Reputation: 167
I would like to parse data from JSON which is String type. I am using Google Gson. I'm wondering how can I get "OriginalTerm" and "FirstTranslation" information of this Json String:
{
"term0" : {
"PrincipalTranslations" : {
"0" :{
"OriginalTerm" : { "term" : "cat", "POS" : "n", "sense" : "domestic animal", "usage" : ""},
"FirstTranslation" : {"term" : "gato", "POS" : "nm", "sense" : " "}, "Note" : ""},
"1" :{
"OriginalTerm" : { "term" : "cat", "POS" : "n", "sense" : "member of cat family", "usage" : ""},
"FirstTranslation" : {"term" : "felino", "POS" : "nm", "sense" : "familia de animales"}, "Note" : ""}},
"AdditionalTranslations" : {
"0" :{
"OriginalTerm" : { "term" : "cat", "POS" : "n", "sense" : "guy", "usage" : "slang"},
"FirstTranslation" : {"term" : "tío, tipo, chaval", "POS" : "nm", "sense" : "coloq"},
"SecondTranslation" : {"term" : "vato", "POS" : "", "sense" : "Mex"}, "Note" : ""},
"original" : {
"Compounds" : {
"0" :{
"OriginalTerm" : { "term" : "alley cat", "POS" : "n", "sense" : "stray cat", "usage" : ""},
"FirstTranslation" : {"term" : "gato callejero", "POS" : "nm", "sense" : ""}, "Note" : ""},
"Lines" : "End Reached", "END" : true
}
I tried following these information but I can't solve it:
http://albertattard.blogspot.com.es/2009/06/practical-example-of-gson.html
JSON parsing using Gson for Java
I tried to serialized using GSON using POJO but I can't find the right structure, I tried using JsonObject too, jumping through object keys like "term0","PrincipalTranslations" but I have some trouble when I've multiple results for the same key, for example:
"0" :{
"OriginalTerm"....
"FirstTranslation"...
"1" :{
"OriginalTerm"....
"FirstTranslation"...
}
Thank you for advance.
Upvotes: 2
Views: 9403
Reputation: 6934
Parsing a JSON with Gson can be done using a POJO that maps one-to-one your JSON text with your object. But, since you need only part of the JSON string, you can take advantage of JsonParser
object that allows you to get a portion only of your JSON.
So you can get PrincipalTranslation
part and then apply the POJO strategy keeping in mind that you have at least two structures: your Term
and a composition of two Term
s and a note (that I called Item
).
Keep in mind that POJO I write are not following Java naming convention, so you can add an annotation to use a different member variable name.
Here's a code you can paste and run in you IDE to try.
package stackoverflow.questions;
import java.lang.reflect.Type;
import java.util.*;
import com.google.gson.*;
import com.google.gson.reflect.TypeToken;
public class Q20337652 {
public static class Term {
String term;
String POS;
String sense;
String usage;
@Override
public String toString() {
return "Term [term=" + term + ", POS=" + POS + ", sense=" + sense + ", usage=" + usage + "]";
}
}
public static class Item {
Term OriginalTerm;
Term FirstTranslation;
String Note;
@Override
public String toString() {
return "Item [OriginalTerm=" + OriginalTerm + ", FirstTranslation=" + FirstTranslation + ", Note=" + Note + "]";
}
}
public static void main(String[] args){
String json =
" { "+
" "+
" \"term0\" : { "+
" \"PrincipalTranslations\" : { "+
" \"0\" :{ "+
" \"OriginalTerm\" : { \"term\" : \"cat\", \"POS\" : \"n\", \"sense\" : \"domestic animal\", \"usage\" : \"\"}, "+
" \"FirstTranslation\" : {\"term\" : \"gato\", \"POS\" : \"nm\", \"sense\" : \" \"}, \"Note\" : \"\"}, "+
" \"1\" :{ "+
" \"OriginalTerm\" : { \"term\" : \"cat\", \"POS\" : \"n\", \"sense\" : \"member of cat family\", \"usage\" : \"\"}, "+
" \"FirstTranslation\" : {\"term\" : \"felino\", \"POS\" : \"nm\", \"sense\" : \"familia de animales\"}, \"Note\" : \"\"}},"+
" \"AdditionalTranslations\" : { "+
" \"0\" :{ "+
" \"OriginalTerm\" : { \"term\" : \"cat\", \"POS\" : \"n\", \"sense\" : \"guy\", \"usage\" : \"slang\"}, "+
" \"FirstTranslation\" : {\"term\" : \"tío, tipo, chaval\", \"POS\" : \"nm\", \"sense\" : \"coloq\"}, "+
" \"SecondTranslation\" : {\"term\" : \"vato\", \"POS\" : \"\", \"sense\" : \"Mex\"}, \"Note\" : \"\"}, "+
" "+
" \"original\" : { "+
" \"Compounds\" : { "+
" \"0\" :{ "+
" \"OriginalTerm\" : { \"term\" : \"alley cat\", \"POS\" : \"n\", \"sense\" : \"stray cat\", \"usage\" : \"\"}, "+
" \"FirstTranslation\" : {\"term\" : \"gato callejero\", \"POS\" : \"nm\", \"sense\" : \"\"}, \"Note\" : \"\"}, "+
" \"Lines\" : \"End Reached\", \"END\" : true "+
" "+
" } "+
" } }}} ";
JsonParser jp = new JsonParser();
JsonElement je = jp.parse(json);
JsonElement je2 = je.getAsJsonObject().get("term0");
JsonElement je3 = je2.getAsJsonObject().get("PrincipalTranslations");
Type mapType = new TypeToken<Map<String, Item>>() {}.getType();
Map<String, Item> principalTranslation = new Gson().fromJson(je3, mapType);
System.out.println(principalTranslation);
}
}
And this is my execution:
{0=Item [OriginalTerm=Term [term=cat, POS=n, sense=domestic animal, usage=], FirstTranslation=Term [term=gato, POS=nm, sense= , usage=null], Note=],
1=Item [OriginalTerm=Term [term=cat, POS=n, sense=member of cat family, usage=], FirstTranslation=Term [term=felino, POS=nm, sense=familia de animales, usage=null], Note=]}
Upvotes: 3
Reputation: 771
I think this could help: http://www.newthinktank.com/2013/07/android-development-15/
It's a video tutorial explaining the how to use json. Not through GSON though, but I think you need a base on how JSON works before getting involved in GSON (it's rather complicated)
Upvotes: 2