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javajsonrestlet

ArrayList<Object> JSON


I am trying to return JSON data with my restlet. I can return a single item's JSON with..

import org.json.JSONObject;

Site aSite = new Site().getSite();   
JSONObject aSiteJson = new JSONObject(aSite);
return aSiteJson.toString();

Returns: {"name":"qwerty","url":"www.qwerty.com"}

How do i return JSON for ArrayList Object

ArrayList<Site> allSites = new SitesCollection().getAllSites();   
JSONObject allSitesJson = new JSONObject(allSites);
return allSitesJson.toString();

Returns: {"empty":false}

ArrayList<Site> allSites = new SitesCollection().getAllSites();   
JSONArray allSitesJson = new JSONArray(allSites);
return allSitesJson.toString();

Returns: ["com.sample.Site@4a7140","com.sample.Site@1512c2e","com.sample.Site@2bba21","com.sample.Site@c8d0b7"]

Here is my Site class

public class Site {
private String name;
private String url;

public String getName() {
    return name;
}
public void setName(String name) {
    this.name = name;
}
public String getUrl() {
    return url;
}
public void setUrl(String url) {
    this.url = url;
}

public Site(String name, String url) {
    super();
    this.name = name;
    this.url = url;
}       

}

Thanks


Solution

  • You coud use Gson library, that handles lists properly, instead.


    Usage example:

    class BagOfPrimitives {
        private int value1;
        private String value2;
        private transient int value3;
        public BagOfPrimitives(int value1, String value2, int value3) {
            this.value1 = value1;
            this.value2 = value2;
            this.value3 = value3;
        }
    }
    
    BagOfPrimitives obj1 = new BagOfPrimitives(1, "abc", 3);
    BagOfPrimitives obj2 = new BagOfPrimitives(32, "gawk", 500);
    List<BagOfPrimitives> list = Arrays.asList(obj1, obj2);
    Gson gson = new Gson();
    String json = gson.toJson(list);  
    // Now json is [{"value1":1,"value2":"abc"},{"value1":32,"value2":"gawk"}]