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How to parse a JSONString and turn its values into an Array?

How to parse a JSONString, from a once JSONString.stringify simple array that now "appears flattened" inside, and turn its values back into a Java List or Java Array? (Using Jersey 1.x & Java) ? Array originally started as [1,2,3] before it was stringify-ed.
items = (3) [" To", "8357", "30028"] --> JSON.stringify(items) sent through rest call
Chrome Dev Tools's Request Payload after rest call:
items=%5B%22%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0To%22%2C%228357%22%2C%2230028%22%5D
/*inside (Jersey) Rest Resource
#POST
#Path("/...")
#Consumes(MediaType.APPLICATION_JSON)
#Produces(MediaType.APPLICATION_JSON)
public Response receive(#Context SecurityContext securityContext, #Context
HttpServletRequest srequest, String jsonString) throws URISyntaxException,
JSONException ...
/*eclipse watch on jsonString inside (Jersey) Rest Resource
items=%5B%22%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0To%22%2C%228357%22%2C%2230028%22%5D
*/[enter image description here][2]
NOTE: There is no name value. There is no entity.
There's only a very simple string of IDs because that's all I need. (Is that supported by Jersey 1.X or JAX-RS 1.X?)
JSONArray jSONArray = new JSONArray(java.util.Arrays.asList(jsonString));
Eclipse jSONArray Expression: jSONArray
--myArrayList
----elementData
------[0] "items=%5B%22%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0%C2%A0To%22%2C%228357%22%2C%2230028%22%5D"
----------value
------------[0..99]
---------------[0] i
---------------1 t
---------------[2] e
---------------[3] m
---------------[4] s
---------------[5] =
---------------[6] %
---------------[7] 5
---------------[8] B ....

I cannot understand exactly your original question, but one of the way is:
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import javax.swing.JFileChooser;
import org.json.simple.JSONObject;
import org.json.simple.parser.JSONParser;
public class JsonParser {
JFileChooser chooser = new JFileChooser();
File f;
static String fn = "";
static String js1 = "{\"name\": \"LALA\", \"email\": \"tst#tst.com\"}";
String name = "name";
String email = "email";
String fName = "firsName";
String city = "city";
// ... other needed fields
User u1 = null;
public JsonParser() {
parseFile();
System.out.println("\n" + u1.toShortString());
}
private String openFchooser() throws FileNotFoundException, IOException, InterruptedException, Exception {
int returnVal = chooser.showOpenDialog(null);
if (returnVal == JFileChooser.APPROVE_OPTION) {
f = chooser.getSelectedFile();
}
return f.getAbsolutePath();
}
// To parse JSON files with data
//===========================================
public void parseFile() {
JSONParser parser = new JSONParser();
try {
// To parse obj 1
Object obj1 = parser.parse(js1);
System.out.println("User 1: " + obj1.toString());
System.out.println();
JSONObject jobj1 = (JSONObject) obj1;
String from_name = jobj1.get(name).toString();
String from_email = jobj1.get(email).toString();
// String from_fName = jobj1.get(fName).toString();
// String from_city = jobj1.get(city).toString();
u1 = new User(from_name, from_email, null, null);
// System.out.println(u1.toString() + "\n");
} catch (Exception e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
new JsonParser();
}
class User {
String name = null;
String email = null;
String fName = null;
String city = null;
public User(String n, String e, String f, String c) {
this.name = n;
this.email = e;
this.fName = f;
this.city = c;
}
public String getFirsName() {
return this.name;
}
public String setFirsName(String s) {
return this.name = s;
}
public String getEmail() {
return this.email;
}
public String setEmail(String s) {
return this.email = s;
}
public String toString() {
return "{\"name\":" + this.name + ", "
+ "\"email\":" + this.email + ", "
+ "\"firsName\":" + this.fName + ", "
+ "\"city\":" + this.city + "\"}";
}
public String toShortString() {
return "{\"name\": \"" + this.name + "\", "
+ "\"email\": \"" + this.email + "\"}";
}
};
}
OUTPUT:
User 1: {"name":"LALA","email":"tst#tst.com"}
{"name": "LALA", "email": "tst#tst.com"}

Thanks guys. I managed to find an alternative send & receive:
now sending array without stringify-ing it first
receiving with:
public Response archiveSelectedApplicants(#Context SecurityContext securityContext, #Context HttpServletRequest srequest,
#FormParam("items[]") List items) throws URISyntaxException

uniVocity doesn't parse the first column into beans

I'm trying to read CSV files from GTFS.zip with help of uniVocity-parsers and run into an issue that I can't figure out. For some reason it seems the first column of some CSV files won't be parsed correctly. For example in the "stops.txt" file that looks like this:
stop_id,stop_name,stop_lat,stop_lon,location_type,parent_station
"de:3811:30215:0:6","Freiburg Stübeweg","48.0248455941735","7.85563688037231","","Parent30215"
"de:8311:30054:0:1","Freiburg Schutternstraße","48.0236251356332","7.72434519425597","","Parent30054"
"de:8311:30054:0:2","Freiburg Schutternstraße","48.0235446600679","7.72438739944883","","Parent30054"
The "stop_id" field won't be parsed correctly will have the value "null"
This is the method I'm using to read the file:
public <T> List<T> readCSV(String path, String file, BeanListProcessor<T> processor) {
List<T> content = null;
try {
// Get zip file
ZipFile zip = new ZipFile(path);
// Get CSV file
ZipEntry entry = zip.getEntry(file);
InputStream in = zip.getInputStream(entry);
CsvParserSettings parserSettings = new CsvParserSettings();
parserSettings.setProcessor(processor);
parserSettings.setHeaderExtractionEnabled(true);
CsvParser parser = new CsvParser(parserSettings);
parser.parse(new InputStreamReader(in));
content = processor.getBeans();
zip.close();
return content;
} catch (Exception e) {
e.printStackTrace();
}
return content;
}
And this is how my Stop Class looks like:
public class Stop {
#Parsed
private String stop_id;
#Parsed
private String stop_name;
#Parsed
private String stop_lat;
#Parsed
private String stop_lon;
#Parsed
private String location_type;
#Parsed
private String parent_station;
public Stop() {
}
public Stop(String stop_id, String stop_name, String stop_lat, String stop_lon, String location_type,
String parent_station) {
this.stop_id = stop_id;
this.stop_name = stop_name;
this.stop_lat = stop_lat;
this.stop_lon = stop_lon;
this.location_type = location_type;
this.parent_station = parent_station;
}
// --------------------- Getter --------------------------------
public String getStop_id() {
return stop_id;
}
public String getStop_name() {
return stop_name;
}
public String getStop_lat() {
return stop_lat;
}
public String getStop_lon() {
return stop_lon;
}
public String getLocation_type() {
return location_type;
}
public String getParent_station() {
return parent_station;
}
// --------------------- Setter --------------------------------
public void setStop_id(String stop_id) {
this.stop_id = stop_id;
}
public void setStop_name(String stop_name) {
this.stop_name = stop_name;
}
public void setStop_lat(String stop_lat) {
this.stop_lat = stop_lat;
}
public void setStop_lon(String stop_lon) {
this.stop_lon = stop_lon;
}
public void setLocation_type(String location_type) {
this.location_type = location_type;
}
public void setParent_station(String parent_station) {
this.parent_station = parent_station;
}
#Override
public String toString() {
return "Stop [stop_id=" + stop_id + ", stop_name=" + stop_name + ", stop_lat=" + stop_lat + ", stop_lon="
+ stop_lon + ", location_type=" + location_type + ", parent_station=" + parent_station + "]";
}
}
If I call the method i get this output which is not correct:
PartialReading pr = new PartialReading();
List<Stop> stops = pr.readCSV("VAGFR.zip", "stops.txt", new BeanListProcessor<Stop>(Stop.class));
for (int i = 0; i < 4; i++) {
System.out.println(stops.get(i).toString());
}
Output:
Stop [stop_id=null, stop_name=Freiburg Stübeweg, stop_lat=48.0248455941735, stop_lon=7.85563688037231, location_type=null, parent_station=Parent30215]
Stop [stop_id=null, stop_name=Freiburg Schutternstraße, stop_lat=48.0236251356332, stop_lon=7.72434519425597, location_type=null, parent_station=Parent30054]
Stop [stop_id=null, stop_name=Freiburg Schutternstraße, stop_lat=48.0235446600679, stop_lon=7.72438739944883, location_type=null, parent_station=Parent30054]
Stop [stop_id=null, stop_name=Freiburg Waltershofen Ochsen, stop_lat=48.0220902613143, stop_lon=7.7205756507492, location_type=null, parent_station=Parent30055]
Does anyone know why this happens and how I can fix it? This also happens in the "routes.txt" and "trips.txt" files that I tested.
This is the GTFS file : http://stadtplan.freiburg.de/sld/VAGFR.zip

If you print the headers you will notice that the first column doesn't look right. That's because you are parsing a file encoded using UTF-8 with a BOM marker.
Basically the file starts with a few bytes indicating what is the encoding. Until version 2.5.*, the parser didn't handle that internally, and you had to skip these bytes to get the correct output:
//... your code here
ZipEntry entry = zip.getEntry(file);
InputStream in = zip.getInputStream(entry);
if(in.read() == 239 & in.read() == 187 & in.read() == 191){
System.out.println("UTF-8 with BOM, bytes discarded");
}
CsvParserSettings parserSettings = new CsvParserSettings();
//...rest of your code here
The above hack will work on any version before 2.5.*, but you could also use Commons-IO provides a BOMInputStream for convenience and a more clean handling of this sort of thing - it's just VERY slow.
Updating to a recent version should take care of it automatically.
Hope it helps.

Getting additional info using Google's Gson

I have a program that I found on SO that allows the user to input a query and search using Google with whatever is inputted. The program then returns the first 4 results that Google gives. Here is the code:
public class TestGoogleSea {
public static void main(String[] args) throws IOException {
String address = "http://ajax.googleapis.com/ajax/services/search/web?v=1.0&q=";
String query = "who was the 19th president of america";
String charset = "UTF-8";
URL url = new URL(address + URLEncoder.encode(query, charset));
Reader reader = new InputStreamReader(url.openStream(), charset);
GoogleResults results = new Gson().fromJson(reader, GoogleResults.class);
int total = results.getResponseData().getResults().size();
System.out.println("total: "+total);
// Show title and URL of each results
for(int i=0; i<=total-1; i++){
System.out.println("Title: " + results.getResponseData().getResults().get(I).getTitle());
System.out.println("URL: " + results.getResponseData().getResults().get(I).getUrl() + "\n");
}
}
}
class GoogleResults{
private ResponseData responseData;
public ResponseData getResponseData() { return responseData; }
public void setResponseData(ResponseData responseData) { this.responseData = responseData; }
public String toString() { return "ResponseData[" + responseData + "]"; }
static class ResponseData {
private List<Result> results;
public List<Result> getResults() { return results; }
public void setResults(List<Result> results) { this.results = results; }
public String toString() { return "Results[" + results + "]"; }
}
static class Result {
private String url;
private String title;
public String getUrl() { return url; }
public String getTitle() { return title; }
public void setUrl(String url) { this.url = url; }
public void setTitle(String title) { this.title = title; }
public String toString() { return "Result[url:" + url +", title:" + title + "]"; }
}
}
For this specific case, (when the query is "who was the 19th president of america") the output is this:
Total: 4
Title: Rutherford B. Hayes - Wikipedia, the free encyclopedia
URL: http://en.wikipedia.org/wiki/Rutherford_B._Hayes
Title: List of <b>Presidents</b> of the United States - Wikipedia, the free <b>...</b>
URL: http://en.wikipedia.org/wiki/List_of_Presidents_of_the_United_States
Title: Rutherford B. Hayes | The White House
URL: http://www.whitehouse.gov/about/presidents/rutherfordbhayes
Title: <b>American President</b>: Rutherford Birchard Hayes - Miller Center
URL: http://millercenter.org/president/hayes
Now, if you were actually searching "who was the 19th president of america" on Google, in addition of list of the sites, you would see the picture of Rutherford B. Hayes with his name and the option to read "more about Rutherford B. Hayes". What I'm asking is if there is anyway I can get that information, the short little description of Hayes that Google got from Wikipedia most preferably as a string, or if that's not possible due to the limits of Gson?

Google search API return false

I have tool code use Google search API.
My code:
import com.google.gson.Gson;
class GoogleResults {
private ResponseData responseData;
public ResponseData getResponseData() {
return responseData;
}
public void setResponseData(ResponseData responseData) {
this.responseData = responseData;
}
public String toString() {
return "ResponseData[" + responseData + "]";
}
static class ResponseData {
private List<Result> results;
public List<Result> getResults() {
return results;
}
public void setResults(List<Result> results) {
this.results = results;
}
public String toString() {
return "Results[" + results + "]";
}
}
static class Result {
private String url;
public String getUrl() {
return url;
}
public void setUrl(String url) {
this.url = url;
}
public String toString() {
return "Result[url:" + url + " ]";
}
}
}
public class CrawData {
public static void main(String[] args) throws IOException, InterruptedException {
String query;
int n;
int k=0;
String site;
String resultset;
Scanner st = new Scanner(System.in);
System.out.print(" Input key search: ");
query = st.nextLine();
System.out.print("Input site: ");
site = st.nextLine();
System.out.print("Input number of result: ");
n = st.nextInt();
resultset = query + " site:" + site;
for (int j = 0; j < n; j = j + 1) {
Thread.sleep(4000);
String address = "http://ajax.googleapis.com/ajax/services/search/web?v=1.0&start="+j+"&q=";
String charset = "UTF-8";
URL url = new URL(address + URLEncoder.encode(resultset, charset));
Reader reader = new InputStreamReader(url.openStream(), charset);
GoogleResults results = new Gson().fromJson(reader,
GoogleResults.class);
int total = results.getResponseData().getResults().size();
// Show title and URL of each results
for (int i = 0; i <= total - 1; i++) {
String Url = results.getResponseData().getResults().get(i)
.getUrl();
k = k+1;
System.out.println("URL: " +Url+ " " + k);
}
}
}
}
when i run it, i have trouble about result return of code.
My system return list url of website.. but it not stable.
Some picture:
my error
Have error: Exception in thread "main" java.lang.NullPointerException
at CrawData.main(CrawData.java:107)
help me...
Sorry my english is too bad.. :(

My guess is that on this line:
String Url = results.getResponseData().getResults().get(i)
.getUrl();
Either get(i) is returning null or getUrl() is returning null. You should add some error handling logic:
if (results.getResponseData().getResults().get(i) != null &&
results.getResponseData().getResults().get(i).getUrl() !=null) {
String Url = results.getResponseData().getResults().get(i)
.getUrl();
k = k+1;
System.out.println("URL: " +Url+ " " + k);
} else {
// Print some type of error here. Try to figure out why the result or the
// url is null
}

Trouble with a small library-management program

I'm having major trouble piecing this together. I have basic read and write functionality. What I need is for the input from file 'Books.txt' to be checked so that:
ISBN is valid
CopyNumber, Year and Statistics should be numeric
Title, Author and Publisher must contain values
BorrowDate must be a valid date
ReturnDate if available must be a valid date
LibraryCardNumber if available must be numeric.
If a book is not borrowed the two last fields are nonexistent.
2 sample rows from 'Books.txt':
9780140455168#2#The Twelve Caesars#Suetonius#Penguin Classics#2007#3#101009#101030#5478
9780141188607#1#Claudius the God#Robert Graves#Penguin Classics#2006#2#080123
Error lines should be written to 'ErrorLines.txt' with an error-message, e.g. Wrong ISBN. Error-free books should be written to 'NewBooks.txt' sorted by name of author.
Here's what I've got so far. I'm not looking for a complete solution, because I obviously have a looong way to go, but if someone would be so kind as to give me some pointers, I'd be extremely grateful! And yes, it's homework :D
Do I need to make a try loop to validate the input...?
The Library class:
import java.util.ArrayList;
import java.util.*;
import java.io.*;
import java.io.IOException;
public class Library {
public void readFromFile (String filename) throws IOException {
String inLine;
File inFile;
inFile = new File("Books.txt");
BufferedReader fIn = new BufferedReader(new FileReader(inFile));
inLine = fIn.readLine();
while (inLine != null) {
inLine = fIn.readLine();
aBookList.add(inLine + "\n");
}
fIn.close();
}
public void writeToFile (String fileName) throws IOException {
BufferedWriter bw = null;
try {
bw = new BufferedWriter(new FileWriter(fileName));
bw.write("???"); //Dont know what to put here...
bw.newLine();
} catch (IOException e) {
System.out.println("Error writing file.");
} finally {
bw.close();
}
}
public static boolean isISBN13Valid(isbn) {
int check = 0;
for (int i = 0; i < 12; i += 2) {
check += Integer.valueOf(isbn.substring(i, i + 1));
}
for (int i = 1; i < 12; i += 2) {
check += Integer.valueOf(isbn.substring(i, i + 1)) * 3;
}
check += Integer.valueOf(isbn.substring(12));
return check % 10 == 0;
}
}
And here's the Book class:
import java.util.*;
import java.io.*;
public class Book {
Book b = new Book();
private static ArrayList<String> aBookList = new ArrayList<String>();
private String Isbn;
private int CopyNumber;
private String Title;
private String Author;
private String Publisher;
private int Year;
private int Statistics;
private String BorrowDate;
private String ReturnDate;
private int LibraryCardNumber;
public void bookInfo (String nIsbn, int nCopyNumber, String nTitle, String nAuthor, String nPublisher, int nYear,
int nStatistics, String nBorrowDate, String nReturnDate, int nLibraryCardNumber) {
Isbn = nIsbn;
CopyNumber = nCopyNumber;
Title = nTitle;
Author = nAuthor;
Publisher = nPublisher;
Year = nYear;
Statistics = nStatistics;
BorrowDate = nBorrowDate;
ReturnDate = nReturnDate;
LibraryCardNumber = nLibraryCardNumber;
}
public void bookInfo (String Row) {
StringTokenizer sT = new StringTokenizer(Row);
Isbn = sT.nextToken("#");
CopyNumber = Integer.parseInt(sT.nextToken("#") );
Title = sT.nextToken("#");
Author = sT.nextToken("#");
Publisher = sT.nextToken("#");
Year = Integer.parseInt(sT.nextToken("#") );
Statistics = Integer.parseInt(sT.nextToken("#") );
BorrowDate = sT.nextToken("#");
ReturnDate = sT.nextToken("#");
LibraryCardNumber = Integer.parseInt(sT.nextToken("#") );
}
public void setIsbn(String nIsbn) {
Isbn = nIsbn;
}
public void setCopynumber(int nCopyNumber) {
CopyNumber = nCopyNumber;
}
public void setTitle(String nTitle) {
Title = nTitle;
}
public void setAuthor(String nAuthor) {
Author = nAuthor;
}
public void setPublisher(String nPublisher) {
Publisher = nPublisher;
}
public void setYear(int nYear) {
Year = nYear;
}
public void setStatistics(int nStatistics) {
Statistics = nStatistics;
}
public void setBorrowDate(String nBorrowDate) {
BorrowDate = nBorrowDate;
}
public void setReturnDate(String nReturnDate) {
ReturnDate = nReturnDate;
}
public void setLibraryCardNumber(int nLibraryCardNumber) {
LibraryCardNumber = nLibraryCardNumber;
}
public String getAll () {
String s = " ";
return (Isbn + s + CopyNumber + s + Title + s + Author + s + Publisher + s +
Year + s + Statistics + s + BorrowDate + s + ReturnDate + s +
LibraryCardNumber);
}
public void showAll () {
String t = "\t";
System.out.println(Isbn + t + CopyNumber + t + Title + t + Author + t +
Publisher + t + Year + t + Statistics + t +
BorrowDate + t + ReturnDate + t + LibraryCardNumber);
}
}
And finally there's the Main class with main method:
public class Main<aBookList> implements Comparable<aBookList> {
public static void main(String [] args) throws Exception {
new Library().readFromFile("Books.txt");
new Library().writeToFile("NewBooks.txt");
new Library().writeToFile("ErrorLines.txt");
}
#Override
public int compareTo(aBookList o) {
return 0;
}
}

as it is homework, i will point you direction, not give you code
1) you have lot of mess here, ie i'm not sure why you have compare in your main class? instead of creating getAll method in bookInfo(which is named against java nameing convention) just override toString method
2) why do you have list of strings? read a line, convert this into book, if book is valid add it to your list, otherwise report an error
3) move your isISBN13Valid method to book
4) write to file -> loop through your list, and save each element into file by bw.write(book.toString()),
5) create second method createErrorFile, then each error what you will have add into your error list, and after you call that method, you will sace each element into given file, it is not perfetc solution, better will be if you add error to file each time when it occur.
6) create one instance of library in your main method, and just call on it all your method, and avoid using static fields in your project(sometimes you must, but if you don;t need, just avoid them)
7) names for method import/ export i think sounds nicer than read from file read from file