list of services JSONArray serv = (JSONArray) jsonObject.get("services"); for (int i = 0; i &lt; serv.size(); i++) { JSONObject service = (JSONObject) serv.get(i); Service servec = new Service(); servec.setServiceName((String) service.get("serviceName")); servec.setClassName((String) service.get("className")); servec.setIsEnabled((Boolean) service.get("isEnabled")); services.add(i, servec); } </code></pre> <p>The editing part is not yet written, so I call the writing part directly after the reading.</p> <hr>
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    1. PTQuestion
    1. USAngelo Fuchs
    1. USalena_fox_spb
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      1. POHow to write a JSONObject to a file, which has JSONArray inside it, in Java?
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      1. VTUpMod
    1. COThere is definitely a problem with the edit part, which you're not showing. You store instances of Service class in your JSON array, instead of storing JSONObject instances.
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      1. POHow to write a JSONObject to a file, which has JSONArray inside it, in Java?
      1. USJB Nizet
    2. COShow us how you create your JSON-data `obj`.
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      1. POHow to write a JSONObject to a file, which has JSONArray inside it, in Java?
      1. USSotirios Delimanolis
    3. CO@SotiriosDelimanolis , I add part with code . can you look at it?
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      1. POHow to write a JSONObject to a file, which has JSONArray inside it, in Java?
      1. USalena_fox_spb
 

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