I have a json respons as followed using java. One of the field is a key:value pair of an array. And I have no idea how to get that as an array - java

{
"items": [
{
"volumeInfo": {
"industryIdentifiers": [
{
"type": "ISBN_10",
"identifier": "0080509576"
},
{
"type": "ISBN_13",
"identifier": "9780080509570"
}
]
}
}
]
}
In the above json, I need to extract industryIdentifiers' identifier value without losing any digit.
I have tried using JSONArray but it eats up some of the digits
jsonObj.getJSONObject("items")
.getJSONObject("volumeInfo").getJSONArray("industryIdentifiers")
.getString(0);
Can anyone help me out?

Get the json array first and then iterate through it to parse.
Use org.json
import org.json.JSONArray;
import org.json.JSONObject;
JSONArray array = jsonObj.getJSONArray("items").getJSONObject(0).getJSONObject("volumeInfo")
.getJSONArray("industryIdentifiers");
for (int i = 0; i < array.length(); i++) {
String type = array.getJSONObject(i).getString("type");
String identifier = array.getJSONObject(i).getString("identifier");
System.out.println(type + " identifier : " + identifier);
}
Output on Java 9
ISBN_10 identifier : 0080509576
ISBN_13 identifier : 9780080509570

Related

Parsing Chrome Bookmarks Json file : Java

Currently I am using netbeans IDE. I tried using other solution, but to no luck so far.
Problem is, i am facing errors when trying to read the Json file from google Chrome bookmarks file (C:\Users\Admin\AppData\Local\Google\Chrome\User Data\Default\Bookmarks)
p/s: although there is no file type written in the name of Bookmarks, its content have been known as JSON
This is the what inside the Bookmarks.json:
{
"checksum": "20fdfad51db6d3199f8a09c3220dd93b",
"roots": {
"bookmark_bar": {
"children": [ {
"date_added": "13124893413824227",
"id": "6",
"name": "YouTube",
"type": "url",
"url": "https://www.youtube.com/"
}, {
"date_added": "13124893435163243",
"id": "7",
"name": "Welcome to Facebook",
"type": "url",
"url": "https://www.facebook.com/"
} ],
"date_added": "13124893381424539",
"date_modified": "13124893435163243",
"id": "1",
"name": "Bookmarks bar",
"type": "folder"
},
"other": {
"children": [ ],
"date_added": "13124893381424547",
"date_modified": "0",
"id": "2",
"name": "Other bookmarks",
"type": "folder"
},
"synced": {
"children": [ ],
"date_added": "13124893381424550",
"date_modified": "0",
"id": "3",
"name": "Mobile bookmarks",
"type": "folder"
}
},
"version": 1
}
And here is my code (JsonParser.java):
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.Iterator;
import org.json.simple.JSONArray;
import org.json.simple.JSONObject;
import org.json.simple.parser.JSONParser;
import org.json.simple.parser.ParseException;
public class JsonParser{
private static String jsonFile = "C:\\Users\\Admin\\AppData\\Local\\Google\\Chrome\\User Data\\Default\\Bookmarks";
public static void main (String[] args) {
try {
FileReader reader = new FileReader (jsonFile); //access the file
JSONObject jsonObject = (JSONObject) new JSONParser().parse(reader);
String c =(String) jsonObject.get("checksum"); //place
// String r =(String) jsonObject.get("roots"); //place
// String r =(String) jsonObject.get("children"); //place
System.out.println("check: " + c);
//System.out.println("roots: " + r);
JSONArray lang = (JSONArray) jsonObject.get("roots");
for (int i=0; i<lang.size(); i++) {
System.out.println ("Url Name : " + lang.get(i)+"\n");
} //data in the array
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (ParseException e) {
e.printStackTrace();
}
}
}
For some reason when I run the code these are the errors I got:
check: 4d55f8a0888f7dd918a702eda2821ccd
Exception in thread "main" java.lang.ClassCastException: org.json.simple.JSONObject cannot be cast to org.json.simple.JSONArray
at JsonParser.main(JsonParser.java:28)
C:\Users\Admin\Documents\NetBeansProjects\Keep-It\nbproject\build-impl.xml:1051: The following error occurred while executing this line:
C:\Users\Admin\Documents\NetBeansProjects\Keep-It\nbproject\build-impl.xml:805: Java returned: 1
BUILD FAILED (total time: 2 seconds)
As you can see, only checksum succeed in being read, but the roots failed and gave out these errors.
You should also notice that there are some codes I put as comments, those are things i tried but still got the errors.
I hope anyone can help me to get these things working.
Thank you very much for helping
Issue is , you cannot cast object to array like (JSONArray) jsonObject.get("roots"); you have to follow the structure so parse according to object and array as shown below
JSONObject jsonObject = (JSONObject) new JSONParser().parse(reader);
String checksum =jsonObject.optString("checksum");
// get root object
JSONObject root = jsonObject.getJSONObject("roots");
// get root bookmarks object from root
JSONObject bookmarks = root.getJSONObject("bookmark_bar");
// get root children array from bookmarks
JSONArray childrens = bookmarks.getJSONArray("children");
JSONObject temp ;
for (int i=0; i<childrens.size(); i++) {
// get object using index from childrens array
temp = childrens.getJSONObject(i);
// get url
String url = temp.optString("url");
}
as your structure follow
JObject => root
root JSONObject has : bookmark_bar JSONObject
bookmark_bar JSONObject has : children JSONArray
children JSONArray has JSONObject which further has String: url
roots is not a JSONArray but a JSONObject.
So what you have to do is
JSONObject lang = jsonObject.get("roots");
and then you have too loop through all keys in the object which should be:
bookmark_bar
other
synced
It seems to me like "roots" is not an array, but an object when looking at the JSON. "children" under "bookmark_bar" is an array however

Getting a specific value inside a JSON array (Java)

I'm trying to get the value of a specific attribute in a JSON file but instead I get a row content of the array.
For example that's my JSON file:
{
"head": {
"vars": [ "type1" , "pred" , "type2" ]
} ,
"results": {
"bindings": [
{
"type1": { "type": "Collection" } ,
"type2": { "type": "has" } ,
"type3": { "type": "contributor" }
} ,
{
"type1": { "type": "Collection2" } ,
"type2": { "type": "has2" } ,
"type3": { "type": "contributor2" }
}
]
}
}
I want to get only the values of attribute "type3"
But my following code gets me all of them.
JSONObject obj = new JSONObject(json);
JSONObject results = obj.getJSONObject("results");
JSONArray bindings = results.getJSONArray("bindings");
for (int i=0; i<bindings.length(); i++)
{
JSONObject x = bindings.getJSONObject(i);
x.getJSONObject("type3");
}
I tried several approaches but it seems I'm doing it wrong.
I only want to get this : { "type": "contributor" }
Then get that value (roughly) like so
bindings.getJSONObject(0).getJSONObject("type3")
you can use JsonPath.read to get all Type3 values as list.
List value = JsonPath.read(bindings, "..type3");

Extracting data from JSON array

I know its an array, but I am completely new to JSON and need help comprehending how this is structured, here is my attempt at extracting data:
String JSonString = readURL("//my URL is here");
JSONArray s = JSONArray.fromObject(JSonString);
JSONObject Data =(JSONObject)(s.getJSONObject(0));
System.out.println(Data.get("name"));
My JSON data that I have goes like this :
{
"sports": [
{
"name": "basketball",
"id": 40,
"uid": "s:40",
"leagues": [
{
"name": "National Basketball Assoc.",
"abbreviation": "nba",
"id": 46,
"uid": "s:40~l:46",
"groupId": 7,
"shortName": "NBA",
"athletes": []
}
]
}
],
"resultsOffset": 10,
"resultsLimit": 10,
"resultsCount": 1,
"timestamp": "2013-11-18T03:15:43Z",
"status": "success"
}
I dont really have a strong grasp of this stuff so all the help is appreciated.
Here is the idea :
JSONObject root = new JSONObject(yourJsonString);
JSONArray sportsArray = root.getJSONArray("sport");
// now get the first element:
JSONObject firstSport = sportsArray.getJSONObject(0);
// and so on
String name = firstSport.getString("name"); // basketball
int id = firstSport.getInt("id"); // 40
JSONArray leaguesArray = firstSport.getJSONArray("leagues");
// and so on, you can process leaguesArrays similarily
It should work (feel free to complain about compile errors if there are any)
Your JSON data is an object (it starts with a curly brace). In the next inner layer, there is a single array (at key "sports"):
String jsonString = readURL("//my URL is here");
JSONObject result = JSONObject(jsonString);
JSONArray sports = result.getJSONArray("sports");
JSONObject sport = sport.getJSONObject(0);
System.out.println(sport.getString("name"));
I might have used another JSON library than you.
JSON means JavaScript Object Notation.
Objects in javascripts are just containers and can be represented by key-value pairs. Please find below notations to understand about json.
Represent objects in json: E.g. Student
{"name" : "Robin", "rollnumber" : "1"}
Represent array in json : E.g. Array of students
[{"name" : "Robin", "rollnumber" : "1"}, {"name" : "Mark", "rollnumber" : "2"}]
You can understand more on JSON from diagrams on this link http://www.json.org/fatfree.html
There are various ways available to to convert JSON to javaobject and javaobject to JSON : One of them is http://wiki.fasterxml.com/JacksonInFiveMinutes
Adding detailed code here along with the imports .
If this helps.
import org.json.JSONException;
import org.json.JSONObject;
public class extractingJSON {
public static void main(String[] args) throws JSONException {
// TODO Auto-generated method stub
String jsonStr = "{\"name\":\"SK\",\"arr\":{\"a\":\"1\",\"b\":\"2\"},\"arrArray\":[{\"a\":\"1\",\"b\":\"2\"}]}";
JSONObject jsonObj = new JSONObject(jsonStr);
String name = jsonObj.getString("name");
System.out.println(name);
String first = jsonObj.getJSONObject("arr").getString("a");
System.out.println(first);
first = jsonObj.getJSONArray("arrArray").getJSONObject(0).getString("a");
System.out.println(first);
}
}

jsonArray.length() not given the right number of array element

I am using org.json parser.
I am getting a json array using jsonObject.getJSONArray(key).
The problem is the jsonArray.length() is returning me 1 and my json array have 2 elements, what am I doing wrong?
String key= "contextResponses";
JSONObject jsonObject = new JSONObject(jsonInput);
Object value = jsonObject.get("contextResponses");
if (value instanceof JSONArray){
JSONArray jsonArray = (JSONArray) jsonObject.getJSONArray(key);
System.out.println("array length is: "+jsonArray.length());/*the result is 1! */
}
Here is my json:
{
"contextResponses" : [
{
"contextElement" : {
"type" : "ENTITY",
"isPattern" : "false",
"id" : "ENTITY3",
"attributes" : [
{
"name" : "ATTR1",
"type" : "float",
"value" : ""
}
]
},
"statusCode" : {
"code" : "200",
"reasonPhrase" : "OK"
}
}
]
}
The result is perfectly normal, since the JSONArray contains only one JSONObject. To get the length of the JSONObject you're looking for, use this:
// Get the number of keys stored within the first JSONObject of this JSONArray
jsonArray.getJSONObject(0).length();
//----------------------------
{
"contextResponses" : [
// The first & only JSONObject of this JSONArray
{
// 2 JSONObjects
"contextElement" : {
// 1
},
"statusCode" : {
// 2
}
}
]
}
Your array contains exactly one object therefore the length is correct:
"contextResponses" : [
{
... content of the object ...
}
]

Parsing JSON File Java [duplicate]

This question already has an answer here:
How to parse JSON in Java
28 answers
I want to parse a JSON file in java and get the following values from the file mentioned below:
{
"status": "OK",
"origin_addresses": [ "Vancouver, BC, Canada", "Seattle, État de Washington, États-Unis" ],
"destination_addresses": [ "San Francisco, Californie, États-Unis", "Victoria, BC, Canada" ],
"rows": [ {
"elements": [ {
"status": "OK",
"duration": {
"value": 340110,
"text": "3 jours 22 heures"
},
"distance": {
"value": 1734542,
"text": "1 735 km"
}
}, {
"status": "OK",
"duration": {
"value": 24487,
"text": "6 heures 48 minutes"
},
"distance": {
"value": 129324,
"text": "129 km"
}
} ]
}, {
"elements": [ {
"status": "OK",
"duration": {
"value": 288834,
"text": "3 jours 8 heures"
},
"distance": {
"value": 1489604,
"text": "1 490 km"
}
}, {
"status": "OK",
"duration": {
"value": 14388,
"text": "4 heures 0 minutes"
},
"distance": {
"value": 135822,
"text": "136 km"
}
} ]
} ]
}
From every element, i want to get the value field of both distance and duration. How do i do this?
Using the json.org reference implementation (org.json homepage, Download here). The code is a bit messy but I think it does what you are asking for. You can take alot of shortcuts by not creating all this objects but to access them directly. The reason that I do it this way is an attempt to make it easier to follow whats happening.
package com.mypackage;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
public class Main {
public static void main(String[] args) {
String jsonStr = "{\"status\": \"OK\",\"origin_addresses\": [ \"Vancouver, BC, Canada\", \"Seattle, État de Washington, États-Unis\" ],\"destination_addresses\": [ \"San Francisco, Californie, États-Unis\", \"Victoria, BC, Canada\" ],\"rows\": [ {\"elements\": [ {\"status\": \"OK\",\"duration\": {\"value\": 340110,\"text\": \"3 jours 22 heures\"},\"distance\": {\"value\": 1734542,\"text\": \"1 735 km\"}}, {\"status\": \"OK\",\"duration\": {\"value\": 24487,\"text\": \"6 heures 48 minutes\"},\"distance\": {\"value\": 129324,\"text\": \"129 km\"}} ]}, {\"elements\": [ {\"status\": \"OK\",\"duration\": {\"value\": 288834,\"text\": \"3 jours 8 heures\"},\"distance\": {\"value\": 1489604,\"text\": \"1 490 km\"}}, {\"status\": \"OK\",\"duration\": {\"value\": 14388,\"text\": \"4 heures 0 minutes\"},\"distance\": {\"value\": 135822,\"text\": \"136 km\"}} ]} ]}";
try {
JSONObject rootObject = new JSONObject(jsonStr); // Parse the JSON to a JSONObject
JSONArray rows = rootObject.getJSONArray("rows"); // Get all JSONArray rows
for(int i=0; i < rows.length(); i++) { // Loop over each each row
JSONObject row = rows.getJSONObject(i); // Get row object
JSONArray elements = row.getJSONArray("elements"); // Get all elements for each row as an array
for(int j=0; j < elements.length(); j++) { // Iterate each element in the elements array
JSONObject element = elements.getJSONObject(j); // Get the element object
JSONObject duration = element.getJSONObject("duration"); // Get duration sub object
JSONObject distance = element.getJSONObject("distance"); // Get distance sub object
System.out.println("Duration: " + duration.getInt("value")); // Print int value
System.out.println("Distance: " + distance.getInt("value")); // Print int value
}
}
} catch (JSONException e) {
// JSON Parsing error
e.printStackTrace();
}
}
}
Create an class structure that reflects the JSON
Use a library like Jackson or GSON to deserialize the json to instances of your classes.
If you want a more dynamic approach, the above frameworks can also serialize to maps.
Use a library for working with JSON. For example google-gson.
as Bozho said create class structure that reflacts JSON and then use jacson library as follow:
refer Parsing JSON File Java
ObjectMapper mapper = new ObjectMapper();
Projects projs =
mapper.readValue(new File("projects.json"),Projects.class);
ArrayList<Project> projects = projs.get("projects");
for (Project p : projects) {
ArrayList<String> description = p.getDescription();
for (String s : description) {
System.out.println(s);
You can use a library like JSON-java
import org.json.JSONObject;
String jsonString = ...
JSONObject object = new JSONObject(jsonString);
String status = object.getString("status");
You can use :
org.bson.Document d = org.bson.Document.parse("{ foo: \"bar\" }");
yes you can use jacson to parse it but there is more easy way to do it
its Jsonme lib "import org.json.me" you dont have to add jar file to use it
JSONObject obj = new JSONObject("{'var1':'val1','var2':200});
String var1=obj.getString("var1");
int var2=obj.getInt("var2");
yes its more easy but if your project is complex i advice you to use jacson lib

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