Ruben’s blog

I´ve been trying to use XStream to generate JSON to be consumed by Dojo. But I can´t find the way to generate the right JSON from XStream, it keeps adding extraneous {} around. I even tried this but no luck . For example I want to generate this JSON output (taken from Dojo FilteringSelect example) :

{identifier:"abbreviation",
items: [
    {name:"Alaska", label:"Alaska",abbreviation:"AK"},
    {name:"Wyoming", label:"Wyoming",abbreviation:"WY"}
]}

My attempt usign XStream:

package com.rubenlaguna.json;

import java.util.ArrayList;
import java.util.Collection;

import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.io.json.JettisonMappedXmlDriver;

class ItemCollection {
    public String identifier;
    public Collection<Item> items = new ArrayList<Item>();

    public ItemCollection(String identifier) {
        this.identifier = identifier;
    }

    public boolean add(Item arg0) {
        return items.add(arg0);
    }

}

class Item {
    public String name;
    public String label;
    public String abbreviation;

    public Item(String name, String label, String abbreviation) {
        this.name = name;
        this.label = label;
        this.abbreviation = abbreviation;
    }

}

public class WriteXStreamDojoTest {

    public static void main(String[] args) {
        ItemCollection itemCollection = new ItemCollection("abbreviation");
        itemCollection.add(new Item("Alaska","Alaska","AK"));
        itemCollection.add(new Item("Wyoming","Wyoming","WY"));
        
        XStream xstream = new XStream(new JettisonMappedXmlDriver());
        String erroneousJsonStr = xstream.toXML(itemCollection);
        System.out.println(erroneousJsonStr);

    }

}

resulted in the following JSON Output (i added some space and breaklines for readability):

{"com.rubenlaguna.json.ItemCollection":
       {"identifier":"abbreviation",
         "items":{ "@class":"list",
                      "com.rubenlaguna.json.Item":[  
                         {"name":"Alaska","label":"Alaska","abbreviation":"AK"},
                         {"name":"Wyoming","label":"Wyoming","abbreviation":"WY"}
                       ]
                   }
      }
}

I couldn´t figure out how to get XStream to output the desired JSON. The main issue is that I couldn´t make “items” a simple JSON array, it always end up as an object with an array in it. So I decided to give out a try to FLEXJSON. I really found much easier to control the output with this tool. I guess that XStream is more focused on serialization/deserialization and doesn´t allow customization without relaying in custom converters (I didn´t walk that road, too much work). Here is the example source code usign FLEXJSON:

package com.rubenlaguna.json.flexjson;

import flexjson.JSONSerializer;

public class WriteFlexjsonDojoTest {

    public static void main(String[] args) {
        ItemCollection itemCollection = new ItemCollection("abbreviation");
        itemCollection.add(new Item("Alaska", "Alaska", "AK"));
        itemCollection.add(new Item("Wyoming", "Wyoming", "WY"));

        JSONSerializer serializer = new JSONSerializer().include("items").exclude("*.class");
        String correctJsonStr = serializer.serialize(itemCollection);
        System.out.println(correctJsonStr);

    }

}

that yields the following correct result:

{"identifier":"abbreviation",
  "items":[ {"name":"Alaska","label":"Alaska","abbreviation":"AK"},
              {"name":"Wyoming","label":"Wyoming","abbreviation":"WY"}
            ]}

Continuing with my previous post 1 , 2 …. I wrote a little script that I run every day via Windows Scheduled tasks. The script adjust the volume and EQ setting of all the podcasts and audiobooks everyday to update the just downloaded podcast. I find hard to listen to podcast and audiobook at the gym (that’s were I hear the podcast/audiobok) at the standard volume so I like to adjust the volume +100% and change the EQ setting to “Spoken word”.

Save the file adjustvolume.js and make sure that file extension is handled by wscript.exe. The file association windows should look like this

Now in Control Panel -> Scheduled Tasks you can set that script to execute every day to maintain your podcasts and audiobook with the correct settings