Getting data from JSON
I'm trying to get the values out of this JSON string but I'm having a hard time achieving this.
{"DebugLogId":"1750550","RequestId":"17505503","Result":
{"Code":"","DebugLogId":"1750550","Message":""},
"Suggestions":[
{"Ranking":"1","Score":"60","Title":"This is a test 开发者_如何学Cmessage 1"},
{"Ranking":"2","Score":"60","Title":"This is a test message 2"}
]}
What way would be easiest to access the data in 'Suggestions'? I'm using the GSON module. Ideally I would like to put it all in a HashMap.
Thanks for any help and/or suggestions!
Thanks for any help!
Hope this helps:
App.java:
package sg.java.play_sof_json_6596072;
import com.google.gson.Gson;
public class App {
public static void main(String[] args) {
Gson gson = new Gson();
String jsonString = "{\"DebugLogId\":\"1750550\",\"RequestId\":\"17505503\",\"Result\":{\"Code\":\"\",\"DebugLogId\":\"1750550\",\"Message\":\"\"},\"Suggestions\":[{\"Ranking\":\"1\",\"Score\":\"60\",\"Title\":\"This is a test message 1\"},{\"Ranking\":\"2\",\"Score\":\"60\",\"Title\":\"This is a test message 2\"}]}";
Debug obj = (Debug) gson.fromJson(jsonString, Debug.class);
System.out.println(obj.getSuggestionList().get(1).getTitle());
}
}
Debug.java:
package sg.java.play_sof_json_6596072;
import java.util.List;
import com.google.gson.annotations.SerializedName;
public class Debug {
@SerializedName("DebugLogId")
private String debugLogId;
@SerializedName("RequestId")
private String requestId;
@SerializedName("Result")
private Result result;
@SerializedName("Suggestions")
private List<Suggestion> suggestionList;
/**
* @return the debugLogId
*/
public final String getDebugLogId() {
return this.debugLogId;
}
/**
* @param debugLogId the debugLogId to set
*/
public final void setDebugLogId(String debugLogId) {
this.debugLogId = debugLogId;
}
/**
* @return the requestId
*/
public final String getRequestId() {
return this.requestId;
}
/**
* @param requestId the requestId to set
*/
public final void setRequestId(String requestId) {
this.requestId = requestId;
}
/**
* @return the result
*/
public final Result getResult() {
return this.result;
}
/**
* @param result the result to set
*/
public final void setResult(Result result) {
this.result = result;
}
/**
* @return the suggestionList
*/
public final List<Suggestion> getSuggestionList() {
return this.suggestionList;
}
/**
* @param suggestionList the suggestionList to set
*/
public final void setSuggestionList(List<Suggestion> suggestionList) {
this.suggestionList = suggestionList;
}
}
Result.java:
package sg.java.play_sof_json_6596072;
import com.google.gson.annotations.SerializedName;
public class Result {
@SerializedName("Code")
private String code;
@SerializedName("DebugLogId")
private String debugLogId;
@SerializedName("Message")
private String messahe;
/**
* @return the code
*/
public final String getCode() {
return this.code;
}
/**
* @param code the code to set
*/
public final void setCode(String code) {
this.code = code;
}
/**
* @return the debugLogId
*/
public final String getDebugLogId() {
return this.debugLogId;
}
/**
* @param debugLogId the debugLogId to set
*/
public final void setDebugLogId(String debugLogId) {
this.debugLogId = debugLogId;
}
/**
* @return the messahe
*/
public final String getMessahe() {
return this.messahe;
}
/**
* @param messahe the messahe to set
*/
public final void setMessahe(String messahe) {
this.messahe = messahe;
}
}
Suggestion.java:
package sg.java.play_sof_json_6596072;
import com.google.gson.annotations.SerializedName;
public class Suggestion {
@SerializedName("Ranking")
private String ranking;
@SerializedName("Score")
private String score;
@SerializedName("Title")
private String title;
/**
* @return the ranking
*/
public final String getRanking() {
return this.ranking;
}
/**
* @param ranking the ranking to set
*/
public final void setRanking(String ranking) {
this.ranking = ranking;
}
/**
* @return the score
*/
public final String getScore() {
return this.score;
}
/**
* @param score the score to set
*/
public final void setScore(String score) {
this.score = score;
}
/**
* @return the title
*/
public final String getTitle() {
return this.title;
}
/**
* @param title the title to set
*/
public final void setTitle(String title) {
this.title = title;
}
}
I'm recommend you to use flexjson library http://flexjson.sourceforge.net/ IMHO, it more simple and usable library. I has used GSON first time, but then switched all my projects to flexjson instead of GSON.
Using the standard json classes in android:
JSONObject o = new JSONObject("your string");
JSONArray a = o.getJSONArray("Suggestions");
int i = 0;
while ( i < a.length())
{
o = a.getJSONObject(i);
//do something with o, like o.getString("Title") ...
++i;
}
Ideally I would like to put it all in a HashMap.
If you can switch libraries, Jackson can achieve that with just one line of code.
Map map = new ObjectMapper().readValue(json, Map.class);
This would deserialize any JSON object into a HashMap
, composed of just Java SE components. I haven't yet seen another Java-to/from-JSON library that can do that.
The same can be accomplished with Gson, but it requires a few more lines of code. Here's one such solution.
JsonElement je = new JsonParser().parse(json);
JsonObject jo = je.getAsJsonObject();
Map<String, Object> map = createMapFromJsonObject(jo);
// ...
static Map<String, Object> createMapFromJsonObject(
JsonObject jo)
{
Map<String, Object> map = new HashMap<String, Object>();
for (Entry<String, JsonElement> entry : jo.entrySet())
{
String key = entry.getKey();
JsonElement value = entry.getValue();
map.put(key, getValueFromJsonElement(value));
}
return map;
}
static Object getValueFromJsonElement(JsonElement je)
{
if (je.isJsonObject())
{
return createMapFromJsonObject(je.getAsJsonObject());
}
else if (je.isJsonArray())
{
JsonArray array = je.getAsJsonArray();
List<Object> list = new ArrayList<Object>(array.size());
for (JsonElement element : array)
{
list.add(getValueFromJsonElement(element));
}
return list;
}
else if (je.isJsonNull())
{
return null;
}
else // must be primitive
{
JsonPrimitive p = je.getAsJsonPrimitive();
if (p.isBoolean()) return p.getAsBoolean();
if (p.isString()) return p.getAsString();
// else p is number, but don't know what kind
String s = p.getAsString();
try
{
return new BigInteger(s);
}
catch (NumberFormatException e)
{
// must be a decimal
return new BigDecimal(s);
}
}
}
(I copied this code from my blog post at http://programmerbruce.blogspot.com/2011/06/gson-v-jackson.html.)
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