So one of the big changes we got now, is the possibility of having our own custom *.json files with all the static data we need without having to resort creating massive Arrays/ArrayLists/Hash...etc.
So how do they work?First of all, you should check the website
www.json.org it gives you a very detailed explanation of what
data and
format can you expect from a *.json file.
There are 2 formats that can be inside each other, a JSONObject that can have a JSONArray(s), JSONObject(s) or data inside (or even all mixed in), or a JSONArray that can have more JSONArray(s) or more JSONObject(s) (or even both mixed in). Knowing the format is extremely important to extract certain type of data in the JSONObject.
How you do know whats an JSONArray and whats a JSONObject?Heres a example (battle_objectives.json):{ "nav_buoy":
{ "name":"Nav Buoy",
"icon":"graphics/warroom/objective_nav_buoy.png",
"sprite":"graphics/ships/nav_buoy.png",
"spriteScale":1.5,
"captureTime":10,
"effectClass":"com.fs.starfarer.api.impl.combat.NavBuoyEffect",
}, "sensor_array":
{ "name":"Sensor Array",
"icon":"graphics/warroom/objective_sensor_array.png",
"sprite":"graphics/ships/sensor_array.png",
"spriteScale":1,
"captureTime":10,
"effectClass":"com.fs.starfarer.api.impl.combat.SensorArrayEffect",
}, "comm_relay":
{ "name":"Comm Relay",
"icon":"graphics/warroom/objective_comm_relay.png",
"sprite":"graphics/ships/com_relay.png",
"spriteScale":1,
"captureTime":10,
"effectClass":"com.fs.starfarer.api.impl.combat.CommRelayEffect",
},}In
red and
orange,
inside the {} are JSONObjects, but you can have more
JSONObjects inside a
JSONObject.
The main
JSONObject (the one thats got everything inside the orange {}'s) has 3
JSONObjects. These have (can also not have) identifiers as a text in the green ""'s, if you only want a specific
JSONObject, you get the id in the
"", if you want a specific data value inside the
JSONObject, you use the id in the ""'s (not the green one).
JSONArray starts with []'s instead, and are just like what you expect on a Array,
Heres a small example (sounds.json):
{ "music":
{ # "source" can also be a directory
"music_campaign":
[ {"file":"StianStark-Starfarer-Exploration_Alpha.ogg","source":"sounds/music/music.bin"
} ], "music_title":
[ {"file":"StianStark-Starfarer-Exploration_Alpha.ogg","source":"sounds/music/music.bin"
} ], "music_combat":
[ {"file":"battle_ambience_01_v02_loudest.ogg","source":"sounds/music/music.bin"
} ], }}In this particular case we got a
JSONObject thats got several (if i pasted all the sounds.json, not true on this piece of json)
JSONObjects and each of these got one or more
JSONArray(s) and finally we got
JSONObject inside each
JSONArray with no identifier. Just like on the first example you got the identifiers for each
JSONObject and now on
JSONArray as well.
Heres a cool way to understand the format of this example:JSONObject{
}
Now how do i use it on the game itself?
To get a json from you game folder you need something like this:
JSONArray jarray = new JSONArray(JSON_FILE_URL);
or
JSONObject jobject = new JSONObject(JSON_FILE_URL);
It will ask to set up a Try{}Catch{} since your asking for a file that may or may not exist in that URL/Directory
Once done, depending on how the json file format composition is, lets use the second example as the file we want the data:
try {
JSONObject jobject = new JSONObject(JSON_FILE_URL);
} catch (JSONException ex) {
//set the default log message here including the ex (Exception)
Logger.getLogger(SectorGen.class.getName()).log(Level.SEVERE, null, ex);
}
if(jobject != null)
{
for(int i = 0; i < jobject.length();i++)
{
//grab this jsonobject in the list
JSONObject jobj = jobject.getJSONObject(i);
for(int x = 0;x < jobj.length();x++)
{
JSONArray jarray = jobj.getJSONArray(x);
for(int a = 0; a < jarray.length();a++)
{
JSONObject jlastobj = jarray.getJSONObject(a);
for(int l = 0; l < jlastobj.length();l++)
{
//get this value on this line into stringdata arraylist
stringdata.add(jlastobj.getString("file"));
stringdata.add(jlastobj.getString("source"));
}
}
}
}
This should save all the strings inside the "file":"" and "source":"".
All you do is Open the next "container" until you reach what you want.
You can also get a specific data from a JSONObject/Array with a certain ID.
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Topic: How To: use JSONArray(s)/JSONObject(s) from custom *.json files. (Read 2618 times)